Annotation of elwix/files/sqlite/dist/sqlite3.h, revision 1.4.2.3
1.2 misho 1: /*
1.4.2.2 misho 2: ** 2001-09-15
1.2 misho 3: **
4: ** The author disclaims copyright to this source code. In place of
5: ** a legal notice, here is a blessing:
6: **
7: ** May you do good and not evil.
8: ** May you find forgiveness for yourself and forgive others.
9: ** May you share freely, never taking more than you give.
10: **
11: *************************************************************************
12: ** This header file defines the interface that the SQLite library
13: ** presents to client programs. If a C-function, structure, datatype,
14: ** or constant definition does not appear in this file, then it is
15: ** not a published API of SQLite, is subject to change without
16: ** notice, and should not be referenced by programs that use SQLite.
17: **
18: ** Some of the definitions that are in this file are marked as
19: ** "experimental". Experimental interfaces are normally new
20: ** features recently added to SQLite. We do not anticipate changes
21: ** to experimental interfaces but reserve the right to make minor changes
22: ** if experience from use "in the wild" suggest such changes are prudent.
23: **
24: ** The official C-language API documentation for SQLite is derived
25: ** from comments in this file. This file is the authoritative source
1.4 misho 26: ** on how SQLite interfaces are supposed to operate.
1.2 misho 27: **
28: ** The name of this file under configuration management is "sqlite.h.in".
29: ** The makefile makes some minor changes to this file (such as inserting
30: ** the version number) and changes its name to "sqlite3.h" as
31: ** part of the build process.
32: */
1.4 misho 33: #ifndef SQLITE3_H
34: #define SQLITE3_H
1.2 misho 35: #include <stdarg.h> /* Needed for the definition of va_list */
36:
37: /*
38: ** Make sure we can call this stuff from C++.
39: */
40: #ifdef __cplusplus
41: extern "C" {
42: #endif
43:
44:
45: /*
1.4 misho 46: ** Provide the ability to override linkage features of the interface.
1.2 misho 47: */
48: #ifndef SQLITE_EXTERN
49: # define SQLITE_EXTERN extern
50: #endif
51: #ifndef SQLITE_API
52: # define SQLITE_API
53: #endif
1.4 misho 54: #ifndef SQLITE_CDECL
55: # define SQLITE_CDECL
56: #endif
57: #ifndef SQLITE_APICALL
58: # define SQLITE_APICALL
59: #endif
60: #ifndef SQLITE_STDCALL
61: # define SQLITE_STDCALL SQLITE_APICALL
62: #endif
63: #ifndef SQLITE_CALLBACK
64: # define SQLITE_CALLBACK
65: #endif
66: #ifndef SQLITE_SYSAPI
67: # define SQLITE_SYSAPI
68: #endif
1.2 misho 69:
70: /*
71: ** These no-op macros are used in front of interfaces to mark those
72: ** interfaces as either deprecated or experimental. New applications
1.4 misho 73: ** should not use deprecated interfaces - they are supported for backwards
1.2 misho 74: ** compatibility only. Application writers should be aware that
75: ** experimental interfaces are subject to change in point releases.
76: **
77: ** These macros used to resolve to various kinds of compiler magic that
78: ** would generate warning messages when they were used. But that
79: ** compiler magic ended up generating such a flurry of bug reports
80: ** that we have taken it all out and gone back to using simple
81: ** noop macros.
82: */
83: #define SQLITE_DEPRECATED
84: #define SQLITE_EXPERIMENTAL
85:
86: /*
87: ** Ensure these symbols were not defined by some previous header file.
88: */
89: #ifdef SQLITE_VERSION
90: # undef SQLITE_VERSION
91: #endif
92: #ifdef SQLITE_VERSION_NUMBER
93: # undef SQLITE_VERSION_NUMBER
94: #endif
95:
96: /*
97: ** CAPI3REF: Compile-Time Library Version Numbers
98: **
99: ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
100: ** evaluates to a string literal that is the SQLite version in the
101: ** format "X.Y.Z" where X is the major version number (always 3 for
102: ** SQLite3) and Y is the minor version number and Z is the release number.)^
103: ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
104: ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
105: ** numbers used in [SQLITE_VERSION].)^
106: ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
107: ** be larger than the release from which it is derived. Either Y will
108: ** be held constant and Z will be incremented or else Y will be incremented
109: ** and Z will be reset to zero.
110: **
1.4.2.3 ! misho 111: ** Since [version 3.6.18] ([dateof:3.6.18]),
1.4.2.1 misho 112: ** SQLite source code has been stored in the
1.2 misho 113: ** <a href="http://www.fossil-scm.org/">Fossil configuration management
114: ** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to
115: ** a string which identifies a particular check-in of SQLite
116: ** within its configuration management system. ^The SQLITE_SOURCE_ID
1.4.2.1 misho 117: ** string contains the date and time of the check-in (UTC) and a SHA1
1.4.2.2 misho 118: ** or SHA3-256 hash of the entire source tree. If the source code has
119: ** been edited in any way since it was last checked in, then the last
120: ** four hexadecimal digits of the hash may be modified.
1.2 misho 121: **
122: ** See also: [sqlite3_libversion()],
123: ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
124: ** [sqlite_version()] and [sqlite_source_id()].
125: */
1.4.2.3 ! misho 126: #define SQLITE_VERSION "3.33.0"
! 127: #define SQLITE_VERSION_NUMBER 3033000
! 128: #define SQLITE_SOURCE_ID "2020-08-14 13:23:32 fca8dc8b578f215a969cd899336378966156154710873e68b3d9ac5881b0ff3f"
1.2 misho 129:
130: /*
131: ** CAPI3REF: Run-Time Library Version Numbers
1.4.2.1 misho 132: ** KEYWORDS: sqlite3_version sqlite3_sourceid
1.2 misho 133: **
134: ** These interfaces provide the same information as the [SQLITE_VERSION],
135: ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
136: ** but are associated with the library instead of the header file. ^(Cautious
137: ** programmers might include assert() statements in their application to
138: ** verify that values returned by these interfaces match the macros in
1.4 misho 139: ** the header, and thus ensure that the application is
1.2 misho 140: ** compiled with matching library and header files.
141: **
142: ** <blockquote><pre>
143: ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
1.4.2.2 misho 144: ** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
1.2 misho 145: ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
146: ** </pre></blockquote>)^
147: **
148: ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
149: ** macro. ^The sqlite3_libversion() function returns a pointer to the
150: ** to the sqlite3_version[] string constant. The sqlite3_libversion()
151: ** function is provided for use in DLLs since DLL users usually do not have
152: ** direct access to string constants within the DLL. ^The
153: ** sqlite3_libversion_number() function returns an integer equal to
1.4.2.3 ! misho 154: ** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns
! 155: ** a pointer to a string constant whose value is the same as the
1.4.2.2 misho 156: ** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built
157: ** using an edited copy of [the amalgamation], then the last four characters
158: ** of the hash might be different from [SQLITE_SOURCE_ID].)^
1.2 misho 159: **
160: ** See also: [sqlite_version()] and [sqlite_source_id()].
161: */
162: SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
163: SQLITE_API const char *sqlite3_libversion(void);
164: SQLITE_API const char *sqlite3_sourceid(void);
165: SQLITE_API int sqlite3_libversion_number(void);
166:
167: /*
168: ** CAPI3REF: Run-Time Library Compilation Options Diagnostics
169: **
1.4.2.3 ! misho 170: ** ^The sqlite3_compileoption_used() function returns 0 or 1
! 171: ** indicating whether the specified option was defined at
! 172: ** compile time. ^The SQLITE_ prefix may be omitted from the
! 173: ** option name passed to sqlite3_compileoption_used().
1.2 misho 174: **
175: ** ^The sqlite3_compileoption_get() function allows iterating
176: ** over the list of options that were defined at compile time by
177: ** returning the N-th compile time option string. ^If N is out of range,
1.4.2.3 ! misho 178: ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
! 179: ** prefix is omitted from any strings returned by
1.2 misho 180: ** sqlite3_compileoption_get().
181: **
182: ** ^Support for the diagnostic functions sqlite3_compileoption_used()
1.4.2.3 ! misho 183: ** and sqlite3_compileoption_get() may be omitted by specifying the
1.2 misho 184: ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
185: **
186: ** See also: SQL functions [sqlite_compileoption_used()] and
187: ** [sqlite_compileoption_get()] and the [compile_options pragma].
188: */
189: #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
190: SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
191: SQLITE_API const char *sqlite3_compileoption_get(int N);
1.4.2.2 misho 192: #else
193: # define sqlite3_compileoption_used(X) 0
194: # define sqlite3_compileoption_get(X) ((void*)0)
1.2 misho 195: #endif
196:
197: /*
198: ** CAPI3REF: Test To See If The Library Is Threadsafe
199: **
200: ** ^The sqlite3_threadsafe() function returns zero if and only if
201: ** SQLite was compiled with mutexing code omitted due to the
202: ** [SQLITE_THREADSAFE] compile-time option being set to 0.
203: **
204: ** SQLite can be compiled with or without mutexes. When
205: ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
206: ** are enabled and SQLite is threadsafe. When the
1.4.2.3 ! misho 207: ** [SQLITE_THREADSAFE] macro is 0,
1.2 misho 208: ** the mutexes are omitted. Without the mutexes, it is not safe
209: ** to use SQLite concurrently from more than one thread.
210: **
211: ** Enabling mutexes incurs a measurable performance penalty.
212: ** So if speed is of utmost importance, it makes sense to disable
213: ** the mutexes. But for maximum safety, mutexes should be enabled.
214: ** ^The default behavior is for mutexes to be enabled.
215: **
216: ** This interface can be used by an application to make sure that the
217: ** version of SQLite that it is linking against was compiled with
218: ** the desired setting of the [SQLITE_THREADSAFE] macro.
219: **
220: ** This interface only reports on the compile-time mutex setting
221: ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
222: ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
223: ** can be fully or partially disabled using a call to [sqlite3_config()]
224: ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
1.4 misho 225: ** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the
1.2 misho 226: ** sqlite3_threadsafe() function shows only the compile-time setting of
227: ** thread safety, not any run-time changes to that setting made by
228: ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
229: ** is unchanged by calls to sqlite3_config().)^
230: **
231: ** See the [threading mode] documentation for additional information.
232: */
233: SQLITE_API int sqlite3_threadsafe(void);
234:
235: /*
236: ** CAPI3REF: Database Connection Handle
237: ** KEYWORDS: {database connection} {database connections}
238: **
239: ** Each open SQLite database is represented by a pointer to an instance of
240: ** the opaque structure named "sqlite3". It is useful to think of an sqlite3
241: ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
242: ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
1.3 misho 243: ** and [sqlite3_close_v2()] are its destructors. There are many other
244: ** interfaces (such as
1.2 misho 245: ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
246: ** [sqlite3_busy_timeout()] to name but three) that are methods on an
247: ** sqlite3 object.
248: */
249: typedef struct sqlite3 sqlite3;
250:
251: /*
252: ** CAPI3REF: 64-Bit Integer Types
253: ** KEYWORDS: sqlite_int64 sqlite_uint64
254: **
255: ** Because there is no cross-platform way to specify 64-bit integer types
256: ** SQLite includes typedefs for 64-bit signed and unsigned integers.
257: **
258: ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
259: ** The sqlite_int64 and sqlite_uint64 types are supported for backwards
260: ** compatibility only.
261: **
262: ** ^The sqlite3_int64 and sqlite_int64 types can store integer values
263: ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
1.4.2.3 ! misho 264: ** sqlite3_uint64 and sqlite_uint64 types can store integer values
1.2 misho 265: ** between 0 and +18446744073709551615 inclusive.
266: */
267: #ifdef SQLITE_INT64_TYPE
268: typedef SQLITE_INT64_TYPE sqlite_int64;
1.4.2.1 misho 269: # ifdef SQLITE_UINT64_TYPE
270: typedef SQLITE_UINT64_TYPE sqlite_uint64;
1.4.2.3 ! misho 271: # else
1.4.2.1 misho 272: typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
273: # endif
1.2 misho 274: #elif defined(_MSC_VER) || defined(__BORLANDC__)
275: typedef __int64 sqlite_int64;
276: typedef unsigned __int64 sqlite_uint64;
277: #else
278: typedef long long int sqlite_int64;
279: typedef unsigned long long int sqlite_uint64;
280: #endif
281: typedef sqlite_int64 sqlite3_int64;
282: typedef sqlite_uint64 sqlite3_uint64;
283:
284: /*
285: ** If compiling for a processor that lacks floating point support,
286: ** substitute integer for floating-point.
287: */
288: #ifdef SQLITE_OMIT_FLOATING_POINT
289: # define double sqlite3_int64
290: #endif
291:
292: /*
293: ** CAPI3REF: Closing A Database Connection
1.4 misho 294: ** DESTRUCTOR: sqlite3
1.2 misho 295: **
1.3 misho 296: ** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
297: ** for the [sqlite3] object.
1.4 misho 298: ** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
1.3 misho 299: ** the [sqlite3] object is successfully destroyed and all associated
300: ** resources are deallocated.
301: **
1.4.2.3 ! misho 302: ** Ideally, applications should [sqlite3_finalize | finalize] all
! 303: ** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and
1.3 misho 304: ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
1.4.2.3 ! misho 305: ** with the [sqlite3] object prior to attempting to close the object.
! 306: ** ^If the database connection is associated with unfinalized prepared
! 307: ** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then
! 308: ** sqlite3_close() will leave the database connection open and return
! 309: ** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared
! 310: ** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups,
! 311: ** it returns [SQLITE_OK] regardless, but instead of deallocating the database
! 312: ** connection immediately, it marks the database connection as an unusable
! 313: ** "zombie" and makes arrangements to automatically deallocate the database
! 314: ** connection after all prepared statements are finalized, all BLOB handles
! 315: ** are closed, and all backups have finished. The sqlite3_close_v2() interface
! 316: ** is intended for use with host languages that are garbage collected, and
! 317: ** where the order in which destructors are called is arbitrary.
1.2 misho 318: **
1.3 misho 319: ** ^If an [sqlite3] object is destroyed while a transaction is open,
1.2 misho 320: ** the transaction is automatically rolled back.
321: **
1.3 misho 322: ** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
323: ** must be either a NULL
1.2 misho 324: ** pointer or an [sqlite3] object pointer obtained
325: ** from [sqlite3_open()], [sqlite3_open16()], or
326: ** [sqlite3_open_v2()], and not previously closed.
1.3 misho 327: ** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
328: ** argument is a harmless no-op.
1.2 misho 329: */
1.3 misho 330: SQLITE_API int sqlite3_close(sqlite3*);
331: SQLITE_API int sqlite3_close_v2(sqlite3*);
1.2 misho 332:
333: /*
334: ** The type for a callback function.
335: ** This is legacy and deprecated. It is included for historical
336: ** compatibility and is not documented.
337: */
338: typedef int (*sqlite3_callback)(void*,int,char**, char**);
339:
340: /*
341: ** CAPI3REF: One-Step Query Execution Interface
1.4 misho 342: ** METHOD: sqlite3
1.2 misho 343: **
344: ** The sqlite3_exec() interface is a convenience wrapper around
345: ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
346: ** that allows an application to run multiple statements of SQL
1.4.2.3 ! misho 347: ** without having to use a lot of C code.
1.2 misho 348: **
349: ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
350: ** semicolon-separate SQL statements passed into its 2nd argument,
351: ** in the context of the [database connection] passed in as its 1st
352: ** argument. ^If the callback function of the 3rd argument to
353: ** sqlite3_exec() is not NULL, then it is invoked for each result row
354: ** coming out of the evaluated SQL statements. ^The 4th argument to
355: ** sqlite3_exec() is relayed through to the 1st argument of each
356: ** callback invocation. ^If the callback pointer to sqlite3_exec()
357: ** is NULL, then no callback is ever invoked and result rows are
358: ** ignored.
359: **
360: ** ^If an error occurs while evaluating the SQL statements passed into
361: ** sqlite3_exec(), then execution of the current statement stops and
362: ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
363: ** is not NULL then any error message is written into memory obtained
364: ** from [sqlite3_malloc()] and passed back through the 5th parameter.
365: ** To avoid memory leaks, the application should invoke [sqlite3_free()]
366: ** on error message strings returned through the 5th parameter of
1.4 misho 367: ** sqlite3_exec() after the error message string is no longer needed.
1.2 misho 368: ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
369: ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
370: ** NULL before returning.
371: **
372: ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
373: ** routine returns SQLITE_ABORT without invoking the callback again and
374: ** without running any subsequent SQL statements.
375: **
376: ** ^The 2nd argument to the sqlite3_exec() callback function is the
377: ** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
378: ** callback is an array of pointers to strings obtained as if from
379: ** [sqlite3_column_text()], one for each column. ^If an element of a
380: ** result row is NULL then the corresponding string pointer for the
381: ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
382: ** sqlite3_exec() callback is an array of pointers to strings where each
383: ** entry represents the name of corresponding result column as obtained
384: ** from [sqlite3_column_name()].
385: **
386: ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
1.4.2.3 ! misho 387: ** to an empty string, or a pointer that contains only whitespace and/or
1.2 misho 388: ** SQL comments, then no SQL statements are evaluated and the database
389: ** is not changed.
390: **
391: ** Restrictions:
392: **
393: ** <ul>
1.4 misho 394: ** <li> The application must ensure that the 1st parameter to sqlite3_exec()
1.2 misho 395: ** is a valid and open [database connection].
1.4 misho 396: ** <li> The application must not close the [database connection] specified by
1.2 misho 397: ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
398: ** <li> The application must not modify the SQL statement text passed into
399: ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
400: ** </ul>
401: */
402: SQLITE_API int sqlite3_exec(
403: sqlite3*, /* An open database */
404: const char *sql, /* SQL to be evaluated */
405: int (*callback)(void*,int,char**,char**), /* Callback function */
406: void *, /* 1st argument to callback */
407: char **errmsg /* Error msg written here */
408: );
409:
410: /*
411: ** CAPI3REF: Result Codes
1.4 misho 412: ** KEYWORDS: {result code definitions}
1.2 misho 413: **
414: ** Many SQLite functions return an integer result code from the set shown
415: ** here in order to indicate success or failure.
416: **
417: ** New error codes may be added in future versions of SQLite.
418: **
1.4 misho 419: ** See also: [extended result code definitions]
1.2 misho 420: */
421: #define SQLITE_OK 0 /* Successful result */
422: /* beginning-of-error-codes */
1.4.2.2 misho 423: #define SQLITE_ERROR 1 /* Generic error */
1.2 misho 424: #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
425: #define SQLITE_PERM 3 /* Access permission denied */
426: #define SQLITE_ABORT 4 /* Callback routine requested an abort */
427: #define SQLITE_BUSY 5 /* The database file is locked */
428: #define SQLITE_LOCKED 6 /* A table in the database is locked */
429: #define SQLITE_NOMEM 7 /* A malloc() failed */
430: #define SQLITE_READONLY 8 /* Attempt to write a readonly database */
431: #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
432: #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
433: #define SQLITE_CORRUPT 11 /* The database disk image is malformed */
434: #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */
435: #define SQLITE_FULL 13 /* Insertion failed because database is full */
436: #define SQLITE_CANTOPEN 14 /* Unable to open the database file */
437: #define SQLITE_PROTOCOL 15 /* Database lock protocol error */
1.4.2.2 misho 438: #define SQLITE_EMPTY 16 /* Internal use only */
1.2 misho 439: #define SQLITE_SCHEMA 17 /* The database schema changed */
440: #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
441: #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
442: #define SQLITE_MISMATCH 20 /* Data type mismatch */
443: #define SQLITE_MISUSE 21 /* Library used incorrectly */
444: #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
445: #define SQLITE_AUTH 23 /* Authorization denied */
1.4.2.2 misho 446: #define SQLITE_FORMAT 24 /* Not used */
1.2 misho 447: #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
448: #define SQLITE_NOTADB 26 /* File opened that is not a database file */
1.4 misho 449: #define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */
450: #define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */
1.2 misho 451: #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
452: #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
453: /* end-of-error-codes */
454:
455: /*
456: ** CAPI3REF: Extended Result Codes
1.4 misho 457: ** KEYWORDS: {extended result code definitions}
1.2 misho 458: **
1.4 misho 459: ** In its default configuration, SQLite API routines return one of 30 integer
460: ** [result codes]. However, experience has shown that many of
1.2 misho 461: ** these result codes are too coarse-grained. They do not provide as
462: ** much information about problems as programmers might like. In an effort to
1.4.2.1 misho 463: ** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
464: ** and later) include
1.2 misho 465: ** support for additional result codes that provide more detailed information
1.4 misho 466: ** about errors. These [extended result codes] are enabled or disabled
1.2 misho 467: ** on a per database connection basis using the
1.4 misho 468: ** [sqlite3_extended_result_codes()] API. Or, the extended code for
469: ** the most recent error can be obtained using
470: ** [sqlite3_extended_errcode()].
1.2 misho 471: */
1.4.2.2 misho 472: #define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8))
473: #define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8))
474: #define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8))
1.2 misho 475: #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
476: #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
477: #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
478: #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
479: #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
480: #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
481: #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
482: #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
483: #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
484: #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
485: #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
486: #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
487: #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
488: #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
489: #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
490: #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
491: #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
492: #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
493: #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
494: #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
495: #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))
496: #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))
1.3 misho 497: #define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8))
1.4 misho 498: #define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8))
499: #define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8))
500: #define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8))
501: #define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8))
502: #define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8))
1.4.2.2 misho 503: #define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8))
504: #define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8))
505: #define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8))
1.4.2.3 ! misho 506: #define SQLITE_IOERR_DATA (SQLITE_IOERR | (32<<8))
1.2 misho 507: #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
1.4.2.2 misho 508: #define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8))
1.2 misho 509: #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
1.4 misho 510: #define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8))
1.4.2.3 ! misho 511: #define SQLITE_BUSY_TIMEOUT (SQLITE_BUSY | (3<<8))
1.2 misho 512: #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
1.3 misho 513: #define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8))
514: #define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8))
1.4 misho 515: #define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8))
1.4.2.2 misho 516: #define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */
1.4.2.3 ! misho 517: #define SQLITE_CANTOPEN_SYMLINK (SQLITE_CANTOPEN | (6<<8))
1.2 misho 518: #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))
1.4.2.2 misho 519: #define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8))
1.4.2.3 ! misho 520: #define SQLITE_CORRUPT_INDEX (SQLITE_CORRUPT | (3<<8))
1.2 misho 521: #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))
522: #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))
1.4 misho 523: #define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8))
524: #define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8))
1.4.2.2 misho 525: #define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8))
526: #define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8))
1.3 misho 527: #define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8))
1.4 misho 528: #define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8))
529: #define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8))
530: #define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8))
531: #define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8))
532: #define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8))
533: #define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8))
534: #define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8))
535: #define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8))
536: #define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8))
537: #define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8))
1.4.2.3 ! misho 538: #define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<8))
1.4 misho 539: #define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8))
540: #define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
541: #define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8))
542: #define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8))
543: #define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8))
1.4.2.3 ! misho 544: #define SQLITE_OK_SYMLINK (SQLITE_OK | (2<<8))
1.2 misho 545:
546: /*
547: ** CAPI3REF: Flags For File Open Operations
548: **
549: ** These bit values are intended for use in the
550: ** 3rd parameter to the [sqlite3_open_v2()] interface and
551: ** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
552: */
553: #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
554: #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
555: #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
556: #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
557: #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
558: #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
559: #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */
1.3 misho 560: #define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */
1.2 misho 561: #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
562: #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
563: #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
564: #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
565: #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
566: #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
1.4.2.3 ! misho 567: #define SQLITE_OPEN_SUPER_JOURNAL 0x00004000 /* VFS only */
1.2 misho 568: #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
569: #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
570: #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
571: #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
572: #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
1.4.2.3 ! misho 573: #define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */
1.2 misho 574:
575: /* Reserved: 0x00F00000 */
1.4.2.3 ! misho 576: /* Legacy compatibility: */
! 577: #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
! 578:
1.2 misho 579:
580: /*
581: ** CAPI3REF: Device Characteristics
582: **
583: ** The xDeviceCharacteristics method of the [sqlite3_io_methods]
1.3 misho 584: ** object returns an integer which is a vector of these
1.2 misho 585: ** bit values expressing I/O characteristics of the mass storage
586: ** device that holds the file that the [sqlite3_io_methods]
587: ** refers to.
588: **
589: ** The SQLITE_IOCAP_ATOMIC property means that all writes of
590: ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
591: ** mean that writes of blocks that are nnn bytes in size and
592: ** are aligned to an address which is an integer multiple of
593: ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
594: ** that when data is appended to a file, the data is appended
595: ** first then the size of the file is extended, never the other
596: ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
597: ** information is written to disk in the same order as calls
598: ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
599: ** after reboot following a crash or power loss, the only bytes in a
600: ** file that were written at the application level might have changed
601: ** and that adjacent bytes, even bytes within the same sector are
1.4 misho 602: ** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
1.4.2.1 misho 603: ** flag indicates that a file cannot be deleted when open. The
1.4 misho 604: ** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
605: ** read-only media and cannot be changed even by processes with
606: ** elevated privileges.
1.4.2.2 misho 607: **
608: ** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying
609: ** filesystem supports doing multiple write operations atomically when those
610: ** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and
611: ** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].
1.2 misho 612: */
613: #define SQLITE_IOCAP_ATOMIC 0x00000001
614: #define SQLITE_IOCAP_ATOMIC512 0x00000002
615: #define SQLITE_IOCAP_ATOMIC1K 0x00000004
616: #define SQLITE_IOCAP_ATOMIC2K 0x00000008
617: #define SQLITE_IOCAP_ATOMIC4K 0x00000010
618: #define SQLITE_IOCAP_ATOMIC8K 0x00000020
619: #define SQLITE_IOCAP_ATOMIC16K 0x00000040
620: #define SQLITE_IOCAP_ATOMIC32K 0x00000080
621: #define SQLITE_IOCAP_ATOMIC64K 0x00000100
622: #define SQLITE_IOCAP_SAFE_APPEND 0x00000200
623: #define SQLITE_IOCAP_SEQUENTIAL 0x00000400
624: #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
625: #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000
1.4 misho 626: #define SQLITE_IOCAP_IMMUTABLE 0x00002000
1.4.2.2 misho 627: #define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000
1.2 misho 628:
629: /*
630: ** CAPI3REF: File Locking Levels
631: **
632: ** SQLite uses one of these integer values as the second
633: ** argument to calls it makes to the xLock() and xUnlock() methods
634: ** of an [sqlite3_io_methods] object.
635: */
636: #define SQLITE_LOCK_NONE 0
637: #define SQLITE_LOCK_SHARED 1
638: #define SQLITE_LOCK_RESERVED 2
639: #define SQLITE_LOCK_PENDING 3
640: #define SQLITE_LOCK_EXCLUSIVE 4
641:
642: /*
643: ** CAPI3REF: Synchronization Type Flags
644: **
645: ** When SQLite invokes the xSync() method of an
646: ** [sqlite3_io_methods] object it uses a combination of
647: ** these integer values as the second argument.
648: **
649: ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
650: ** sync operation only needs to flush data to mass storage. Inode
651: ** information need not be flushed. If the lower four bits of the flag
652: ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
653: ** If the lower four bits equal SQLITE_SYNC_FULL, that means
654: ** to use Mac OS X style fullsync instead of fsync().
655: **
656: ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
657: ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
658: ** settings. The [synchronous pragma] determines when calls to the
659: ** xSync VFS method occur and applies uniformly across all platforms.
660: ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
661: ** energetic or rigorous or forceful the sync operations are and
662: ** only make a difference on Mac OSX for the default SQLite code.
663: ** (Third-party VFS implementations might also make the distinction
664: ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
665: ** operating systems natively supported by SQLite, only Mac OSX
666: ** cares about the difference.)
667: */
668: #define SQLITE_SYNC_NORMAL 0x00002
669: #define SQLITE_SYNC_FULL 0x00003
670: #define SQLITE_SYNC_DATAONLY 0x00010
671:
672: /*
673: ** CAPI3REF: OS Interface Open File Handle
674: **
1.4.2.3 ! misho 675: ** An [sqlite3_file] object represents an open file in the
1.2 misho 676: ** [sqlite3_vfs | OS interface layer]. Individual OS interface
677: ** implementations will
678: ** want to subclass this object by appending additional fields
679: ** for their own use. The pMethods entry is a pointer to an
680: ** [sqlite3_io_methods] object that defines methods for performing
681: ** I/O operations on the open file.
682: */
683: typedef struct sqlite3_file sqlite3_file;
684: struct sqlite3_file {
685: const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
686: };
687:
688: /*
689: ** CAPI3REF: OS Interface File Virtual Methods Object
690: **
691: ** Every file opened by the [sqlite3_vfs.xOpen] method populates an
692: ** [sqlite3_file] object (or, more commonly, a subclass of the
693: ** [sqlite3_file] object) with a pointer to an instance of this object.
694: ** This object defines the methods used to perform various operations
695: ** against the open file represented by the [sqlite3_file] object.
696: **
1.4.2.3 ! misho 697: ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
1.2 misho 698: ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
699: ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The
700: ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
701: ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
702: ** to NULL.
703: **
704: ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
705: ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
706: ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
707: ** flag may be ORed in to indicate that only the data of the file
708: ** and not its inode needs to be synced.
709: **
710: ** The integer values to xLock() and xUnlock() are one of
711: ** <ul>
712: ** <li> [SQLITE_LOCK_NONE],
713: ** <li> [SQLITE_LOCK_SHARED],
714: ** <li> [SQLITE_LOCK_RESERVED],
715: ** <li> [SQLITE_LOCK_PENDING], or
716: ** <li> [SQLITE_LOCK_EXCLUSIVE].
717: ** </ul>
718: ** xLock() increases the lock. xUnlock() decreases the lock.
719: ** The xCheckReservedLock() method checks whether any database connection,
720: ** either in this process or in some other process, is holding a RESERVED,
721: ** PENDING, or EXCLUSIVE lock on the file. It returns true
722: ** if such a lock exists and false otherwise.
723: **
724: ** The xFileControl() method is a generic interface that allows custom
725: ** VFS implementations to directly control an open file using the
726: ** [sqlite3_file_control()] interface. The second "op" argument is an
727: ** integer opcode. The third argument is a generic pointer intended to
728: ** point to a structure that may contain arguments or space in which to
729: ** write return values. Potential uses for xFileControl() might be
730: ** functions to enable blocking locks with timeouts, to change the
731: ** locking strategy (for example to use dot-file locks), to inquire
732: ** about the status of a lock, or to break stale locks. The SQLite
733: ** core reserves all opcodes less than 100 for its own use.
1.4 misho 734: ** A [file control opcodes | list of opcodes] less than 100 is available.
1.2 misho 735: ** Applications that define a custom xFileControl method should use opcodes
736: ** greater than 100 to avoid conflicts. VFS implementations should
737: ** return [SQLITE_NOTFOUND] for file control opcodes that they do not
738: ** recognize.
739: **
740: ** The xSectorSize() method returns the sector size of the
741: ** device that underlies the file. The sector size is the
742: ** minimum write that can be performed without disturbing
743: ** other bytes in the file. The xDeviceCharacteristics()
744: ** method returns a bit vector describing behaviors of the
745: ** underlying device:
746: **
747: ** <ul>
748: ** <li> [SQLITE_IOCAP_ATOMIC]
749: ** <li> [SQLITE_IOCAP_ATOMIC512]
750: ** <li> [SQLITE_IOCAP_ATOMIC1K]
751: ** <li> [SQLITE_IOCAP_ATOMIC2K]
752: ** <li> [SQLITE_IOCAP_ATOMIC4K]
753: ** <li> [SQLITE_IOCAP_ATOMIC8K]
754: ** <li> [SQLITE_IOCAP_ATOMIC16K]
755: ** <li> [SQLITE_IOCAP_ATOMIC32K]
756: ** <li> [SQLITE_IOCAP_ATOMIC64K]
757: ** <li> [SQLITE_IOCAP_SAFE_APPEND]
758: ** <li> [SQLITE_IOCAP_SEQUENTIAL]
1.4.2.1 misho 759: ** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN]
760: ** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE]
761: ** <li> [SQLITE_IOCAP_IMMUTABLE]
1.4.2.2 misho 762: ** <li> [SQLITE_IOCAP_BATCH_ATOMIC]
1.2 misho 763: ** </ul>
764: **
765: ** The SQLITE_IOCAP_ATOMIC property means that all writes of
766: ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
767: ** mean that writes of blocks that are nnn bytes in size and
768: ** are aligned to an address which is an integer multiple of
769: ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
770: ** that when data is appended to a file, the data is appended
771: ** first then the size of the file is extended, never the other
772: ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
773: ** information is written to disk in the same order as calls
774: ** to xWrite().
775: **
776: ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
777: ** in the unread portions of the buffer with zeros. A VFS that
778: ** fails to zero-fill short reads might seem to work. However,
779: ** failure to zero-fill short reads will eventually lead to
780: ** database corruption.
781: */
782: typedef struct sqlite3_io_methods sqlite3_io_methods;
783: struct sqlite3_io_methods {
784: int iVersion;
785: int (*xClose)(sqlite3_file*);
786: int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
787: int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
788: int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
789: int (*xSync)(sqlite3_file*, int flags);
790: int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
791: int (*xLock)(sqlite3_file*, int);
792: int (*xUnlock)(sqlite3_file*, int);
793: int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
794: int (*xFileControl)(sqlite3_file*, int op, void *pArg);
795: int (*xSectorSize)(sqlite3_file*);
796: int (*xDeviceCharacteristics)(sqlite3_file*);
797: /* Methods above are valid for version 1 */
798: int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
799: int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
800: void (*xShmBarrier)(sqlite3_file*);
801: int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
802: /* Methods above are valid for version 2 */
1.4 misho 803: int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
804: int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
805: /* Methods above are valid for version 3 */
1.2 misho 806: /* Additional methods may be added in future releases */
807: };
808:
809: /*
810: ** CAPI3REF: Standard File Control Opcodes
1.4 misho 811: ** KEYWORDS: {file control opcodes} {file control opcode}
1.2 misho 812: **
813: ** These integer constants are opcodes for the xFileControl method
814: ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
815: ** interface.
816: **
1.4 misho 817: ** <ul>
818: ** <li>[[SQLITE_FCNTL_LOCKSTATE]]
1.2 misho 819: ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
820: ** opcode causes the xFileControl method to write the current state of
821: ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
822: ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
823: ** into an integer that the pArg argument points to. This capability
1.4 misho 824: ** is used during testing and is only available when the SQLITE_TEST
825: ** compile-time option is used.
826: **
1.3 misho 827: ** <li>[[SQLITE_FCNTL_SIZE_HINT]]
1.2 misho 828: ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
829: ** layer a hint of how large the database file will grow to be during the
830: ** current transaction. This hint is not guaranteed to be accurate but it
831: ** is often close. The underlying VFS might choose to preallocate database
832: ** file space based on this hint in order to help writes to the database
833: ** file run faster.
834: **
1.4.2.2 misho 835: ** <li>[[SQLITE_FCNTL_SIZE_LIMIT]]
836: ** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that
837: ** implements [sqlite3_deserialize()] to set an upper bound on the size
838: ** of the in-memory database. The argument is a pointer to a [sqlite3_int64].
839: ** If the integer pointed to is negative, then it is filled in with the
840: ** current limit. Otherwise the limit is set to the larger of the value
841: ** of the integer pointed to and the current database size. The integer
842: ** pointed to is set to the new limit.
843: **
1.3 misho 844: ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
1.2 misho 845: ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
846: ** extends and truncates the database file in chunks of a size specified
1.4.2.3 ! misho 847: ** by the user. The fourth argument to [sqlite3_file_control()] should
1.2 misho 848: ** point to an integer (type int) containing the new chunk-size to use
849: ** for the nominated database. Allocating database file space in large
850: ** chunks (say 1MB at a time), may reduce file-system fragmentation and
851: ** improve performance on some systems.
852: **
1.3 misho 853: ** <li>[[SQLITE_FCNTL_FILE_POINTER]]
1.2 misho 854: ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
855: ** to the [sqlite3_file] object associated with a particular database
1.4 misho 856: ** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER].
857: **
858: ** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
859: ** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
860: ** to the [sqlite3_file] object associated with the journal file (either
861: ** the [rollback journal] or the [write-ahead log]) for a particular database
862: ** connection. See also [SQLITE_FCNTL_FILE_POINTER].
1.2 misho 863: **
1.3 misho 864: ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
1.4 misho 865: ** No longer in use.
866: **
867: ** <li>[[SQLITE_FCNTL_SYNC]]
868: ** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
869: ** sent to the VFS immediately before the xSync method is invoked on a
1.4.2.3 ! misho 870: ** database file descriptor. Or, if the xSync method is not invoked
! 871: ** because the user has configured SQLite with
! 872: ** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
1.4 misho 873: ** of the xSync method. In most cases, the pointer argument passed with
874: ** this file-control is NULL. However, if the database file is being synced
875: ** as part of a multi-database commit, the argument points to a nul-terminated
1.4.2.3 ! misho 876: ** string containing the transactions super-journal file name. VFSes that
! 877: ** do not need this signal should silently ignore this opcode. Applications
! 878: ** should not call [sqlite3_file_control()] with this opcode as doing so may
! 879: ** disrupt the operation of the specialized VFSes that do require it.
1.4 misho 880: **
881: ** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
882: ** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
883: ** and sent to the VFS after a transaction has been committed immediately
884: ** but before the database is unlocked. VFSes that do not need this signal
885: ** should silently ignore this opcode. Applications should not call
1.4.2.3 ! misho 886: ** [sqlite3_file_control()] with this opcode as doing so may disrupt the
! 887: ** operation of the specialized VFSes that do require it.
1.2 misho 888: **
1.3 misho 889: ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
1.2 misho 890: ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
891: ** retry counts and intervals for certain disk I/O operations for the
892: ** windows [VFS] in order to provide robustness in the presence of
893: ** anti-virus programs. By default, the windows VFS will retry file read,
894: ** file write, and file delete operations up to 10 times, with a delay
895: ** of 25 milliseconds before the first retry and with the delay increasing
896: ** by an additional 25 milliseconds with each subsequent retry. This
897: ** opcode allows these two values (10 retries and 25 milliseconds of delay)
898: ** to be adjusted. The values are changed for all database connections
899: ** within the same process. The argument is a pointer to an array of two
1.4.2.1 misho 900: ** integers where the first integer is the new retry count and the second
1.2 misho 901: ** integer is the delay. If either integer is negative, then the setting
902: ** is not changed but instead the prior value of that setting is written
903: ** into the array entry, allowing the current retry settings to be
904: ** interrogated. The zDbName parameter is ignored.
905: **
1.3 misho 906: ** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
1.2 misho 907: ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
1.3 misho 908: ** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary
1.4.2.2 misho 909: ** write ahead log ([WAL file]) and shared memory
910: ** files used for transaction control
1.2 misho 911: ** are automatically deleted when the latest connection to the database
912: ** closes. Setting persistent WAL mode causes those files to persist after
913: ** close. Persisting the files is useful when other processes that do not
914: ** have write permission on the directory containing the database file want
915: ** to read the database file, as the WAL and shared memory files must exist
916: ** in order for the database to be readable. The fourth parameter to
917: ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
918: ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
919: ** WAL mode. If the integer is -1, then it is overwritten with the current
920: ** WAL persistence setting.
921: **
1.3 misho 922: ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
1.2 misho 923: ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
924: ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting
925: ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
926: ** xDeviceCharacteristics methods. The fourth parameter to
927: ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
928: ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
929: ** mode. If the integer is -1, then it is overwritten with the current
930: ** zero-damage mode setting.
931: **
1.3 misho 932: ** <li>[[SQLITE_FCNTL_OVERWRITE]]
1.2 misho 933: ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
934: ** a write transaction to indicate that, unless it is rolled back for some
1.4.2.3 ! misho 935: ** reason, the entire database file will be overwritten by the current
1.2 misho 936: ** transaction. This is used by VACUUM operations.
937: **
1.3 misho 938: ** <li>[[SQLITE_FCNTL_VFSNAME]]
1.2 misho 939: ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
940: ** all [VFSes] in the VFS stack. The names are of all VFS shims and the
1.4.2.3 ! misho 941: ** final bottom-level VFS are written into memory obtained from
1.2 misho 942: ** [sqlite3_malloc()] and the result is stored in the char* variable
943: ** that the fourth parameter of [sqlite3_file_control()] points to.
944: ** The caller is responsible for freeing the memory when done. As with
945: ** all file-control actions, there is no guarantee that this will actually
946: ** do anything. Callers should initialize the char* variable to a NULL
947: ** pointer in case this file-control is not implemented. This file-control
948: ** is intended for diagnostic use only.
1.3 misho 949: **
1.4 misho 950: ** <li>[[SQLITE_FCNTL_VFS_POINTER]]
951: ** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
952: ** [VFSes] currently in use. ^(The argument X in
953: ** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
954: ** of type "[sqlite3_vfs] **". This opcodes will set *X
955: ** to a pointer to the top-level VFS.)^
956: ** ^When there are multiple VFS shims in the stack, this opcode finds the
957: ** upper-most shim only.
958: **
1.3 misho 959: ** <li>[[SQLITE_FCNTL_PRAGMA]]
1.4.2.3 ! misho 960: ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
1.3 misho 961: ** file control is sent to the open [sqlite3_file] object corresponding
962: ** to the database file to which the pragma statement refers. ^The argument
963: ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
964: ** pointers to strings (char**) in which the second element of the array
965: ** is the name of the pragma and the third element is the argument to the
966: ** pragma or NULL if the pragma has no argument. ^The handler for an
967: ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
968: ** of the char** argument point to a string obtained from [sqlite3_mprintf()]
969: ** or the equivalent and that string will become the result of the pragma or
970: ** the error message if the pragma fails. ^If the
1.4.2.3 ! misho 971: ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
1.3 misho 972: ** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA]
973: ** file control returns [SQLITE_OK], then the parser assumes that the
974: ** VFS has handled the PRAGMA itself and the parser generates a no-op
1.4 misho 975: ** prepared statement if result string is NULL, or that returns a copy
976: ** of the result string if the string is non-NULL.
977: ** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
1.3 misho 978: ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
979: ** that the VFS encountered an error while handling the [PRAGMA] and the
980: ** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA]
981: ** file control occurs at the beginning of pragma statement analysis and so
982: ** it is able to override built-in [PRAGMA] statements.
983: **
984: ** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
1.4 misho 985: ** ^The [SQLITE_FCNTL_BUSYHANDLER]
986: ** file-control may be invoked by SQLite on the database file handle
1.3 misho 987: ** shortly after it is opened in order to provide a custom VFS with access
1.4.2.3 ! misho 988: ** to the connection's busy-handler callback. The argument is of type (void**)
1.3 misho 989: ** - an array of two (void *) values. The first (void *) actually points
1.4.2.3 ! misho 990: ** to a function of type (int (*)(void *)). In order to invoke the connection's
1.3 misho 991: ** busy-handler, this function should be invoked with the second (void *) in
992: ** the array as the only argument. If it returns non-zero, then the operation
993: ** should be retried. If it returns zero, the custom VFS should abandon the
994: ** current operation.
995: **
996: ** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
1.4.2.3 ! misho 997: ** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
1.4 misho 998: ** to have SQLite generate a
1.3 misho 999: ** temporary filename using the same algorithm that is followed to generate
1000: ** temporary filenames for TEMP tables and other internal uses. The
1001: ** argument should be a char** which will be filled with the filename
1002: ** written into memory obtained from [sqlite3_malloc()]. The caller should
1003: ** invoke [sqlite3_free()] on the result to avoid a memory leak.
1004: **
1.4 misho 1005: ** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
1006: ** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
1007: ** maximum number of bytes that will be used for memory-mapped I/O.
1008: ** The argument is a pointer to a value of type sqlite3_int64 that
1009: ** is an advisory maximum number of bytes in the file to memory map. The
1010: ** pointer is overwritten with the old value. The limit is not changed if
1.4.2.3 ! misho 1011: ** the value originally pointed to is negative, and so the current limit
1.4 misho 1012: ** can be queried by passing in a pointer to a negative number. This
1013: ** file-control is used internally to implement [PRAGMA mmap_size].
1014: **
1015: ** <li>[[SQLITE_FCNTL_TRACE]]
1016: ** The [SQLITE_FCNTL_TRACE] file control provides advisory information
1017: ** to the VFS about what the higher layers of the SQLite stack are doing.
1018: ** This file control is used by some VFS activity tracing [shims].
1019: ** The argument is a zero-terminated string. Higher layers in the
1020: ** SQLite stack may generate instances of this file control if
1021: ** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
1022: **
1023: ** <li>[[SQLITE_FCNTL_HAS_MOVED]]
1024: ** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
1025: ** pointer to an integer and it writes a boolean into that integer depending
1026: ** on whether or not the file has been renamed, moved, or deleted since it
1027: ** was first opened.
1028: **
1.4.2.1 misho 1029: ** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]]
1030: ** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the
1031: ** underlying native file handle associated with a file handle. This file
1032: ** control interprets its argument as a pointer to a native file handle and
1033: ** writes the resulting value there.
1034: **
1.4 misho 1035: ** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
1036: ** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This
1037: ** opcode causes the xFileControl method to swap the file handle with the one
1038: ** pointed to by the pArg argument. This capability is used during testing
1039: ** and only needs to be supported when SQLITE_TEST is defined.
1040: **
1041: ** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
1042: ** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
1043: ** be advantageous to block on the next WAL lock if the lock is not immediately
1044: ** available. The WAL subsystem issues this signal during rare
1045: ** circumstances in order to fix a problem with priority inversion.
1046: ** Applications should <em>not</em> use this file-control.
1047: **
1048: ** <li>[[SQLITE_FCNTL_ZIPVFS]]
1049: ** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
1050: ** VFS should return SQLITE_NOTFOUND for this opcode.
1051: **
1052: ** <li>[[SQLITE_FCNTL_RBU]]
1053: ** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
1054: ** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for
1.4.2.3 ! misho 1055: ** this opcode.
1.4.2.2 misho 1056: **
1057: ** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]]
1058: ** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then
1059: ** the file descriptor is placed in "batch write mode", which
1060: ** means all subsequent write operations will be deferred and done
1061: ** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems
1062: ** that do not support batch atomic writes will return SQLITE_NOTFOUND.
1063: ** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to
1064: ** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or
1065: ** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make
1066: ** no VFS interface calls on the same [sqlite3_file] file descriptor
1067: ** except for calls to the xWrite method and the xFileControl method
1068: ** with [SQLITE_FCNTL_SIZE_HINT].
1069: **
1070: ** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]]
1071: ** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write
1.4.2.3 ! misho 1072: ** operations since the previous successful call to
1.4.2.2 misho 1073: ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically.
1074: ** This file control returns [SQLITE_OK] if and only if the writes were
1075: ** all performed successfully and have been committed to persistent storage.
1076: ** ^Regardless of whether or not it is successful, this file control takes
1077: ** the file descriptor out of batch write mode so that all subsequent
1078: ** write operations are independent.
1079: ** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without
1080: ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1081: **
1082: ** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]]
1083: ** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write
1.4.2.3 ! misho 1084: ** operations since the previous successful call to
1.4.2.2 misho 1085: ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back.
1086: ** ^This file control takes the file descriptor out of batch write mode
1087: ** so that all subsequent write operations are independent.
1088: ** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without
1089: ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1090: **
1091: ** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]]
1.4.2.3 ! misho 1092: ** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS
! 1093: ** to block for up to M milliseconds before failing when attempting to
! 1094: ** obtain a file lock using the xLock or xShmLock methods of the VFS.
! 1095: ** The parameter is a pointer to a 32-bit signed integer that contains
! 1096: ** the value that M is to be set to. Before returning, the 32-bit signed
! 1097: ** integer is overwritten with the previous value of M.
1.4.2.2 misho 1098: **
1099: ** <li>[[SQLITE_FCNTL_DATA_VERSION]]
1100: ** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to
1101: ** a database file. The argument is a pointer to a 32-bit unsigned integer.
1102: ** The "data version" for the pager is written into the pointer. The
1103: ** "data version" changes whenever any change occurs to the corresponding
1104: ** database file, either through SQL statements on the same database
1105: ** connection or through transactions committed by separate database
1106: ** connections possibly in other processes. The [sqlite3_total_changes()]
1107: ** interface can be used to find if any database on the connection has changed,
1108: ** but that interface responds to changes on TEMP as well as MAIN and does
1109: ** not provide a mechanism to detect changes to MAIN only. Also, the
1110: ** [sqlite3_total_changes()] interface responds to internal changes only and
1111: ** omits changes made by other database connections. The
1.4.2.3 ! misho 1112: ** [PRAGMA data_version] command provides a mechanism to detect changes to
1.4.2.2 misho 1113: ** a single attached database that occur due to other database connections,
1114: ** but omits changes implemented by the database connection on which it is
1115: ** called. This file control is the only mechanism to detect changes that
1116: ** happen either internally or externally and that are associated with
1117: ** a particular attached database.
1.4.2.3 ! misho 1118: **
! 1119: ** <li>[[SQLITE_FCNTL_CKPT_START]]
! 1120: ** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint
! 1121: ** in wal mode before the client starts to copy pages from the wal
! 1122: ** file to the database file.
! 1123: **
! 1124: ** <li>[[SQLITE_FCNTL_CKPT_DONE]]
! 1125: ** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint
! 1126: ** in wal mode after the client has finished copying pages from the wal
! 1127: ** file to the database file, but before the *-shm file is updated to
! 1128: ** record the fact that the pages have been checkpointed.
1.3 misho 1129: ** </ul>
1.2 misho 1130: */
1131: #define SQLITE_FCNTL_LOCKSTATE 1
1.4 misho 1132: #define SQLITE_FCNTL_GET_LOCKPROXYFILE 2
1133: #define SQLITE_FCNTL_SET_LOCKPROXYFILE 3
1134: #define SQLITE_FCNTL_LAST_ERRNO 4
1.2 misho 1135: #define SQLITE_FCNTL_SIZE_HINT 5
1136: #define SQLITE_FCNTL_CHUNK_SIZE 6
1137: #define SQLITE_FCNTL_FILE_POINTER 7
1138: #define SQLITE_FCNTL_SYNC_OMITTED 8
1139: #define SQLITE_FCNTL_WIN32_AV_RETRY 9
1140: #define SQLITE_FCNTL_PERSIST_WAL 10
1141: #define SQLITE_FCNTL_OVERWRITE 11
1142: #define SQLITE_FCNTL_VFSNAME 12
1143: #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13
1.3 misho 1144: #define SQLITE_FCNTL_PRAGMA 14
1145: #define SQLITE_FCNTL_BUSYHANDLER 15
1146: #define SQLITE_FCNTL_TEMPFILENAME 16
1.4 misho 1147: #define SQLITE_FCNTL_MMAP_SIZE 18
1148: #define SQLITE_FCNTL_TRACE 19
1149: #define SQLITE_FCNTL_HAS_MOVED 20
1150: #define SQLITE_FCNTL_SYNC 21
1151: #define SQLITE_FCNTL_COMMIT_PHASETWO 22
1152: #define SQLITE_FCNTL_WIN32_SET_HANDLE 23
1153: #define SQLITE_FCNTL_WAL_BLOCK 24
1154: #define SQLITE_FCNTL_ZIPVFS 25
1155: #define SQLITE_FCNTL_RBU 26
1156: #define SQLITE_FCNTL_VFS_POINTER 27
1157: #define SQLITE_FCNTL_JOURNAL_POINTER 28
1.4.2.1 misho 1158: #define SQLITE_FCNTL_WIN32_GET_HANDLE 29
1159: #define SQLITE_FCNTL_PDB 30
1.4.2.2 misho 1160: #define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31
1161: #define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32
1162: #define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33
1163: #define SQLITE_FCNTL_LOCK_TIMEOUT 34
1164: #define SQLITE_FCNTL_DATA_VERSION 35
1165: #define SQLITE_FCNTL_SIZE_LIMIT 36
1.4.2.3 ! misho 1166: #define SQLITE_FCNTL_CKPT_DONE 37
! 1167: #define SQLITE_FCNTL_RESERVE_BYTES 38
! 1168: #define SQLITE_FCNTL_CKPT_START 39
1.4 misho 1169:
1170: /* deprecated names */
1171: #define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE
1172: #define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE
1173: #define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO
1174:
1.2 misho 1175:
1176: /*
1177: ** CAPI3REF: Mutex Handle
1178: **
1179: ** The mutex module within SQLite defines [sqlite3_mutex] to be an
1180: ** abstract type for a mutex object. The SQLite core never looks
1181: ** at the internal representation of an [sqlite3_mutex]. It only
1182: ** deals with pointers to the [sqlite3_mutex] object.
1183: **
1184: ** Mutexes are created using [sqlite3_mutex_alloc()].
1185: */
1186: typedef struct sqlite3_mutex sqlite3_mutex;
1187:
1188: /*
1.4 misho 1189: ** CAPI3REF: Loadable Extension Thunk
1190: **
1191: ** A pointer to the opaque sqlite3_api_routines structure is passed as
1192: ** the third parameter to entry points of [loadable extensions]. This
1193: ** structure must be typedefed in order to work around compiler warnings
1194: ** on some platforms.
1195: */
1196: typedef struct sqlite3_api_routines sqlite3_api_routines;
1197:
1198: /*
1.2 misho 1199: ** CAPI3REF: OS Interface Object
1200: **
1201: ** An instance of the sqlite3_vfs object defines the interface between
1202: ** the SQLite core and the underlying operating system. The "vfs"
1203: ** in the name of the object stands for "virtual file system". See
1204: ** the [VFS | VFS documentation] for further information.
1205: **
1.4.2.2 misho 1206: ** The VFS interface is sometimes extended by adding new methods onto
1207: ** the end. Each time such an extension occurs, the iVersion field
1208: ** is incremented. The iVersion value started out as 1 in
1209: ** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2
1210: ** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased
1211: ** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields
1212: ** may be appended to the sqlite3_vfs object and the iVersion value
1213: ** may increase again in future versions of SQLite.
1.4.2.3 ! misho 1214: ** Note that due to an oversight, the structure
! 1215: ** of the sqlite3_vfs object changed in the transition from
1.4.2.2 misho 1216: ** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0]
1.4.2.3 ! misho 1217: ** and yet the iVersion field was not increased.
1.2 misho 1218: **
1219: ** The szOsFile field is the size of the subclassed [sqlite3_file]
1220: ** structure used by this VFS. mxPathname is the maximum length of
1221: ** a pathname in this VFS.
1222: **
1223: ** Registered sqlite3_vfs objects are kept on a linked list formed by
1224: ** the pNext pointer. The [sqlite3_vfs_register()]
1225: ** and [sqlite3_vfs_unregister()] interfaces manage this list
1226: ** in a thread-safe way. The [sqlite3_vfs_find()] interface
1227: ** searches the list. Neither the application code nor the VFS
1228: ** implementation should use the pNext pointer.
1229: **
1230: ** The pNext field is the only field in the sqlite3_vfs
1231: ** structure that SQLite will ever modify. SQLite will only access
1232: ** or modify this field while holding a particular static mutex.
1233: ** The application should never modify anything within the sqlite3_vfs
1234: ** object once the object has been registered.
1235: **
1236: ** The zName field holds the name of the VFS module. The name must
1237: ** be unique across all VFS modules.
1238: **
1239: ** [[sqlite3_vfs.xOpen]]
1240: ** ^SQLite guarantees that the zFilename parameter to xOpen
1241: ** is either a NULL pointer or string obtained
1242: ** from xFullPathname() with an optional suffix added.
1243: ** ^If a suffix is added to the zFilename parameter, it will
1244: ** consist of a single "-" character followed by no more than
1245: ** 11 alphanumeric and/or "-" characters.
1246: ** ^SQLite further guarantees that
1247: ** the string will be valid and unchanged until xClose() is
1248: ** called. Because of the previous sentence,
1249: ** the [sqlite3_file] can safely store a pointer to the
1250: ** filename if it needs to remember the filename for some reason.
1251: ** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1.4.2.3 ! misho 1252: ** must invent its own temporary name for the file. ^Whenever the
1.2 misho 1253: ** xFilename parameter is NULL it will also be the case that the
1254: ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1255: **
1256: ** The flags argument to xOpen() includes all bits set in
1257: ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
1258: ** or [sqlite3_open16()] is used, then flags includes at least
1.4.2.3 ! misho 1259: ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1.2 misho 1260: ** If xOpen() opens a file read-only then it sets *pOutFlags to
1261: ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
1262: **
1263: ** ^(SQLite will also add one of the following flags to the xOpen()
1264: ** call, depending on the object being opened:
1265: **
1266: ** <ul>
1267: ** <li> [SQLITE_OPEN_MAIN_DB]
1268: ** <li> [SQLITE_OPEN_MAIN_JOURNAL]
1269: ** <li> [SQLITE_OPEN_TEMP_DB]
1270: ** <li> [SQLITE_OPEN_TEMP_JOURNAL]
1271: ** <li> [SQLITE_OPEN_TRANSIENT_DB]
1272: ** <li> [SQLITE_OPEN_SUBJOURNAL]
1.4.2.3 ! misho 1273: ** <li> [SQLITE_OPEN_SUPER_JOURNAL]
1.2 misho 1274: ** <li> [SQLITE_OPEN_WAL]
1275: ** </ul>)^
1276: **
1277: ** The file I/O implementation can use the object type flags to
1278: ** change the way it deals with files. For example, an application
1279: ** that does not care about crash recovery or rollback might make
1280: ** the open of a journal file a no-op. Writes to this journal would
1281: ** also be no-ops, and any attempt to read the journal would return
1282: ** SQLITE_IOERR. Or the implementation might recognize that a database
1283: ** file will be doing page-aligned sector reads and writes in a random
1284: ** order and set up its I/O subsystem accordingly.
1285: **
1286: ** SQLite might also add one of the following flags to the xOpen method:
1287: **
1288: ** <ul>
1289: ** <li> [SQLITE_OPEN_DELETEONCLOSE]
1290: ** <li> [SQLITE_OPEN_EXCLUSIVE]
1291: ** </ul>
1292: **
1293: ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1294: ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]
1295: ** will be set for TEMP databases and their journals, transient
1296: ** databases, and subjournals.
1297: **
1298: ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1299: ** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1300: ** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1.4.2.3 ! misho 1301: ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1.2 misho 1302: ** SQLITE_OPEN_CREATE, is used to indicate that file should always
1303: ** be created, and that it is an error if it already exists.
1.4.2.3 ! misho 1304: ** It is <i>not</i> used to indicate the file should be opened
1.2 misho 1305: ** for exclusive access.
1306: **
1307: ** ^At least szOsFile bytes of memory are allocated by SQLite
1.4.2.3 ! misho 1308: ** to hold the [sqlite3_file] structure passed as the third
1.2 misho 1309: ** argument to xOpen. The xOpen method does not have to
1310: ** allocate the structure; it should just fill it in. Note that
1311: ** the xOpen method must set the sqlite3_file.pMethods to either
1312: ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
1313: ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
1314: ** element will be valid after xOpen returns regardless of the success
1315: ** or failure of the xOpen call.
1316: **
1317: ** [[sqlite3_vfs.xAccess]]
1318: ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1319: ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1320: ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1.4.2.2 misho 1321: ** to test whether a file is at least readable. The SQLITE_ACCESS_READ
1322: ** flag is never actually used and is not implemented in the built-in
1323: ** VFSes of SQLite. The file is named by the second argument and can be a
1324: ** directory. The xAccess method returns [SQLITE_OK] on success or some
1325: ** non-zero error code if there is an I/O error or if the name of
1326: ** the file given in the second argument is illegal. If SQLITE_OK
1327: ** is returned, then non-zero or zero is written into *pResOut to indicate
1.4.2.3 ! misho 1328: ** whether or not the file is accessible.
1.2 misho 1329: **
1330: ** ^SQLite will always allocate at least mxPathname+1 bytes for the
1331: ** output buffer xFullPathname. The exact size of the output buffer
1332: ** is also passed as a parameter to both methods. If the output buffer
1333: ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1334: ** handled as a fatal error by SQLite, vfs implementations should endeavor
1335: ** to prevent this by setting mxPathname to a sufficiently large value.
1336: **
1337: ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1338: ** interfaces are not strictly a part of the filesystem, but they are
1339: ** included in the VFS structure for completeness.
1340: ** The xRandomness() function attempts to return nBytes bytes
1341: ** of good-quality randomness into zOut. The return value is
1342: ** the actual number of bytes of randomness obtained.
1343: ** The xSleep() method causes the calling thread to sleep for at
1344: ** least the number of microseconds given. ^The xCurrentTime()
1345: ** method returns a Julian Day Number for the current date and time as
1346: ** a floating point value.
1347: ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1.4.2.3 ! misho 1348: ** Day Number multiplied by 86400000 (the number of milliseconds in
! 1349: ** a 24-hour day).
1.2 misho 1350: ** ^SQLite will use the xCurrentTimeInt64() method to get the current
1.4.2.3 ! misho 1351: ** date and time if that method is available (if iVersion is 2 or
1.2 misho 1352: ** greater and the function pointer is not NULL) and will fall back
1353: ** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1354: **
1355: ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1356: ** are not used by the SQLite core. These optional interfaces are provided
1.4.2.3 ! misho 1357: ** by some VFSes to facilitate testing of the VFS code. By overriding
1.2 misho 1358: ** system calls with functions under its control, a test program can
1359: ** simulate faults and error conditions that would otherwise be difficult
1360: ** or impossible to induce. The set of system calls that can be overridden
1361: ** varies from one VFS to another, and from one version of the same VFS to the
1362: ** next. Applications that use these interfaces must be prepared for any
1363: ** or all of these interfaces to be NULL or for their behavior to change
1364: ** from one release to the next. Applications must not attempt to access
1365: ** any of these methods if the iVersion of the VFS is less than 3.
1366: */
1367: typedef struct sqlite3_vfs sqlite3_vfs;
1368: typedef void (*sqlite3_syscall_ptr)(void);
1369: struct sqlite3_vfs {
1370: int iVersion; /* Structure version number (currently 3) */
1371: int szOsFile; /* Size of subclassed sqlite3_file */
1372: int mxPathname; /* Maximum file pathname length */
1373: sqlite3_vfs *pNext; /* Next registered VFS */
1374: const char *zName; /* Name of this virtual file system */
1375: void *pAppData; /* Pointer to application-specific data */
1376: int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
1377: int flags, int *pOutFlags);
1378: int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1379: int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1380: int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1381: void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1382: void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1383: void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1384: void (*xDlClose)(sqlite3_vfs*, void*);
1385: int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1386: int (*xSleep)(sqlite3_vfs*, int microseconds);
1387: int (*xCurrentTime)(sqlite3_vfs*, double*);
1388: int (*xGetLastError)(sqlite3_vfs*, int, char *);
1389: /*
1390: ** The methods above are in version 1 of the sqlite_vfs object
1391: ** definition. Those that follow are added in version 2 or later
1392: */
1393: int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1394: /*
1395: ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1396: ** Those below are for version 3 and greater.
1397: */
1398: int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1399: sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1400: const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1401: /*
1402: ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1.4 misho 1403: ** New fields may be appended in future versions. The iVersion
1.4.2.3 ! misho 1404: ** value will increment whenever this happens.
1.2 misho 1405: */
1406: };
1407:
1408: /*
1409: ** CAPI3REF: Flags for the xAccess VFS method
1410: **
1411: ** These integer constants can be used as the third parameter to
1412: ** the xAccess method of an [sqlite3_vfs] object. They determine
1413: ** what kind of permissions the xAccess method is looking for.
1414: ** With SQLITE_ACCESS_EXISTS, the xAccess method
1415: ** simply checks whether the file exists.
1416: ** With SQLITE_ACCESS_READWRITE, the xAccess method
1417: ** checks whether the named directory is both readable and writable
1418: ** (in other words, if files can be added, removed, and renamed within
1419: ** the directory).
1420: ** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1421: ** [temp_store_directory pragma], though this could change in a future
1422: ** release of SQLite.
1423: ** With SQLITE_ACCESS_READ, the xAccess method
1424: ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
1425: ** currently unused, though it might be used in a future release of
1426: ** SQLite.
1427: */
1428: #define SQLITE_ACCESS_EXISTS 0
1429: #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
1430: #define SQLITE_ACCESS_READ 2 /* Unused */
1431:
1432: /*
1433: ** CAPI3REF: Flags for the xShmLock VFS method
1434: **
1435: ** These integer constants define the various locking operations
1436: ** allowed by the xShmLock method of [sqlite3_io_methods]. The
1437: ** following are the only legal combinations of flags to the
1438: ** xShmLock method:
1439: **
1440: ** <ul>
1441: ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1442: ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1443: ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1444: ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1445: ** </ul>
1446: **
1447: ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1.4.2.3 ! misho 1448: ** was given on the corresponding lock.
1.2 misho 1449: **
1450: ** The xShmLock method can transition between unlocked and SHARED or
1451: ** between unlocked and EXCLUSIVE. It cannot transition between SHARED
1452: ** and EXCLUSIVE.
1453: */
1454: #define SQLITE_SHM_UNLOCK 1
1455: #define SQLITE_SHM_LOCK 2
1456: #define SQLITE_SHM_SHARED 4
1457: #define SQLITE_SHM_EXCLUSIVE 8
1458:
1459: /*
1460: ** CAPI3REF: Maximum xShmLock index
1461: **
1462: ** The xShmLock method on [sqlite3_io_methods] may use values
1463: ** between 0 and this upper bound as its "offset" argument.
1464: ** The SQLite core will never attempt to acquire or release a
1465: ** lock outside of this range
1466: */
1467: #define SQLITE_SHM_NLOCK 8
1468:
1469:
1470: /*
1471: ** CAPI3REF: Initialize The SQLite Library
1472: **
1473: ** ^The sqlite3_initialize() routine initializes the
1474: ** SQLite library. ^The sqlite3_shutdown() routine
1475: ** deallocates any resources that were allocated by sqlite3_initialize().
1476: ** These routines are designed to aid in process initialization and
1477: ** shutdown on embedded systems. Workstation applications using
1478: ** SQLite normally do not need to invoke either of these routines.
1479: **
1480: ** A call to sqlite3_initialize() is an "effective" call if it is
1481: ** the first time sqlite3_initialize() is invoked during the lifetime of
1482: ** the process, or if it is the first time sqlite3_initialize() is invoked
1483: ** following a call to sqlite3_shutdown(). ^(Only an effective call
1484: ** of sqlite3_initialize() does any initialization. All other calls
1485: ** are harmless no-ops.)^
1486: **
1487: ** A call to sqlite3_shutdown() is an "effective" call if it is the first
1488: ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
1489: ** an effective call to sqlite3_shutdown() does any deinitialization.
1490: ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1491: **
1492: ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1493: ** is not. The sqlite3_shutdown() interface must only be called from a
1494: ** single thread. All open [database connections] must be closed and all
1495: ** other SQLite resources must be deallocated prior to invoking
1496: ** sqlite3_shutdown().
1497: **
1498: ** Among other things, ^sqlite3_initialize() will invoke
1499: ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
1500: ** will invoke sqlite3_os_end().
1501: **
1502: ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1503: ** ^If for some reason, sqlite3_initialize() is unable to initialize
1504: ** the library (perhaps it is unable to allocate a needed resource such
1505: ** as a mutex) it returns an [error code] other than [SQLITE_OK].
1506: **
1507: ** ^The sqlite3_initialize() routine is called internally by many other
1508: ** SQLite interfaces so that an application usually does not need to
1509: ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
1510: ** calls sqlite3_initialize() so the SQLite library will be automatically
1511: ** initialized when [sqlite3_open()] is called if it has not be initialized
1512: ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1513: ** compile-time option, then the automatic calls to sqlite3_initialize()
1514: ** are omitted and the application must call sqlite3_initialize() directly
1515: ** prior to using any other SQLite interface. For maximum portability,
1516: ** it is recommended that applications always invoke sqlite3_initialize()
1517: ** directly prior to using any other SQLite interface. Future releases
1518: ** of SQLite may require this. In other words, the behavior exhibited
1519: ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1520: ** default behavior in some future release of SQLite.
1521: **
1522: ** The sqlite3_os_init() routine does operating-system specific
1523: ** initialization of the SQLite library. The sqlite3_os_end()
1524: ** routine undoes the effect of sqlite3_os_init(). Typical tasks
1525: ** performed by these routines include allocation or deallocation
1526: ** of static resources, initialization of global variables,
1527: ** setting up a default [sqlite3_vfs] module, or setting up
1528: ** a default configuration using [sqlite3_config()].
1529: **
1530: ** The application should never invoke either sqlite3_os_init()
1531: ** or sqlite3_os_end() directly. The application should only invoke
1532: ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
1533: ** interface is called automatically by sqlite3_initialize() and
1534: ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
1535: ** implementations for sqlite3_os_init() and sqlite3_os_end()
1536: ** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1537: ** When [custom builds | built for other platforms]
1538: ** (using the [SQLITE_OS_OTHER=1] compile-time
1539: ** option) the application must supply a suitable implementation for
1540: ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
1541: ** implementation of sqlite3_os_init() or sqlite3_os_end()
1542: ** must return [SQLITE_OK] on success and some other [error code] upon
1543: ** failure.
1544: */
1545: SQLITE_API int sqlite3_initialize(void);
1546: SQLITE_API int sqlite3_shutdown(void);
1547: SQLITE_API int sqlite3_os_init(void);
1548: SQLITE_API int sqlite3_os_end(void);
1549:
1550: /*
1551: ** CAPI3REF: Configuring The SQLite Library
1552: **
1553: ** The sqlite3_config() interface is used to make global configuration
1554: ** changes to SQLite in order to tune SQLite to the specific needs of
1555: ** the application. The default configuration is recommended for most
1556: ** applications and so this routine is usually not necessary. It is
1557: ** provided to support rare applications with unusual needs.
1558: **
1.4 misho 1559: ** <b>The sqlite3_config() interface is not threadsafe. The application
1560: ** must ensure that no other SQLite interfaces are invoked by other
1561: ** threads while sqlite3_config() is running.</b>
1562: **
1563: ** The sqlite3_config() interface
1.2 misho 1564: ** may only be invoked prior to library initialization using
1565: ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1566: ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1567: ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
1568: ** Note, however, that ^sqlite3_config() can be called as part of the
1569: ** implementation of an application-defined [sqlite3_os_init()].
1570: **
1571: ** The first argument to sqlite3_config() is an integer
1572: ** [configuration option] that determines
1573: ** what property of SQLite is to be configured. Subsequent arguments
1574: ** vary depending on the [configuration option]
1575: ** in the first argument.
1576: **
1577: ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1578: ** ^If the option is unknown or SQLite is unable to set the option
1579: ** then this routine returns a non-zero [error code].
1580: */
1581: SQLITE_API int sqlite3_config(int, ...);
1582:
1583: /*
1584: ** CAPI3REF: Configure database connections
1.4 misho 1585: ** METHOD: sqlite3
1.2 misho 1586: **
1587: ** The sqlite3_db_config() interface is used to make configuration
1588: ** changes to a [database connection]. The interface is similar to
1589: ** [sqlite3_config()] except that the changes apply to a single
1590: ** [database connection] (specified in the first argument).
1591: **
1592: ** The second argument to sqlite3_db_config(D,V,...) is the
1.4.2.3 ! misho 1593: ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
1.2 misho 1594: ** that indicates what aspect of the [database connection] is being configured.
1595: ** Subsequent arguments vary depending on the configuration verb.
1596: **
1597: ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1598: ** the call is considered successful.
1599: */
1600: SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
1601:
1602: /*
1603: ** CAPI3REF: Memory Allocation Routines
1604: **
1605: ** An instance of this object defines the interface between SQLite
1606: ** and low-level memory allocation routines.
1607: **
1608: ** This object is used in only one place in the SQLite interface.
1609: ** A pointer to an instance of this object is the argument to
1610: ** [sqlite3_config()] when the configuration option is
1.4.2.3 ! misho 1611: ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1.2 misho 1612: ** By creating an instance of this object
1613: ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1614: ** during configuration, an application can specify an alternative
1615: ** memory allocation subsystem for SQLite to use for all of its
1616: ** dynamic memory needs.
1617: **
1618: ** Note that SQLite comes with several [built-in memory allocators]
1619: ** that are perfectly adequate for the overwhelming majority of applications
1620: ** and that this object is only useful to a tiny minority of applications
1621: ** with specialized memory allocation requirements. This object is
1622: ** also used during testing of SQLite in order to specify an alternative
1623: ** memory allocator that simulates memory out-of-memory conditions in
1624: ** order to verify that SQLite recovers gracefully from such
1625: ** conditions.
1626: **
1627: ** The xMalloc, xRealloc, and xFree methods must work like the
1628: ** malloc(), realloc() and free() functions from the standard C library.
1629: ** ^SQLite guarantees that the second argument to
1630: ** xRealloc is always a value returned by a prior call to xRoundup.
1631: **
1632: ** xSize should return the allocated size of a memory allocation
1633: ** previously obtained from xMalloc or xRealloc. The allocated size
1634: ** is always at least as big as the requested size but may be larger.
1635: **
1636: ** The xRoundup method returns what would be the allocated size of
1637: ** a memory allocation given a particular requested size. Most memory
1638: ** allocators round up memory allocations at least to the next multiple
1639: ** of 8. Some allocators round up to a larger multiple or to a power of 2.
1640: ** Every memory allocation request coming in through [sqlite3_malloc()]
1.4.2.3 ! misho 1641: ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
1.2 misho 1642: ** that causes the corresponding memory allocation to fail.
1643: **
1.4 misho 1644: ** The xInit method initializes the memory allocator. For example,
1.4.2.3 ! misho 1645: ** it might allocate any required mutexes or initialize internal data
1.2 misho 1646: ** structures. The xShutdown method is invoked (indirectly) by
1647: ** [sqlite3_shutdown()] and should deallocate any resources acquired
1648: ** by xInit. The pAppData pointer is used as the only parameter to
1649: ** xInit and xShutdown.
1650: **
1.4.2.3 ! misho 1651: ** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes
1.2 misho 1652: ** the xInit method, so the xInit method need not be threadsafe. The
1653: ** xShutdown method is only called from [sqlite3_shutdown()] so it does
1654: ** not need to be threadsafe either. For all other methods, SQLite
1655: ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1656: ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1657: ** it is by default) and so the methods are automatically serialized.
1658: ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1659: ** methods must be threadsafe or else make their own arrangements for
1660: ** serialization.
1661: **
1662: ** SQLite will never invoke xInit() more than once without an intervening
1663: ** call to xShutdown().
1664: */
1665: typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1666: struct sqlite3_mem_methods {
1667: void *(*xMalloc)(int); /* Memory allocation function */
1668: void (*xFree)(void*); /* Free a prior allocation */
1669: void *(*xRealloc)(void*,int); /* Resize an allocation */
1670: int (*xSize)(void*); /* Return the size of an allocation */
1671: int (*xRoundup)(int); /* Round up request size to allocation size */
1672: int (*xInit)(void*); /* Initialize the memory allocator */
1673: void (*xShutdown)(void*); /* Deinitialize the memory allocator */
1674: void *pAppData; /* Argument to xInit() and xShutdown() */
1675: };
1676:
1677: /*
1678: ** CAPI3REF: Configuration Options
1679: ** KEYWORDS: {configuration option}
1680: **
1681: ** These constants are the available integer configuration options that
1682: ** can be passed as the first argument to the [sqlite3_config()] interface.
1683: **
1684: ** New configuration options may be added in future releases of SQLite.
1685: ** Existing configuration options might be discontinued. Applications
1686: ** should check the return code from [sqlite3_config()] to make sure that
1687: ** the call worked. The [sqlite3_config()] interface will return a
1688: ** non-zero [error code] if a discontinued or unsupported configuration option
1689: ** is invoked.
1690: **
1691: ** <dl>
1692: ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1693: ** <dd>There are no arguments to this option. ^This option sets the
1694: ** [threading mode] to Single-thread. In other words, it disables
1695: ** all mutexing and puts SQLite into a mode where it can only be used
1696: ** by a single thread. ^If SQLite is compiled with
1697: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1698: ** it is not possible to change the [threading mode] from its default
1.4.2.3 ! misho 1699: ** value of Single-thread and so [sqlite3_config()] will return
1.2 misho 1700: ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1701: ** configuration option.</dd>
1702: **
1703: ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1704: ** <dd>There are no arguments to this option. ^This option sets the
1705: ** [threading mode] to Multi-thread. In other words, it disables
1706: ** mutexing on [database connection] and [prepared statement] objects.
1707: ** The application is responsible for serializing access to
1708: ** [database connections] and [prepared statements]. But other mutexes
1709: ** are enabled so that SQLite will be safe to use in a multi-threaded
1710: ** environment as long as no two threads attempt to use the same
1711: ** [database connection] at the same time. ^If SQLite is compiled with
1712: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1713: ** it is not possible to set the Multi-thread [threading mode] and
1714: ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1715: ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1716: **
1717: ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1718: ** <dd>There are no arguments to this option. ^This option sets the
1719: ** [threading mode] to Serialized. In other words, this option enables
1720: ** all mutexes including the recursive
1721: ** mutexes on [database connection] and [prepared statement] objects.
1722: ** In this mode (which is the default when SQLite is compiled with
1723: ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1724: ** to [database connections] and [prepared statements] so that the
1725: ** application is free to use the same [database connection] or the
1726: ** same [prepared statement] in different threads at the same time.
1727: ** ^If SQLite is compiled with
1728: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1729: ** it is not possible to set the Serialized [threading mode] and
1730: ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1731: ** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1732: **
1733: ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1.4.2.3 ! misho 1734: ** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
1.4 misho 1735: ** a pointer to an instance of the [sqlite3_mem_methods] structure.
1736: ** The argument specifies
1.2 misho 1737: ** alternative low-level memory allocation routines to be used in place of
1738: ** the memory allocation routines built into SQLite.)^ ^SQLite makes
1739: ** its own private copy of the content of the [sqlite3_mem_methods] structure
1740: ** before the [sqlite3_config()] call returns.</dd>
1741: **
1742: ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1.4 misho 1743: ** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
1744: ** is a pointer to an instance of the [sqlite3_mem_methods] structure.
1745: ** The [sqlite3_mem_methods]
1.2 misho 1746: ** structure is filled with the currently defined memory allocation routines.)^
1747: ** This option can be used to overload the default memory allocation
1748: ** routines with a wrapper that simulations memory allocation failure or
1749: ** tracks memory usage, for example. </dd>
1750: **
1.4.2.2 misho 1751: ** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt>
1752: ** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of
1753: ** type int, interpreted as a boolean, which if true provides a hint to
1754: ** SQLite that it should avoid large memory allocations if possible.
1755: ** SQLite will run faster if it is free to make large memory allocations,
1756: ** but some application might prefer to run slower in exchange for
1757: ** guarantees about memory fragmentation that are possible if large
1758: ** allocations are avoided. This hint is normally off.
1759: ** </dd>
1760: **
1.2 misho 1761: ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1.4 misho 1762: ** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
1763: ** interpreted as a boolean, which enables or disables the collection of
1764: ** memory allocation statistics. ^(When memory allocation statistics are
1765: ** disabled, the following SQLite interfaces become non-operational:
1.2 misho 1766: ** <ul>
1.4.2.3 ! misho 1767: ** <li> [sqlite3_hard_heap_limit64()]
1.2 misho 1768: ** <li> [sqlite3_memory_used()]
1769: ** <li> [sqlite3_memory_highwater()]
1770: ** <li> [sqlite3_soft_heap_limit64()]
1.4 misho 1771: ** <li> [sqlite3_status64()]
1.2 misho 1772: ** </ul>)^
1773: ** ^Memory allocation statistics are enabled by default unless SQLite is
1774: ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1775: ** allocation statistics are disabled by default.
1776: ** </dd>
1777: **
1778: ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1.4.2.2 misho 1779: ** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used.
1.4 misho 1780: ** </dd>
1.2 misho 1781: **
1782: ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1.4 misho 1783: ** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
1784: ** that SQLite can use for the database page cache with the default page
1.4.2.3 ! misho 1785: ** cache implementation.
! 1786: ** This configuration option is a no-op if an application-defined page
1.4 misho 1787: ** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
1788: ** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
1789: ** 8-byte aligned memory (pMem), the size of each page cache line (sz),
1790: ** and the number of cache lines (N).
1.2 misho 1791: ** The sz argument should be the size of the largest database page
1.4 misho 1792: ** (a power of two between 512 and 65536) plus some extra bytes for each
1793: ** page header. ^The number of extra bytes needed by the page header
1794: ** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
1795: ** ^It is harmless, apart from the wasted memory,
1796: ** for the sz parameter to be larger than necessary. The pMem
1797: ** argument must be either a NULL pointer or a pointer to an 8-byte
1798: ** aligned block of memory of at least sz*N bytes, otherwise
1799: ** subsequent behavior is undefined.
1800: ** ^When pMem is not NULL, SQLite will strive to use the memory provided
1801: ** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
1802: ** a page cache line is larger than sz bytes or if all of the pMem buffer
1803: ** is exhausted.
1804: ** ^If pMem is NULL and N is non-zero, then each database connection
1805: ** does an initial bulk allocation for page cache memory
1806: ** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
1807: ** of -1024*N bytes if N is negative, . ^If additional
1808: ** page cache memory is needed beyond what is provided by the initial
1809: ** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
1810: ** additional cache line. </dd>
1.2 misho 1811: **
1812: ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1.4.2.3 ! misho 1813: ** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
1.4 misho 1814: ** that SQLite will use for all of its dynamic memory allocation needs
1.4.2.2 misho 1815: ** beyond those provided for by [SQLITE_CONFIG_PAGECACHE].
1.4 misho 1816: ** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
1817: ** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
1818: ** [SQLITE_ERROR] if invoked otherwise.
1819: ** ^There are three arguments to SQLITE_CONFIG_HEAP:
1820: ** An 8-byte aligned pointer to the memory,
1.2 misho 1821: ** the number of bytes in the memory buffer, and the minimum allocation size.
1822: ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1823: ** to using its default memory allocator (the system malloc() implementation),
1824: ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
1.4 misho 1825: ** memory pointer is not NULL then the alternative memory
1.2 misho 1826: ** allocator is engaged to handle all of SQLites memory allocation needs.
1827: ** The first pointer (the memory pointer) must be aligned to an 8-byte
1828: ** boundary or subsequent behavior of SQLite will be undefined.
1829: ** The minimum allocation size is capped at 2**12. Reasonable values
1830: ** for the minimum allocation size are 2**5 through 2**8.</dd>
1831: **
1832: ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1.4 misho 1833: ** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
1834: ** pointer to an instance of the [sqlite3_mutex_methods] structure.
1835: ** The argument specifies alternative low-level mutex routines to be used
1836: ** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of
1837: ** the content of the [sqlite3_mutex_methods] structure before the call to
1.2 misho 1838: ** [sqlite3_config()] returns. ^If SQLite is compiled with
1839: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1840: ** the entire mutexing subsystem is omitted from the build and hence calls to
1841: ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1842: ** return [SQLITE_ERROR].</dd>
1843: **
1844: ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1.4 misho 1845: ** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
1846: ** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The
1.2 misho 1847: ** [sqlite3_mutex_methods]
1848: ** structure is filled with the currently defined mutex routines.)^
1849: ** This option can be used to overload the default mutex allocation
1850: ** routines with a wrapper used to track mutex usage for performance
1851: ** profiling or testing, for example. ^If SQLite is compiled with
1852: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1853: ** the entire mutexing subsystem is omitted from the build and hence calls to
1854: ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1855: ** return [SQLITE_ERROR].</dd>
1856: **
1857: ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1.4 misho 1858: ** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
1859: ** the default size of lookaside memory on each [database connection].
1860: ** The first argument is the
1.2 misho 1861: ** size of each lookaside buffer slot and the second is the number of
1.4 misho 1862: ** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE
1863: ** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
1864: ** option to [sqlite3_db_config()] can be used to change the lookaside
1.2 misho 1865: ** configuration on individual connections.)^ </dd>
1866: **
1867: ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
1.4.2.3 ! misho 1868: ** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
1.4 misho 1869: ** a pointer to an [sqlite3_pcache_methods2] object. This object specifies
1870: ** the interface to a custom page cache implementation.)^
1871: ** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
1.2 misho 1872: **
1873: ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
1.4 misho 1874: ** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
1875: ** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of
1876: ** the current page cache implementation into that object.)^ </dd>
1.2 misho 1877: **
1878: ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
1.4 misho 1879: ** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
1880: ** global [error log].
1881: ** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1.4.2.3 ! misho 1882: ** function with a call signature of void(*)(void*,int,const char*),
1.2 misho 1883: ** and a pointer to void. ^If the function pointer is not NULL, it is
1884: ** invoked by [sqlite3_log()] to process each logging event. ^If the
1885: ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
1886: ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
1887: ** passed through as the first parameter to the application-defined logger
1888: ** function whenever that function is invoked. ^The second parameter to
1889: ** the logger function is a copy of the first parameter to the corresponding
1890: ** [sqlite3_log()] call and is intended to be a [result code] or an
1891: ** [extended result code]. ^The third parameter passed to the logger is
1892: ** log message after formatting via [sqlite3_snprintf()].
1893: ** The SQLite logging interface is not reentrant; the logger function
1894: ** supplied by the application must not invoke any SQLite interface.
1895: ** In a multi-threaded application, the application-defined logger
1896: ** function must be threadsafe. </dd>
1897: **
1898: ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
1.4 misho 1899: ** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
1900: ** If non-zero, then URI handling is globally enabled. If the parameter is zero,
1901: ** then URI handling is globally disabled.)^ ^If URI handling is globally
1902: ** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
1903: ** [sqlite3_open16()] or
1.2 misho 1904: ** specified as part of [ATTACH] commands are interpreted as URIs, regardless
1905: ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
1.4 misho 1906: ** connection is opened. ^If it is globally disabled, filenames are
1.2 misho 1907: ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
1.4 misho 1908: ** database connection is opened. ^(By default, URI handling is globally
1.2 misho 1909: ** disabled. The default value may be changed by compiling with the
1.4 misho 1910: ** [SQLITE_USE_URI] symbol defined.)^
1.2 misho 1911: **
1.3 misho 1912: ** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
1.4 misho 1913: ** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
1914: ** argument which is interpreted as a boolean in order to enable or disable
1915: ** the use of covering indices for full table scans in the query optimizer.
1916: ** ^The default setting is determined
1.3 misho 1917: ** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
1918: ** if that compile-time option is omitted.
1919: ** The ability to disable the use of covering indices for full table scans
1920: ** is because some incorrectly coded legacy applications might malfunction
1.4 misho 1921: ** when the optimization is enabled. Providing the ability to
1.3 misho 1922: ** disable the optimization allows the older, buggy application code to work
1923: ** without change even with newer versions of SQLite.
1924: **
1.2 misho 1925: ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
1.3 misho 1926: ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
1.2 misho 1927: ** <dd> These options are obsolete and should not be used by new code.
1928: ** They are retained for backwards compatibility but are now no-ops.
1.4 misho 1929: ** </dd>
1.3 misho 1930: **
1931: ** [[SQLITE_CONFIG_SQLLOG]]
1932: ** <dt>SQLITE_CONFIG_SQLLOG
1933: ** <dd>This option is only available if sqlite is compiled with the
1.4 misho 1934: ** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
1.3 misho 1935: ** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
1936: ** The second should be of type (void*). The callback is invoked by the library
1937: ** in three separate circumstances, identified by the value passed as the
1938: ** fourth parameter. If the fourth parameter is 0, then the database connection
1939: ** passed as the second argument has just been opened. The third argument
1940: ** points to a buffer containing the name of the main database file. If the
1941: ** fourth parameter is 1, then the SQL statement that the third parameter
1942: ** points to has just been executed. Or, if the fourth parameter is 2, then
1943: ** the connection being passed as the second parameter is being closed. The
1.4 misho 1944: ** third parameter is passed NULL In this case. An example of using this
1945: ** configuration option can be seen in the "test_sqllog.c" source file in
1946: ** the canonical SQLite source tree.</dd>
1947: **
1948: ** [[SQLITE_CONFIG_MMAP_SIZE]]
1949: ** <dt>SQLITE_CONFIG_MMAP_SIZE
1950: ** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
1951: ** that are the default mmap size limit (the default setting for
1952: ** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
1953: ** ^The default setting can be overridden by each database connection using
1954: ** either the [PRAGMA mmap_size] command, or by using the
1955: ** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size
1956: ** will be silently truncated if necessary so that it does not exceed the
1957: ** compile-time maximum mmap size set by the
1958: ** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
1959: ** ^If either argument to this option is negative, then that argument is
1960: ** changed to its compile-time default.
1961: **
1962: ** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
1963: ** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
1964: ** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
1965: ** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
1966: ** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
1967: ** that specifies the maximum size of the created heap.
1968: **
1969: ** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
1970: ** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
1971: ** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
1972: ** is a pointer to an integer and writes into that integer the number of extra
1973: ** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
1974: ** The amount of extra space required can change depending on the compiler,
1975: ** target platform, and SQLite version.
1976: **
1977: ** [[SQLITE_CONFIG_PMASZ]]
1978: ** <dt>SQLITE_CONFIG_PMASZ
1979: ** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
1980: ** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
1981: ** sorter to that integer. The default minimum PMA Size is set by the
1982: ** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched
1983: ** to help with sort operations when multithreaded sorting
1984: ** is enabled (using the [PRAGMA threads] command) and the amount of content
1985: ** to be sorted exceeds the page size times the minimum of the
1986: ** [PRAGMA cache_size] setting and this value.
1987: **
1988: ** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
1989: ** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
1990: ** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
1.4.2.3 ! misho 1991: ** becomes the [statement journal] spill-to-disk threshold.
1.4 misho 1992: ** [Statement journals] are held in memory until their size (in bytes)
1993: ** exceeds this threshold, at which point they are written to disk.
1994: ** Or if the threshold is -1, statement journals are always held
1995: ** exclusively in memory.
1996: ** Since many statement journals never become large, setting the spill
1997: ** threshold to a value such as 64KiB can greatly reduce the amount of
1998: ** I/O required to support statement rollback.
1999: ** The default value for this setting is controlled by the
2000: ** [SQLITE_STMTJRNL_SPILL] compile-time option.
1.4.2.2 misho 2001: **
2002: ** [[SQLITE_CONFIG_SORTERREF_SIZE]]
2003: ** <dt>SQLITE_CONFIG_SORTERREF_SIZE
2004: ** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter
2005: ** of type (int) - the new value of the sorter-reference size threshold.
2006: ** Usually, when SQLite uses an external sort to order records according
2007: ** to an ORDER BY clause, all fields required by the caller are present in the
2008: ** sorted records. However, if SQLite determines based on the declared type
2009: ** of a table column that its values are likely to be very large - larger
2010: ** than the configured sorter-reference size threshold - then a reference
2011: ** is stored in each sorted record and the required column values loaded
2012: ** from the database as records are returned in sorted order. The default
1.4.2.3 ! misho 2013: ** value for this option is to never use this optimization. Specifying a
1.4.2.2 misho 2014: ** negative value for this option restores the default behaviour.
2015: ** This option is only available if SQLite is compiled with the
2016: ** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option.
2017: **
2018: ** [[SQLITE_CONFIG_MEMDB_MAXSIZE]]
2019: ** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE
2020: ** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter
2021: ** [sqlite3_int64] parameter which is the default maximum size for an in-memory
2022: ** database created using [sqlite3_deserialize()]. This default maximum
2023: ** size can be adjusted up or down for individual databases using the
2024: ** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this
2025: ** configuration setting is never used, then the default maximum is determined
2026: ** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that
2027: ** compile-time option is not set, then the default maximum is 1073741824.
1.3 misho 2028: ** </dl>
1.2 misho 2029: */
2030: #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
2031: #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
2032: #define SQLITE_CONFIG_SERIALIZED 3 /* nil */
2033: #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
2034: #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
1.4.2.2 misho 2035: #define SQLITE_CONFIG_SCRATCH 6 /* No longer used */
1.2 misho 2036: #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
2037: #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
2038: #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
2039: #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
2040: #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
1.4.2.3 ! misho 2041: /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
1.2 misho 2042: #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
2043: #define SQLITE_CONFIG_PCACHE 14 /* no-op */
2044: #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */
2045: #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
2046: #define SQLITE_CONFIG_URI 17 /* int */
2047: #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */
2048: #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */
1.3 misho 2049: #define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */
2050: #define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */
1.4 misho 2051: #define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */
2052: #define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */
2053: #define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */
2054: #define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */
2055: #define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */
1.4.2.2 misho 2056: #define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */
2057: #define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */
2058: #define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */
1.2 misho 2059:
2060: /*
2061: ** CAPI3REF: Database Connection Configuration Options
2062: **
2063: ** These constants are the available integer configuration options that
2064: ** can be passed as the second argument to the [sqlite3_db_config()] interface.
2065: **
2066: ** New configuration options may be added in future releases of SQLite.
2067: ** Existing configuration options might be discontinued. Applications
2068: ** should check the return code from [sqlite3_db_config()] to make sure that
2069: ** the call worked. ^The [sqlite3_db_config()] interface will return a
2070: ** non-zero [error code] if a discontinued or unsupported configuration option
2071: ** is invoked.
2072: **
2073: ** <dl>
1.4.2.2 misho 2074: ** [[SQLITE_DBCONFIG_LOOKASIDE]]
1.2 misho 2075: ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
1.4.2.3 ! misho 2076: ** <dd> ^This option takes three additional arguments that determine the
1.2 misho 2077: ** [lookaside memory allocator] configuration for the [database connection].
2078: ** ^The first argument (the third parameter to [sqlite3_db_config()] is a
2079: ** pointer to a memory buffer to use for lookaside memory.
2080: ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
2081: ** may be NULL in which case SQLite will allocate the
2082: ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
2083: ** size of each lookaside buffer slot. ^The third argument is the number of
2084: ** slots. The size of the buffer in the first argument must be greater than
2085: ** or equal to the product of the second and third arguments. The buffer
2086: ** must be aligned to an 8-byte boundary. ^If the second argument to
2087: ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
2088: ** rounded down to the next smaller multiple of 8. ^(The lookaside memory
2089: ** configuration for a database connection can only be changed when that
2090: ** connection is not currently using lookaside memory, or in other words
2091: ** when the "current value" returned by
2092: ** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
2093: ** Any attempt to change the lookaside memory configuration when lookaside
1.4.2.3 ! misho 2094: ** memory is in use leaves the configuration unchanged and returns
1.2 misho 2095: ** [SQLITE_BUSY].)^</dd>
2096: **
1.4.2.2 misho 2097: ** [[SQLITE_DBCONFIG_ENABLE_FKEY]]
1.2 misho 2098: ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
2099: ** <dd> ^This option is used to enable or disable the enforcement of
2100: ** [foreign key constraints]. There should be two additional arguments.
2101: ** The first argument is an integer which is 0 to disable FK enforcement,
2102: ** positive to enable FK enforcement or negative to leave FK enforcement
2103: ** unchanged. The second parameter is a pointer to an integer into which
2104: ** is written 0 or 1 to indicate whether FK enforcement is off or on
2105: ** following this call. The second parameter may be a NULL pointer, in
2106: ** which case the FK enforcement setting is not reported back. </dd>
2107: **
1.4.2.2 misho 2108: ** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]]
1.2 misho 2109: ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
2110: ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
2111: ** There should be two additional arguments.
2112: ** The first argument is an integer which is 0 to disable triggers,
2113: ** positive to enable triggers or negative to leave the setting unchanged.
2114: ** The second parameter is a pointer to an integer into which
2115: ** is written 0 or 1 to indicate whether triggers are disabled or enabled
2116: ** following this call. The second parameter may be a NULL pointer, in
2117: ** which case the trigger setting is not reported back. </dd>
2118: **
1.4.2.3 ! misho 2119: ** [[SQLITE_DBCONFIG_ENABLE_VIEW]]
! 2120: ** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt>
! 2121: ** <dd> ^This option is used to enable or disable [CREATE VIEW | views].
! 2122: ** There should be two additional arguments.
! 2123: ** The first argument is an integer which is 0 to disable views,
! 2124: ** positive to enable views or negative to leave the setting unchanged.
! 2125: ** The second parameter is a pointer to an integer into which
! 2126: ** is written 0 or 1 to indicate whether views are disabled or enabled
! 2127: ** following this call. The second parameter may be a NULL pointer, in
! 2128: ** which case the view setting is not reported back. </dd>
! 2129: **
1.4.2.2 misho 2130: ** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]]
1.4 misho 2131: ** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
1.4.2.2 misho 2132: ** <dd> ^This option is used to enable or disable the
2133: ** [fts3_tokenizer()] function which is part of the
1.4 misho 2134: ** [FTS3] full-text search engine extension.
2135: ** There should be two additional arguments.
2136: ** The first argument is an integer which is 0 to disable fts3_tokenizer() or
2137: ** positive to enable fts3_tokenizer() or negative to leave the setting
2138: ** unchanged.
2139: ** The second parameter is a pointer to an integer into which
2140: ** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled
2141: ** following this call. The second parameter may be a NULL pointer, in
2142: ** which case the new setting is not reported back. </dd>
2143: **
1.4.2.2 misho 2144: ** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]]
1.4 misho 2145: ** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>
2146: ** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]
2147: ** interface independently of the [load_extension()] SQL function.
2148: ** The [sqlite3_enable_load_extension()] API enables or disables both the
2149: ** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
2150: ** There should be two additional arguments.
2151: ** When the first argument to this interface is 1, then only the C-API is
2152: ** enabled and the SQL function remains disabled. If the first argument to
2153: ** this interface is 0, then both the C-API and the SQL function are disabled.
2154: ** If the first argument is -1, then no changes are made to state of either the
2155: ** C-API or the SQL function.
2156: ** The second parameter is a pointer to an integer into which
2157: ** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
2158: ** is disabled or enabled following this call. The second parameter may
2159: ** be a NULL pointer, in which case the new setting is not reported back.
2160: ** </dd>
2161: **
1.4.2.2 misho 2162: ** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>
1.4.2.1 misho 2163: ** <dd> ^This option is used to change the name of the "main" database
2164: ** schema. ^The sole argument is a pointer to a constant UTF8 string
2165: ** which will become the new schema name in place of "main". ^SQLite
2166: ** does not make a copy of the new main schema name string, so the application
2167: ** must ensure that the argument passed into this DBCONFIG option is unchanged
2168: ** until after the database connection closes.
2169: ** </dd>
2170: **
1.4.2.3 ! misho 2171: ** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]]
1.4.2.1 misho 2172: ** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
1.4.2.3 ! misho 2173: ** <dd> Usually, when a database in wal mode is closed or detached from a
! 2174: ** database handle, SQLite checks if this will mean that there are now no
! 2175: ** connections at all to the database. If so, it performs a checkpoint
1.4.2.1 misho 2176: ** operation before closing the connection. This option may be used to
2177: ** override this behaviour. The first parameter passed to this operation
1.4.2.2 misho 2178: ** is an integer - positive to disable checkpoints-on-close, or zero (the
2179: ** default) to enable them, and negative to leave the setting unchanged.
2180: ** The second parameter is a pointer to an integer
1.4.2.1 misho 2181: ** into which is written 0 or 1 to indicate whether checkpoints-on-close
2182: ** have been disabled - 0 if they are not disabled, 1 if they are.
2183: ** </dd>
2184: **
1.4.2.2 misho 2185: ** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt>
2186: ** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates
2187: ** the [query planner stability guarantee] (QPSG). When the QPSG is active,
2188: ** a single SQL query statement will always use the same algorithm regardless
2189: ** of values of [bound parameters].)^ The QPSG disables some query optimizations
2190: ** that look at the values of bound parameters, which can make some queries
2191: ** slower. But the QPSG has the advantage of more predictable behavior. With
2192: ** the QPSG active, SQLite will always use the same query plan in the field as
2193: ** was used during testing in the lab.
1.4.2.3 ! misho 2194: ** The first argument to this setting is an integer which is 0 to disable
1.4.2.2 misho 2195: ** the QPSG, positive to enable QPSG, or negative to leave the setting
2196: ** unchanged. The second parameter is a pointer to an integer into which
2197: ** is written 0 or 1 to indicate whether the QPSG is disabled or enabled
2198: ** following this call.
2199: ** </dd>
2200: **
2201: ** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt>
1.4.2.3 ! misho 2202: ** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not
1.4.2.2 misho 2203: ** include output for any operations performed by trigger programs. This
2204: ** option is used to set or clear (the default) a flag that governs this
2205: ** behavior. The first parameter passed to this operation is an integer -
2206: ** positive to enable output for trigger programs, or zero to disable it,
2207: ** or negative to leave the setting unchanged.
1.4.2.3 ! misho 2208: ** The second parameter is a pointer to an integer into which is written
! 2209: ** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if
! 2210: ** it is not disabled, 1 if it is.
1.4.2.2 misho 2211: ** </dd>
2212: **
2213: ** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt>
2214: ** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run
2215: ** [VACUUM] in order to reset a database back to an empty database
2216: ** with no schema and no content. The following process works even for
2217: ** a badly corrupted database file:
2218: ** <ol>
2219: ** <li> If the database connection is newly opened, make sure it has read the
2220: ** database schema by preparing then discarding some query against the
2221: ** database, or calling sqlite3_table_column_metadata(), ignoring any
2222: ** errors. This step is only necessary if the application desires to keep
2223: ** the database in WAL mode after the reset if it was in WAL mode before
1.4.2.3 ! misho 2224: ** the reset.
1.4.2.2 misho 2225: ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0);
2226: ** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0);
2227: ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0);
2228: ** </ol>
2229: ** Because resetting a database is destructive and irreversible, the
2230: ** process requires the use of this obscure API and multiple steps to help
2231: ** ensure that it does not happen by accident.
2232: **
2233: ** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt>
2234: ** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the
2235: ** "defensive" flag for a database connection. When the defensive
1.4.2.3 ! misho 2236: ** flag is enabled, language features that allow ordinary SQL to
1.4.2.2 misho 2237: ** deliberately corrupt the database file are disabled. The disabled
2238: ** features include but are not limited to the following:
2239: ** <ul>
2240: ** <li> The [PRAGMA writable_schema=ON] statement.
2241: ** <li> The [PRAGMA journal_mode=OFF] statement.
2242: ** <li> Writes to the [sqlite_dbpage] virtual table.
2243: ** <li> Direct writes to [shadow tables].
2244: ** </ul>
2245: ** </dd>
2246: **
2247: ** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt>
2248: ** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the
2249: ** "writable_schema" flag. This has the same effect and is logically equivalent
2250: ** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF].
1.4.2.3 ! misho 2251: ** The first argument to this setting is an integer which is 0 to disable
1.4.2.2 misho 2252: ** the writable_schema, positive to enable writable_schema, or negative to
2253: ** leave the setting unchanged. The second parameter is a pointer to an
2254: ** integer into which is written 0 or 1 to indicate whether the writable_schema
2255: ** is enabled or disabled following this call.
2256: ** </dd>
2257: **
2258: ** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]]
2259: ** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt>
2260: ** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates
2261: ** the legacy behavior of the [ALTER TABLE RENAME] command such it
2262: ** behaves as it did prior to [version 3.24.0] (2018-06-04). See the
2263: ** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for
2264: ** additional information. This feature can also be turned on and off
2265: ** using the [PRAGMA legacy_alter_table] statement.
2266: ** </dd>
2267: **
2268: ** [[SQLITE_DBCONFIG_DQS_DML]]
2269: ** <dt>SQLITE_DBCONFIG_DQS_DML</td>
2270: ** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates
1.4.2.3 ! misho 2271: ** the legacy [double-quoted string literal] misfeature for DML statements
1.4.2.2 misho 2272: ** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The
2273: ** default value of this setting is determined by the [-DSQLITE_DQS]
2274: ** compile-time option.
2275: ** </dd>
2276: **
2277: ** [[SQLITE_DBCONFIG_DQS_DDL]]
2278: ** <dt>SQLITE_DBCONFIG_DQS_DDL</td>
2279: ** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates
2280: ** the legacy [double-quoted string literal] misfeature for DDL statements,
2281: ** such as CREATE TABLE and CREATE INDEX. The
2282: ** default value of this setting is determined by the [-DSQLITE_DQS]
2283: ** compile-time option.
2284: ** </dd>
1.4.2.3 ! misho 2285: **
! 2286: ** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]]
! 2287: ** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</td>
! 2288: ** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to
! 2289: ** assume that database schemas are untainted by malicious content.
! 2290: ** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite
! 2291: ** takes additional defensive steps to protect the application from harm
! 2292: ** including:
! 2293: ** <ul>
! 2294: ** <li> Prohibit the use of SQL functions inside triggers, views,
! 2295: ** CHECK constraints, DEFAULT clauses, expression indexes,
! 2296: ** partial indexes, or generated columns
! 2297: ** unless those functions are tagged with [SQLITE_INNOCUOUS].
! 2298: ** <li> Prohibit the use of virtual tables inside of triggers or views
! 2299: ** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS].
! 2300: ** </ul>
! 2301: ** This setting defaults to "on" for legacy compatibility, however
! 2302: ** all applications are advised to turn it off if possible. This setting
! 2303: ** can also be controlled using the [PRAGMA trusted_schema] statement.
! 2304: ** </dd>
! 2305: **
! 2306: ** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]]
! 2307: ** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</td>
! 2308: ** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates
! 2309: ** the legacy file format flag. When activated, this flag causes all newly
! 2310: ** created database file to have a schema format version number (the 4-byte
! 2311: ** integer found at offset 44 into the database header) of 1. This in turn
! 2312: ** means that the resulting database file will be readable and writable by
! 2313: ** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting,
! 2314: ** newly created databases are generally not understandable by SQLite versions
! 2315: ** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there
! 2316: ** is now scarcely any need to generated database files that are compatible
! 2317: ** all the way back to version 3.0.0, and so this setting is of little
! 2318: ** practical use, but is provided so that SQLite can continue to claim the
! 2319: ** ability to generate new database files that are compatible with version
! 2320: ** 3.0.0.
! 2321: ** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on,
! 2322: ** the [VACUUM] command will fail with an obscure error when attempting to
! 2323: ** process a table with generated columns and a descending index. This is
! 2324: ** not considered a bug since SQLite versions 3.3.0 and earlier do not support
! 2325: ** either generated columns or decending indexes.
! 2326: ** </dd>
1.2 misho 2327: ** </dl>
2328: */
1.4.2.1 misho 2329: #define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */
1.4 misho 2330: #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
2331: #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */
2332: #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */
2333: #define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
2334: #define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
1.4.2.1 misho 2335: #define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */
1.4.2.2 misho 2336: #define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */
2337: #define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */
2338: #define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */
2339: #define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */
2340: #define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */
2341: #define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */
2342: #define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */
2343: #define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */
1.4.2.3 ! misho 2344: #define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */
! 2345: #define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */
! 2346: #define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */
! 2347: #define SQLITE_DBCONFIG_MAX 1017 /* Largest DBCONFIG */
1.2 misho 2348:
2349: /*
2350: ** CAPI3REF: Enable Or Disable Extended Result Codes
1.4 misho 2351: ** METHOD: sqlite3
1.2 misho 2352: **
2353: ** ^The sqlite3_extended_result_codes() routine enables or disables the
2354: ** [extended result codes] feature of SQLite. ^The extended result
2355: ** codes are disabled by default for historical compatibility.
2356: */
2357: SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
2358:
2359: /*
2360: ** CAPI3REF: Last Insert Rowid
1.4 misho 2361: ** METHOD: sqlite3
1.2 misho 2362: **
1.4 misho 2363: ** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
2364: ** has a unique 64-bit signed
1.2 misho 2365: ** integer key called the [ROWID | "rowid"]. ^The rowid is always available
2366: ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
2367: ** names are not also used by explicitly declared columns. ^If
2368: ** the table has a column of type [INTEGER PRIMARY KEY] then that column
2369: ** is another alias for the rowid.
2370: **
1.4.2.1 misho 2371: ** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of
2372: ** the most recent successful [INSERT] into a rowid table or [virtual table]
2373: ** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not
1.4.2.3 ! misho 2374: ** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred
! 2375: ** on the database connection D, then sqlite3_last_insert_rowid(D) returns
1.4.2.1 misho 2376: ** zero.
2377: **
2378: ** As well as being set automatically as rows are inserted into database
2379: ** tables, the value returned by this function may be set explicitly by
2380: ** [sqlite3_set_last_insert_rowid()]
2381: **
2382: ** Some virtual table implementations may INSERT rows into rowid tables as
2383: ** part of committing a transaction (e.g. to flush data accumulated in memory
2384: ** to disk). In this case subsequent calls to this function return the rowid
1.4.2.3 ! misho 2385: ** associated with these internal INSERT operations, which leads to
1.4.2.1 misho 2386: ** unintuitive results. Virtual table implementations that do write to rowid
1.4.2.3 ! misho 2387: ** tables in this way can avoid this problem by restoring the original
! 2388: ** rowid value using [sqlite3_set_last_insert_rowid()] before returning
1.4.2.1 misho 2389: ** control to the user.
2390: **
1.4.2.3 ! misho 2391: ** ^(If an [INSERT] occurs within a trigger then this routine will
! 2392: ** return the [rowid] of the inserted row as long as the trigger is
! 2393: ** running. Once the trigger program ends, the value returned
1.4.2.1 misho 2394: ** by this routine reverts to what it was before the trigger was fired.)^
1.2 misho 2395: **
2396: ** ^An [INSERT] that fails due to a constraint violation is not a
2397: ** successful [INSERT] and does not change the value returned by this
2398: ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
2399: ** and INSERT OR ABORT make no changes to the return value of this
2400: ** routine when their insertion fails. ^(When INSERT OR REPLACE
2401: ** encounters a constraint violation, it does not fail. The
2402: ** INSERT continues to completion after deleting rows that caused
2403: ** the constraint problem so INSERT OR REPLACE will always change
2404: ** the return value of this interface.)^
2405: **
2406: ** ^For the purposes of this routine, an [INSERT] is considered to
2407: ** be successful even if it is subsequently rolled back.
2408: **
2409: ** This function is accessible to SQL statements via the
2410: ** [last_insert_rowid() SQL function].
2411: **
2412: ** If a separate thread performs a new [INSERT] on the same
2413: ** database connection while the [sqlite3_last_insert_rowid()]
2414: ** function is running and thus changes the last insert [rowid],
2415: ** then the value returned by [sqlite3_last_insert_rowid()] is
2416: ** unpredictable and might not equal either the old or the new
2417: ** last insert [rowid].
2418: */
2419: SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
2420:
2421: /*
1.4.2.1 misho 2422: ** CAPI3REF: Set the Last Insert Rowid value.
2423: ** METHOD: sqlite3
2424: **
2425: ** The sqlite3_set_last_insert_rowid(D, R) method allows the application to
1.4.2.3 ! misho 2426: ** set the value returned by calling sqlite3_last_insert_rowid(D) to R
1.4.2.1 misho 2427: ** without inserting a row into the database.
2428: */
2429: SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64);
2430:
2431: /*
1.2 misho 2432: ** CAPI3REF: Count The Number Of Rows Modified
1.4 misho 2433: ** METHOD: sqlite3
1.2 misho 2434: **
1.4 misho 2435: ** ^This function returns the number of rows modified, inserted or
2436: ** deleted by the most recently completed INSERT, UPDATE or DELETE
2437: ** statement on the database connection specified by the only parameter.
2438: ** ^Executing any other type of SQL statement does not modify the value
2439: ** returned by this function.
2440: **
2441: ** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
1.4.2.3 ! misho 2442: ** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
1.4 misho 2443: ** [foreign key actions] or [REPLACE] constraint resolution are not counted.
1.4.2.3 ! misho 2444: **
! 2445: ** Changes to a view that are intercepted by
! 2446: ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
! 2447: ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
! 2448: ** DELETE statement run on a view is always zero. Only changes made to real
1.4 misho 2449: ** tables are counted.
2450: **
2451: ** Things are more complicated if the sqlite3_changes() function is
2452: ** executed while a trigger program is running. This may happen if the
2453: ** program uses the [changes() SQL function], or if some other callback
2454: ** function invokes sqlite3_changes() directly. Essentially:
1.4.2.3 ! misho 2455: **
1.4 misho 2456: ** <ul>
2457: ** <li> ^(Before entering a trigger program the value returned by
1.4.2.3 ! misho 2458: ** sqlite3_changes() function is saved. After the trigger program
1.4 misho 2459: ** has finished, the original value is restored.)^
1.4.2.3 ! misho 2460: **
! 2461: ** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE
! 2462: ** statement sets the value returned by sqlite3_changes()
! 2463: ** upon completion as normal. Of course, this value will not include
! 2464: ** any changes performed by sub-triggers, as the sqlite3_changes()
1.4 misho 2465: ** value will be saved and restored after each sub-trigger has run.)^
2466: ** </ul>
1.4.2.3 ! misho 2467: **
1.4 misho 2468: ** ^This means that if the changes() SQL function (or similar) is used
1.4.2.3 ! misho 2469: ** by the first INSERT, UPDATE or DELETE statement within a trigger, it
1.4 misho 2470: ** returns the value as set when the calling statement began executing.
1.4.2.3 ! misho 2471: ** ^If it is used by the second or subsequent such statement within a trigger
! 2472: ** program, the value returned reflects the number of rows modified by the
1.4 misho 2473: ** previous INSERT, UPDATE or DELETE statement within the same trigger.
1.2 misho 2474: **
2475: ** If a separate thread makes changes on the same database connection
2476: ** while [sqlite3_changes()] is running then the value returned
2477: ** is unpredictable and not meaningful.
1.4.2.2 misho 2478: **
2479: ** See also:
2480: ** <ul>
2481: ** <li> the [sqlite3_total_changes()] interface
2482: ** <li> the [count_changes pragma]
2483: ** <li> the [changes() SQL function]
2484: ** <li> the [data_version pragma]
2485: ** </ul>
1.2 misho 2486: */
2487: SQLITE_API int sqlite3_changes(sqlite3*);
2488:
2489: /*
2490: ** CAPI3REF: Total Number Of Rows Modified
1.4 misho 2491: ** METHOD: sqlite3
1.2 misho 2492: **
1.4 misho 2493: ** ^This function returns the total number of rows inserted, modified or
2494: ** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
2495: ** since the database connection was opened, including those executed as
2496: ** part of trigger programs. ^Executing any other type of SQL statement
2497: ** does not affect the value returned by sqlite3_total_changes().
1.4.2.3 ! misho 2498: **
1.4 misho 2499: ** ^Changes made as part of [foreign key actions] are included in the
2500: ** count, but those made as part of REPLACE constraint resolution are
1.4.2.3 ! misho 2501: ** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
1.4 misho 2502: ** are not counted.
1.2 misho 2503: **
1.4.2.2 misho 2504: ** The [sqlite3_total_changes(D)] interface only reports the number
2505: ** of rows that changed due to SQL statement run against database
2506: ** connection D. Any changes by other database connections are ignored.
2507: ** To detect changes against a database file from other database
2508: ** connections use the [PRAGMA data_version] command or the
2509: ** [SQLITE_FCNTL_DATA_VERSION] [file control].
1.4.2.3 ! misho 2510: **
1.2 misho 2511: ** If a separate thread makes changes on the same database connection
2512: ** while [sqlite3_total_changes()] is running then the value
2513: ** returned is unpredictable and not meaningful.
1.4.2.2 misho 2514: **
2515: ** See also:
2516: ** <ul>
2517: ** <li> the [sqlite3_changes()] interface
2518: ** <li> the [count_changes pragma]
2519: ** <li> the [changes() SQL function]
2520: ** <li> the [data_version pragma]
2521: ** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control]
2522: ** </ul>
1.2 misho 2523: */
2524: SQLITE_API int sqlite3_total_changes(sqlite3*);
2525:
2526: /*
2527: ** CAPI3REF: Interrupt A Long-Running Query
1.4 misho 2528: ** METHOD: sqlite3
1.2 misho 2529: **
2530: ** ^This function causes any pending database operation to abort and
2531: ** return at its earliest opportunity. This routine is typically
2532: ** called in response to a user action such as pressing "Cancel"
2533: ** or Ctrl-C where the user wants a long query operation to halt
2534: ** immediately.
2535: **
2536: ** ^It is safe to call this routine from a thread different from the
2537: ** thread that is currently running the database operation. But it
2538: ** is not safe to call this routine with a [database connection] that
2539: ** is closed or might close before sqlite3_interrupt() returns.
2540: **
2541: ** ^If an SQL operation is very nearly finished at the time when
2542: ** sqlite3_interrupt() is called, then it might not have an opportunity
2543: ** to be interrupted and might continue to completion.
2544: **
2545: ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
2546: ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
2547: ** that is inside an explicit transaction, then the entire transaction
2548: ** will be rolled back automatically.
2549: **
2550: ** ^The sqlite3_interrupt(D) call is in effect until all currently running
2551: ** SQL statements on [database connection] D complete. ^Any new SQL statements
1.4.2.3 ! misho 2552: ** that are started after the sqlite3_interrupt() call and before the
! 2553: ** running statement count reaches zero are interrupted as if they had been
1.2 misho 2554: ** running prior to the sqlite3_interrupt() call. ^New SQL statements
2555: ** that are started after the running statement count reaches zero are
2556: ** not effected by the sqlite3_interrupt().
2557: ** ^A call to sqlite3_interrupt(D) that occurs when there are no running
2558: ** SQL statements is a no-op and has no effect on SQL statements
2559: ** that are started after the sqlite3_interrupt() call returns.
2560: */
2561: SQLITE_API void sqlite3_interrupt(sqlite3*);
2562:
2563: /*
2564: ** CAPI3REF: Determine If An SQL Statement Is Complete
2565: **
2566: ** These routines are useful during command-line input to determine if the
2567: ** currently entered text seems to form a complete SQL statement or
2568: ** if additional input is needed before sending the text into
2569: ** SQLite for parsing. ^These routines return 1 if the input string
2570: ** appears to be a complete SQL statement. ^A statement is judged to be
2571: ** complete if it ends with a semicolon token and is not a prefix of a
2572: ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
2573: ** string literals or quoted identifier names or comments are not
2574: ** independent tokens (they are part of the token in which they are
2575: ** embedded) and thus do not count as a statement terminator. ^Whitespace
2576: ** and comments that follow the final semicolon are ignored.
2577: **
2578: ** ^These routines return 0 if the statement is incomplete. ^If a
2579: ** memory allocation fails, then SQLITE_NOMEM is returned.
2580: **
2581: ** ^These routines do not parse the SQL statements thus
2582: ** will not detect syntactically incorrect SQL.
2583: **
1.4.2.3 ! misho 2584: ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
1.2 misho 2585: ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
2586: ** automatically by sqlite3_complete16(). If that initialization fails,
2587: ** then the return value from sqlite3_complete16() will be non-zero
2588: ** regardless of whether or not the input SQL is complete.)^
2589: **
2590: ** The input to [sqlite3_complete()] must be a zero-terminated
2591: ** UTF-8 string.
2592: **
2593: ** The input to [sqlite3_complete16()] must be a zero-terminated
2594: ** UTF-16 string in native byte order.
2595: */
2596: SQLITE_API int sqlite3_complete(const char *sql);
2597: SQLITE_API int sqlite3_complete16(const void *sql);
2598:
2599: /*
2600: ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
1.4 misho 2601: ** KEYWORDS: {busy-handler callback} {busy handler}
2602: ** METHOD: sqlite3
1.2 misho 2603: **
1.4 misho 2604: ** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
2605: ** that might be invoked with argument P whenever
2606: ** an attempt is made to access a database table associated with
2607: ** [database connection] D when another thread
2608: ** or process has the table locked.
2609: ** The sqlite3_busy_handler() interface is used to implement
2610: ** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
1.2 misho 2611: **
1.4 misho 2612: ** ^If the busy callback is NULL, then [SQLITE_BUSY]
1.2 misho 2613: ** is returned immediately upon encountering the lock. ^If the busy callback
2614: ** is not NULL, then the callback might be invoked with two arguments.
2615: **
2616: ** ^The first argument to the busy handler is a copy of the void* pointer which
2617: ** is the third argument to sqlite3_busy_handler(). ^The second argument to
2618: ** the busy handler callback is the number of times that the busy handler has
1.4 misho 2619: ** been invoked previously for the same locking event. ^If the
1.2 misho 2620: ** busy callback returns 0, then no additional attempts are made to
1.4 misho 2621: ** access the database and [SQLITE_BUSY] is returned
2622: ** to the application.
1.2 misho 2623: ** ^If the callback returns non-zero, then another attempt
1.4 misho 2624: ** is made to access the database and the cycle repeats.
1.2 misho 2625: **
2626: ** The presence of a busy handler does not guarantee that it will be invoked
2627: ** when there is lock contention. ^If SQLite determines that invoking the busy
2628: ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
1.4.2.3 ! misho 2629: ** to the application instead of invoking the
1.4 misho 2630: ** busy handler.
1.2 misho 2631: ** Consider a scenario where one process is holding a read lock that
2632: ** it is trying to promote to a reserved lock and
2633: ** a second process is holding a reserved lock that it is trying
2634: ** to promote to an exclusive lock. The first process cannot proceed
2635: ** because it is blocked by the second and the second process cannot
2636: ** proceed because it is blocked by the first. If both processes
2637: ** invoke the busy handlers, neither will make any progress. Therefore,
2638: ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
2639: ** will induce the first process to release its read lock and allow
2640: ** the second process to proceed.
2641: **
2642: ** ^The default busy callback is NULL.
2643: **
2644: ** ^(There can only be a single busy handler defined for each
2645: ** [database connection]. Setting a new busy handler clears any
2646: ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
1.4 misho 2647: ** or evaluating [PRAGMA busy_timeout=N] will change the
2648: ** busy handler and thus clear any previously set busy handler.
1.2 misho 2649: **
2650: ** The busy callback should not take any actions which modify the
1.4 misho 2651: ** database connection that invoked the busy handler. In other words,
2652: ** the busy handler is not reentrant. Any such actions
1.2 misho 2653: ** result in undefined behavior.
1.4.2.3 ! misho 2654: **
1.2 misho 2655: ** A busy handler must not close the database connection
2656: ** or [prepared statement] that invoked the busy handler.
2657: */
1.4 misho 2658: SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);
1.2 misho 2659:
2660: /*
2661: ** CAPI3REF: Set A Busy Timeout
1.4 misho 2662: ** METHOD: sqlite3
1.2 misho 2663: **
2664: ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
2665: ** for a specified amount of time when a table is locked. ^The handler
2666: ** will sleep multiple times until at least "ms" milliseconds of sleeping
2667: ** have accumulated. ^After at least "ms" milliseconds of sleeping,
2668: ** the handler returns 0 which causes [sqlite3_step()] to return
1.4 misho 2669: ** [SQLITE_BUSY].
1.2 misho 2670: **
2671: ** ^Calling this routine with an argument less than or equal to zero
2672: ** turns off all busy handlers.
2673: **
2674: ** ^(There can only be a single busy handler for a particular
1.4 misho 2675: ** [database connection] at any given moment. If another busy handler
1.2 misho 2676: ** was defined (using [sqlite3_busy_handler()]) prior to calling
2677: ** this routine, that other busy handler is cleared.)^
1.4 misho 2678: **
2679: ** See also: [PRAGMA busy_timeout]
1.2 misho 2680: */
2681: SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
2682:
2683: /*
2684: ** CAPI3REF: Convenience Routines For Running Queries
1.4 misho 2685: ** METHOD: sqlite3
1.2 misho 2686: **
2687: ** This is a legacy interface that is preserved for backwards compatibility.
2688: ** Use of this interface is not recommended.
2689: **
2690: ** Definition: A <b>result table</b> is memory data structure created by the
2691: ** [sqlite3_get_table()] interface. A result table records the
2692: ** complete query results from one or more queries.
2693: **
2694: ** The table conceptually has a number of rows and columns. But
2695: ** these numbers are not part of the result table itself. These
2696: ** numbers are obtained separately. Let N be the number of rows
2697: ** and M be the number of columns.
2698: **
2699: ** A result table is an array of pointers to zero-terminated UTF-8 strings.
2700: ** There are (N+1)*M elements in the array. The first M pointers point
2701: ** to zero-terminated strings that contain the names of the columns.
2702: ** The remaining entries all point to query results. NULL values result
2703: ** in NULL pointers. All other values are in their UTF-8 zero-terminated
2704: ** string representation as returned by [sqlite3_column_text()].
2705: **
2706: ** A result table might consist of one or more memory allocations.
2707: ** It is not safe to pass a result table directly to [sqlite3_free()].
2708: ** A result table should be deallocated using [sqlite3_free_table()].
2709: **
2710: ** ^(As an example of the result table format, suppose a query result
2711: ** is as follows:
2712: **
2713: ** <blockquote><pre>
2714: ** Name | Age
2715: ** -----------------------
2716: ** Alice | 43
2717: ** Bob | 28
2718: ** Cindy | 21
2719: ** </pre></blockquote>
2720: **
1.4.2.3 ! misho 2721: ** There are two columns (M==2) and three rows (N==3). Thus the
1.2 misho 2722: ** result table has 8 entries. Suppose the result table is stored
1.4.2.3 ! misho 2723: ** in an array named azResult. Then azResult holds this content:
1.2 misho 2724: **
2725: ** <blockquote><pre>
2726: ** azResult[0] = "Name";
2727: ** azResult[1] = "Age";
2728: ** azResult[2] = "Alice";
2729: ** azResult[3] = "43";
2730: ** azResult[4] = "Bob";
2731: ** azResult[5] = "28";
2732: ** azResult[6] = "Cindy";
2733: ** azResult[7] = "21";
2734: ** </pre></blockquote>)^
2735: **
2736: ** ^The sqlite3_get_table() function evaluates one or more
2737: ** semicolon-separated SQL statements in the zero-terminated UTF-8
2738: ** string of its 2nd parameter and returns a result table to the
2739: ** pointer given in its 3rd parameter.
2740: **
2741: ** After the application has finished with the result from sqlite3_get_table(),
2742: ** it must pass the result table pointer to sqlite3_free_table() in order to
2743: ** release the memory that was malloced. Because of the way the
2744: ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
2745: ** function must not try to call [sqlite3_free()] directly. Only
2746: ** [sqlite3_free_table()] is able to release the memory properly and safely.
2747: **
2748: ** The sqlite3_get_table() interface is implemented as a wrapper around
2749: ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
2750: ** to any internal data structures of SQLite. It uses only the public
2751: ** interface defined here. As a consequence, errors that occur in the
2752: ** wrapper layer outside of the internal [sqlite3_exec()] call are not
2753: ** reflected in subsequent calls to [sqlite3_errcode()] or
2754: ** [sqlite3_errmsg()].
2755: */
2756: SQLITE_API int sqlite3_get_table(
2757: sqlite3 *db, /* An open database */
2758: const char *zSql, /* SQL to be evaluated */
2759: char ***pazResult, /* Results of the query */
2760: int *pnRow, /* Number of result rows written here */
2761: int *pnColumn, /* Number of result columns written here */
2762: char **pzErrmsg /* Error msg written here */
2763: );
2764: SQLITE_API void sqlite3_free_table(char **result);
2765:
2766: /*
2767: ** CAPI3REF: Formatted String Printing Functions
2768: **
2769: ** These routines are work-alikes of the "printf()" family of functions
2770: ** from the standard C library.
1.4.2.2 misho 2771: ** These routines understand most of the common formatting options from
1.4.2.3 ! misho 2772: ** the standard library printf()
1.4.2.2 misho 2773: ** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]).
2774: ** See the [built-in printf()] documentation for details.
1.2 misho 2775: **
2776: ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
1.4.2.2 misho 2777: ** results into memory obtained from [sqlite3_malloc64()].
1.2 misho 2778: ** The strings returned by these two routines should be
2779: ** released by [sqlite3_free()]. ^Both routines return a
1.4.2.2 misho 2780: ** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough
1.2 misho 2781: ** memory to hold the resulting string.
2782: **
2783: ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
2784: ** the standard C library. The result is written into the
2785: ** buffer supplied as the second parameter whose size is given by
2786: ** the first parameter. Note that the order of the
2787: ** first two parameters is reversed from snprintf().)^ This is an
2788: ** historical accident that cannot be fixed without breaking
2789: ** backwards compatibility. ^(Note also that sqlite3_snprintf()
2790: ** returns a pointer to its buffer instead of the number of
2791: ** characters actually written into the buffer.)^ We admit that
2792: ** the number of characters written would be a more useful return
2793: ** value but we cannot change the implementation of sqlite3_snprintf()
2794: ** now without breaking compatibility.
2795: **
2796: ** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
2797: ** guarantees that the buffer is always zero-terminated. ^The first
2798: ** parameter "n" is the total size of the buffer, including space for
2799: ** the zero terminator. So the longest string that can be completely
2800: ** written will be n-1 characters.
2801: **
2802: ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
2803: **
1.4.2.2 misho 2804: ** See also: [built-in printf()], [printf() SQL function]
1.2 misho 2805: */
2806: SQLITE_API char *sqlite3_mprintf(const char*,...);
2807: SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
2808: SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
2809: SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
2810:
2811: /*
2812: ** CAPI3REF: Memory Allocation Subsystem
2813: **
2814: ** The SQLite core uses these three routines for all of its own
2815: ** internal memory allocation needs. "Core" in the previous sentence
1.4.2.3 ! misho 2816: ** does not include operating-system specific [VFS] implementation. The
1.2 misho 2817: ** Windows VFS uses native malloc() and free() for some operations.
2818: **
2819: ** ^The sqlite3_malloc() routine returns a pointer to a block
2820: ** of memory at least N bytes in length, where N is the parameter.
2821: ** ^If sqlite3_malloc() is unable to obtain sufficient free
2822: ** memory, it returns a NULL pointer. ^If the parameter N to
2823: ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
2824: ** a NULL pointer.
2825: **
1.4 misho 2826: ** ^The sqlite3_malloc64(N) routine works just like
2827: ** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
2828: ** of a signed 32-bit integer.
2829: **
1.2 misho 2830: ** ^Calling sqlite3_free() with a pointer previously returned
2831: ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
2832: ** that it might be reused. ^The sqlite3_free() routine is
2833: ** a no-op if is called with a NULL pointer. Passing a NULL pointer
2834: ** to sqlite3_free() is harmless. After being freed, memory
2835: ** should neither be read nor written. Even reading previously freed
2836: ** memory might result in a segmentation fault or other severe error.
2837: ** Memory corruption, a segmentation fault, or other severe error
2838: ** might result if sqlite3_free() is called with a non-NULL pointer that
2839: ** was not obtained from sqlite3_malloc() or sqlite3_realloc().
2840: **
1.4 misho 2841: ** ^The sqlite3_realloc(X,N) interface attempts to resize a
2842: ** prior memory allocation X to be at least N bytes.
2843: ** ^If the X parameter to sqlite3_realloc(X,N)
1.2 misho 2844: ** is a NULL pointer then its behavior is identical to calling
1.4 misho 2845: ** sqlite3_malloc(N).
2846: ** ^If the N parameter to sqlite3_realloc(X,N) is zero or
1.2 misho 2847: ** negative then the behavior is exactly the same as calling
1.4 misho 2848: ** sqlite3_free(X).
2849: ** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
2850: ** of at least N bytes in size or NULL if insufficient memory is available.
1.2 misho 2851: ** ^If M is the size of the prior allocation, then min(N,M) bytes
2852: ** of the prior allocation are copied into the beginning of buffer returned
1.4 misho 2853: ** by sqlite3_realloc(X,N) and the prior allocation is freed.
2854: ** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
2855: ** prior allocation is not freed.
2856: **
2857: ** ^The sqlite3_realloc64(X,N) interfaces works the same as
2858: ** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
2859: ** of a 32-bit signed integer.
2860: **
2861: ** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
2862: ** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
2863: ** sqlite3_msize(X) returns the size of that memory allocation in bytes.
2864: ** ^The value returned by sqlite3_msize(X) might be larger than the number
2865: ** of bytes requested when X was allocated. ^If X is a NULL pointer then
2866: ** sqlite3_msize(X) returns zero. If X points to something that is not
2867: ** the beginning of memory allocation, or if it points to a formerly
2868: ** valid memory allocation that has now been freed, then the behavior
2869: ** of sqlite3_msize(X) is undefined and possibly harmful.
1.2 misho 2870: **
1.4 misho 2871: ** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
2872: ** sqlite3_malloc64(), and sqlite3_realloc64()
1.2 misho 2873: ** is always aligned to at least an 8 byte boundary, or to a
2874: ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
2875: ** option is used.
2876: **
2877: ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
2878: ** must be either NULL or else pointers obtained from a prior
2879: ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
2880: ** not yet been released.
2881: **
2882: ** The application must not read or write any part of
2883: ** a block of memory after it has been released using
2884: ** [sqlite3_free()] or [sqlite3_realloc()].
2885: */
2886: SQLITE_API void *sqlite3_malloc(int);
1.4 misho 2887: SQLITE_API void *sqlite3_malloc64(sqlite3_uint64);
1.2 misho 2888: SQLITE_API void *sqlite3_realloc(void*, int);
1.4 misho 2889: SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64);
1.2 misho 2890: SQLITE_API void sqlite3_free(void*);
1.4 misho 2891: SQLITE_API sqlite3_uint64 sqlite3_msize(void*);
1.2 misho 2892:
2893: /*
2894: ** CAPI3REF: Memory Allocator Statistics
2895: **
2896: ** SQLite provides these two interfaces for reporting on the status
2897: ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
2898: ** routines, which form the built-in memory allocation subsystem.
2899: **
2900: ** ^The [sqlite3_memory_used()] routine returns the number of bytes
2901: ** of memory currently outstanding (malloced but not freed).
2902: ** ^The [sqlite3_memory_highwater()] routine returns the maximum
2903: ** value of [sqlite3_memory_used()] since the high-water mark
2904: ** was last reset. ^The values returned by [sqlite3_memory_used()] and
2905: ** [sqlite3_memory_highwater()] include any overhead
2906: ** added by SQLite in its implementation of [sqlite3_malloc()],
2907: ** but not overhead added by the any underlying system library
2908: ** routines that [sqlite3_malloc()] may call.
2909: **
2910: ** ^The memory high-water mark is reset to the current value of
2911: ** [sqlite3_memory_used()] if and only if the parameter to
2912: ** [sqlite3_memory_highwater()] is true. ^The value returned
2913: ** by [sqlite3_memory_highwater(1)] is the high-water mark
2914: ** prior to the reset.
2915: */
2916: SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
2917: SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
2918:
2919: /*
2920: ** CAPI3REF: Pseudo-Random Number Generator
2921: **
2922: ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
2923: ** select random [ROWID | ROWIDs] when inserting new records into a table that
2924: ** already uses the largest possible [ROWID]. The PRNG is also used for
1.4.2.3 ! misho 2925: ** the built-in random() and randomblob() SQL functions. This interface allows
1.2 misho 2926: ** applications to access the same PRNG for other purposes.
2927: **
2928: ** ^A call to this routine stores N bytes of randomness into buffer P.
1.4 misho 2929: ** ^The P parameter can be a NULL pointer.
1.2 misho 2930: **
1.4 misho 2931: ** ^If this routine has not been previously called or if the previous
2932: ** call had N less than one or a NULL pointer for P, then the PRNG is
2933: ** seeded using randomness obtained from the xRandomness method of
2934: ** the default [sqlite3_vfs] object.
2935: ** ^If the previous call to this routine had an N of 1 or more and a
2936: ** non-NULL P then the pseudo-randomness is generated
1.2 misho 2937: ** internally and without recourse to the [sqlite3_vfs] xRandomness
2938: ** method.
2939: */
2940: SQLITE_API void sqlite3_randomness(int N, void *P);
2941:
2942: /*
2943: ** CAPI3REF: Compile-Time Authorization Callbacks
1.4 misho 2944: ** METHOD: sqlite3
1.4.2.1 misho 2945: ** KEYWORDS: {authorizer callback}
1.2 misho 2946: **
2947: ** ^This routine registers an authorizer callback with a particular
2948: ** [database connection], supplied in the first argument.
2949: ** ^The authorizer callback is invoked as SQL statements are being compiled
2950: ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
1.4.2.2 misho 2951: ** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()],
2952: ** and [sqlite3_prepare16_v3()]. ^At various
1.2 misho 2953: ** points during the compilation process, as logic is being created
2954: ** to perform various actions, the authorizer callback is invoked to
2955: ** see if those actions are allowed. ^The authorizer callback should
2956: ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
2957: ** specific action but allow the SQL statement to continue to be
2958: ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
2959: ** rejected with an error. ^If the authorizer callback returns
2960: ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
2961: ** then the [sqlite3_prepare_v2()] or equivalent call that triggered
2962: ** the authorizer will fail with an error message.
2963: **
2964: ** When the callback returns [SQLITE_OK], that means the operation
2965: ** requested is ok. ^When the callback returns [SQLITE_DENY], the
2966: ** [sqlite3_prepare_v2()] or equivalent call that triggered the
2967: ** authorizer will fail with an error message explaining that
1.4.2.3 ! misho 2968: ** access is denied.
1.2 misho 2969: **
2970: ** ^The first parameter to the authorizer callback is a copy of the third
2971: ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
2972: ** to the callback is an integer [SQLITE_COPY | action code] that specifies
2973: ** the particular action to be authorized. ^The third through sixth parameters
1.4.2.1 misho 2974: ** to the callback are either NULL pointers or zero-terminated strings
2975: ** that contain additional details about the action to be authorized.
2976: ** Applications must always be prepared to encounter a NULL pointer in any
2977: ** of the third through the sixth parameters of the authorization callback.
1.2 misho 2978: **
2979: ** ^If the action code is [SQLITE_READ]
2980: ** and the callback returns [SQLITE_IGNORE] then the
2981: ** [prepared statement] statement is constructed to substitute
2982: ** a NULL value in place of the table column that would have
2983: ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
2984: ** return can be used to deny an untrusted user access to individual
2985: ** columns of a table.
1.4.2.1 misho 2986: ** ^When a table is referenced by a [SELECT] but no column values are
2987: ** extracted from that table (for example in a query like
2988: ** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback
2989: ** is invoked once for that table with a column name that is an empty string.
1.2 misho 2990: ** ^If the action code is [SQLITE_DELETE] and the callback returns
2991: ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
2992: ** [truncate optimization] is disabled and all rows are deleted individually.
2993: **
2994: ** An authorizer is used when [sqlite3_prepare | preparing]
2995: ** SQL statements from an untrusted source, to ensure that the SQL statements
2996: ** do not try to access data they are not allowed to see, or that they do not
2997: ** try to execute malicious statements that damage the database. For
2998: ** example, an application may allow a user to enter arbitrary
2999: ** SQL queries for evaluation by a database. But the application does
3000: ** not want the user to be able to make arbitrary changes to the
3001: ** database. An authorizer could then be put in place while the
3002: ** user-entered SQL is being [sqlite3_prepare | prepared] that
3003: ** disallows everything except [SELECT] statements.
3004: **
3005: ** Applications that need to process SQL from untrusted sources
3006: ** might also consider lowering resource limits using [sqlite3_limit()]
3007: ** and limiting database size using the [max_page_count] [PRAGMA]
3008: ** in addition to using an authorizer.
3009: **
3010: ** ^(Only a single authorizer can be in place on a database connection
3011: ** at a time. Each call to sqlite3_set_authorizer overrides the
3012: ** previous call.)^ ^Disable the authorizer by installing a NULL callback.
3013: ** The authorizer is disabled by default.
3014: **
3015: ** The authorizer callback must not do anything that will modify
3016: ** the database connection that invoked the authorizer callback.
3017: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3018: ** database connections for the meaning of "modify" in this paragraph.
3019: **
3020: ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
1.4.2.3 ! misho 3021: ** statement might be re-prepared during [sqlite3_step()] due to a
1.2 misho 3022: ** schema change. Hence, the application should ensure that the
3023: ** correct authorizer callback remains in place during the [sqlite3_step()].
3024: **
3025: ** ^Note that the authorizer callback is invoked only during
3026: ** [sqlite3_prepare()] or its variants. Authorization is not
3027: ** performed during statement evaluation in [sqlite3_step()], unless
3028: ** as stated in the previous paragraph, sqlite3_step() invokes
3029: ** sqlite3_prepare_v2() to reprepare a statement after a schema change.
3030: */
3031: SQLITE_API int sqlite3_set_authorizer(
3032: sqlite3*,
3033: int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
3034: void *pUserData
3035: );
3036:
3037: /*
3038: ** CAPI3REF: Authorizer Return Codes
3039: **
3040: ** The [sqlite3_set_authorizer | authorizer callback function] must
3041: ** return either [SQLITE_OK] or one of these two constants in order
3042: ** to signal SQLite whether or not the action is permitted. See the
3043: ** [sqlite3_set_authorizer | authorizer documentation] for additional
3044: ** information.
3045: **
1.4 misho 3046: ** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
3047: ** returned from the [sqlite3_vtab_on_conflict()] interface.
1.2 misho 3048: */
3049: #define SQLITE_DENY 1 /* Abort the SQL statement with an error */
3050: #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
3051:
3052: /*
3053: ** CAPI3REF: Authorizer Action Codes
3054: **
3055: ** The [sqlite3_set_authorizer()] interface registers a callback function
3056: ** that is invoked to authorize certain SQL statement actions. The
3057: ** second parameter to the callback is an integer code that specifies
3058: ** what action is being authorized. These are the integer action codes that
3059: ** the authorizer callback may be passed.
3060: **
3061: ** These action code values signify what kind of operation is to be
3062: ** authorized. The 3rd and 4th parameters to the authorization
3063: ** callback function will be parameters or NULL depending on which of these
3064: ** codes is used as the second parameter. ^(The 5th parameter to the
3065: ** authorizer callback is the name of the database ("main", "temp",
3066: ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
3067: ** is the name of the inner-most trigger or view that is responsible for
3068: ** the access attempt or NULL if this access attempt is directly from
3069: ** top-level SQL code.
3070: */
3071: /******************************************* 3rd ************ 4th ***********/
3072: #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
3073: #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
3074: #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
3075: #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
3076: #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
3077: #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
3078: #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
3079: #define SQLITE_CREATE_VIEW 8 /* View Name NULL */
3080: #define SQLITE_DELETE 9 /* Table Name NULL */
3081: #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
3082: #define SQLITE_DROP_TABLE 11 /* Table Name NULL */
3083: #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
3084: #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
3085: #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
3086: #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
3087: #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
3088: #define SQLITE_DROP_VIEW 17 /* View Name NULL */
3089: #define SQLITE_INSERT 18 /* Table Name NULL */
3090: #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
3091: #define SQLITE_READ 20 /* Table Name Column Name */
3092: #define SQLITE_SELECT 21 /* NULL NULL */
3093: #define SQLITE_TRANSACTION 22 /* Operation NULL */
3094: #define SQLITE_UPDATE 23 /* Table Name Column Name */
3095: #define SQLITE_ATTACH 24 /* Filename NULL */
3096: #define SQLITE_DETACH 25 /* Database Name NULL */
3097: #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
3098: #define SQLITE_REINDEX 27 /* Index Name NULL */
3099: #define SQLITE_ANALYZE 28 /* Table Name NULL */
3100: #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
3101: #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
3102: #define SQLITE_FUNCTION 31 /* NULL Function Name */
3103: #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
3104: #define SQLITE_COPY 0 /* No longer used */
1.4 misho 3105: #define SQLITE_RECURSIVE 33 /* NULL NULL */
1.2 misho 3106:
3107: /*
3108: ** CAPI3REF: Tracing And Profiling Functions
1.4 misho 3109: ** METHOD: sqlite3
3110: **
3111: ** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
3112: ** instead of the routines described here.
1.2 misho 3113: **
3114: ** These routines register callback functions that can be used for
3115: ** tracing and profiling the execution of SQL statements.
3116: **
3117: ** ^The callback function registered by sqlite3_trace() is invoked at
3118: ** various times when an SQL statement is being run by [sqlite3_step()].
3119: ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
3120: ** SQL statement text as the statement first begins executing.
3121: ** ^(Additional sqlite3_trace() callbacks might occur
3122: ** as each triggered subprogram is entered. The callbacks for triggers
3123: ** contain a UTF-8 SQL comment that identifies the trigger.)^
3124: **
1.4 misho 3125: ** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
3126: ** the length of [bound parameter] expansion in the output of sqlite3_trace().
3127: **
1.2 misho 3128: ** ^The callback function registered by sqlite3_profile() is invoked
3129: ** as each SQL statement finishes. ^The profile callback contains
3130: ** the original statement text and an estimate of wall-clock time
3131: ** of how long that statement took to run. ^The profile callback
3132: ** time is in units of nanoseconds, however the current implementation
3133: ** is only capable of millisecond resolution so the six least significant
3134: ** digits in the time are meaningless. Future versions of SQLite
1.4.2.2 misho 3135: ** might provide greater resolution on the profiler callback. Invoking
3136: ** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the
3137: ** profile callback.
1.2 misho 3138: */
1.4 misho 3139: SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*,
3140: void(*xTrace)(void*,const char*), void*);
3141: SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*,
1.2 misho 3142: void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
3143:
3144: /*
1.4 misho 3145: ** CAPI3REF: SQL Trace Event Codes
3146: ** KEYWORDS: SQLITE_TRACE
3147: **
3148: ** These constants identify classes of events that can be monitored
1.4.2.2 misho 3149: ** using the [sqlite3_trace_v2()] tracing logic. The M argument
3150: ** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of
1.4 misho 3151: ** the following constants. ^The first argument to the trace callback
3152: ** is one of the following constants.
3153: **
3154: ** New tracing constants may be added in future releases.
3155: **
3156: ** ^A trace callback has four arguments: xCallback(T,C,P,X).
3157: ** ^The T argument is one of the integer type codes above.
3158: ** ^The C argument is a copy of the context pointer passed in as the
3159: ** fourth argument to [sqlite3_trace_v2()].
3160: ** The P and X arguments are pointers whose meanings depend on T.
3161: **
3162: ** <dl>
3163: ** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>
3164: ** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
3165: ** first begins running and possibly at other times during the
3166: ** execution of the prepared statement, such as at the start of each
3167: ** trigger subprogram. ^The P argument is a pointer to the
3168: ** [prepared statement]. ^The X argument is a pointer to a string which
1.4.2.3 ! misho 3169: ** is the unexpanded SQL text of the prepared statement or an SQL comment
1.4 misho 3170: ** that indicates the invocation of a trigger. ^The callback can compute
3171: ** the same text that would have been returned by the legacy [sqlite3_trace()]
3172: ** interface by using the X argument when X begins with "--" and invoking
3173: ** [sqlite3_expanded_sql(P)] otherwise.
3174: **
3175: ** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
3176: ** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
3177: ** information as is provided by the [sqlite3_profile()] callback.
3178: ** ^The P argument is a pointer to the [prepared statement] and the
3179: ** X argument points to a 64-bit integer which is the estimated of
3180: ** the number of nanosecond that the prepared statement took to run.
3181: ** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
3182: **
3183: ** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
3184: ** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
1.4.2.3 ! misho 3185: ** statement generates a single row of result.
1.4 misho 3186: ** ^The P argument is a pointer to the [prepared statement] and the
3187: ** X argument is unused.
3188: **
3189: ** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>
3190: ** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database
3191: ** connection closes.
3192: ** ^The P argument is a pointer to the [database connection] object
3193: ** and the X argument is unused.
3194: ** </dl>
3195: */
3196: #define SQLITE_TRACE_STMT 0x01
3197: #define SQLITE_TRACE_PROFILE 0x02
3198: #define SQLITE_TRACE_ROW 0x04
3199: #define SQLITE_TRACE_CLOSE 0x08
3200:
3201: /*
3202: ** CAPI3REF: SQL Trace Hook
3203: ** METHOD: sqlite3
3204: **
3205: ** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
3206: ** function X against [database connection] D, using property mask M
3207: ** and context pointer P. ^If the X callback is
3208: ** NULL or if the M mask is zero, then tracing is disabled. The
3209: ** M argument should be the bitwise OR-ed combination of
3210: ** zero or more [SQLITE_TRACE] constants.
3211: **
1.4.2.3 ! misho 3212: ** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides
1.4 misho 3213: ** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2().
3214: **
1.4.2.3 ! misho 3215: ** ^The X callback is invoked whenever any of the events identified by
1.4 misho 3216: ** mask M occur. ^The integer return value from the callback is currently
3217: ** ignored, though this may change in future releases. Callback
3218: ** implementations should return zero to ensure future compatibility.
3219: **
3220: ** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
3221: ** ^The T argument is one of the [SQLITE_TRACE]
3222: ** constants to indicate why the callback was invoked.
3223: ** ^The C argument is a copy of the context pointer.
3224: ** The P and X arguments are pointers whose meanings depend on T.
3225: **
3226: ** The sqlite3_trace_v2() interface is intended to replace the legacy
3227: ** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
3228: ** are deprecated.
3229: */
3230: SQLITE_API int sqlite3_trace_v2(
3231: sqlite3*,
3232: unsigned uMask,
3233: int(*xCallback)(unsigned,void*,void*,void*),
3234: void *pCtx
3235: );
3236:
3237: /*
1.2 misho 3238: ** CAPI3REF: Query Progress Callbacks
1.4 misho 3239: ** METHOD: sqlite3
1.2 misho 3240: **
3241: ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
3242: ** function X to be invoked periodically during long running calls to
3243: ** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
3244: ** database connection D. An example use for this
3245: ** interface is to keep a GUI updated during a large query.
3246: **
1.4.2.3 ! misho 3247: ** ^The parameter P is passed through as the only parameter to the
! 3248: ** callback function X. ^The parameter N is the approximate number of
1.2 misho 3249: ** [virtual machine instructions] that are evaluated between successive
1.4 misho 3250: ** invocations of the callback X. ^If N is less than one then the progress
3251: ** handler is disabled.
1.2 misho 3252: **
3253: ** ^Only a single progress handler may be defined at one time per
3254: ** [database connection]; setting a new progress handler cancels the
3255: ** old one. ^Setting parameter X to NULL disables the progress handler.
3256: ** ^The progress handler is also disabled by setting N to a value less
3257: ** than 1.
3258: **
3259: ** ^If the progress callback returns non-zero, the operation is
3260: ** interrupted. This feature can be used to implement a
3261: ** "Cancel" button on a GUI progress dialog box.
3262: **
3263: ** The progress handler callback must not do anything that will modify
3264: ** the database connection that invoked the progress handler.
3265: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3266: ** database connections for the meaning of "modify" in this paragraph.
3267: **
3268: */
3269: SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
3270:
3271: /*
3272: ** CAPI3REF: Opening A New Database Connection
1.4 misho 3273: ** CONSTRUCTOR: sqlite3
1.2 misho 3274: **
1.4.2.3 ! misho 3275: ** ^These routines open an SQLite database file as specified by the
1.2 misho 3276: ** filename argument. ^The filename argument is interpreted as UTF-8 for
3277: ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
3278: ** order for sqlite3_open16(). ^(A [database connection] handle is usually
3279: ** returned in *ppDb, even if an error occurs. The only exception is that
3280: ** if SQLite is unable to allocate memory to hold the [sqlite3] object,
3281: ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
3282: ** object.)^ ^(If the database is opened (and/or created) successfully, then
3283: ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
3284: ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
3285: ** an English language description of the error following a failure of any
3286: ** of the sqlite3_open() routines.
3287: **
1.4 misho 3288: ** ^The default encoding will be UTF-8 for databases created using
3289: ** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases
3290: ** created using sqlite3_open16() will be UTF-16 in the native byte order.
1.2 misho 3291: **
3292: ** Whether or not an error occurs when it is opened, resources
3293: ** associated with the [database connection] handle should be released by
3294: ** passing it to [sqlite3_close()] when it is no longer required.
3295: **
3296: ** The sqlite3_open_v2() interface works like sqlite3_open()
3297: ** except that it accepts two additional parameters for additional control
3298: ** over the new database connection. ^(The flags parameter to
1.4.2.3 ! misho 3299: ** sqlite3_open_v2() must include, at a minimum, one of the following
! 3300: ** three flag combinations:)^
1.2 misho 3301: **
3302: ** <dl>
3303: ** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
3304: ** <dd>The database is opened in read-only mode. If the database does not
3305: ** already exist, an error is returned.</dd>)^
3306: **
3307: ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
3308: ** <dd>The database is opened for reading and writing if possible, or reading
3309: ** only if the file is write protected by the operating system. In either
3310: ** case the database must already exist, otherwise an error is returned.</dd>)^
3311: **
3312: ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
3313: ** <dd>The database is opened for reading and writing, and is created if
3314: ** it does not already exist. This is the behavior that is always used for
3315: ** sqlite3_open() and sqlite3_open16().</dd>)^
3316: ** </dl>
3317: **
1.4.2.3 ! misho 3318: ** In addition to the required flags, the following optional flags are
! 3319: ** also supported:
! 3320: **
! 3321: ** <dl>
! 3322: ** ^(<dt>[SQLITE_OPEN_URI]</dt>
! 3323: ** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^
! 3324: **
! 3325: ** ^(<dt>[SQLITE_OPEN_MEMORY]</dt>
! 3326: ** <dd>The database will be opened as an in-memory database. The database
! 3327: ** is named by the "filename" argument for the purposes of cache-sharing,
! 3328: ** if shared cache mode is enabled, but the "filename" is otherwise ignored.
! 3329: ** </dd>)^
! 3330: **
! 3331: ** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt>
! 3332: ** <dd>The new database connection will use the "multi-thread"
! 3333: ** [threading mode].)^ This means that separate threads are allowed
! 3334: ** to use SQLite at the same time, as long as each thread is using
! 3335: ** a different [database connection].
! 3336: **
! 3337: ** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt>
! 3338: ** <dd>The new database connection will use the "serialized"
! 3339: ** [threading mode].)^ This means the multiple threads can safely
! 3340: ** attempt to use the same database connection at the same time.
! 3341: ** (Mutexes will block any actual concurrency, but in this mode
! 3342: ** there is no harm in trying.)
! 3343: **
! 3344: ** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt>
! 3345: ** <dd>The database is opened [shared cache] enabled, overriding
! 3346: ** the default shared cache setting provided by
! 3347: ** [sqlite3_enable_shared_cache()].)^
! 3348: **
! 3349: ** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt>
! 3350: ** <dd>The database is opened [shared cache] disabled, overriding
! 3351: ** the default shared cache setting provided by
! 3352: ** [sqlite3_enable_shared_cache()].)^
! 3353: **
! 3354: ** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt>
! 3355: ** <dd>The database filename is not allowed to be a symbolic link</dd>
! 3356: ** </dl>)^
! 3357: **
1.2 misho 3358: ** If the 3rd parameter to sqlite3_open_v2() is not one of the
1.4.2.3 ! misho 3359: ** required combinations shown above optionally combined with other
1.2 misho 3360: ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
3361: ** then the behavior is undefined.
3362: **
3363: ** ^The fourth parameter to sqlite3_open_v2() is the name of the
3364: ** [sqlite3_vfs] object that defines the operating system interface that
3365: ** the new database connection should use. ^If the fourth parameter is
3366: ** a NULL pointer then the default [sqlite3_vfs] object is used.
3367: **
3368: ** ^If the filename is ":memory:", then a private, temporary in-memory database
3369: ** is created for the connection. ^This in-memory database will vanish when
3370: ** the database connection is closed. Future versions of SQLite might
3371: ** make use of additional special filenames that begin with the ":" character.
3372: ** It is recommended that when a database filename actually does begin with
3373: ** a ":" character you should prefix the filename with a pathname such as
3374: ** "./" to avoid ambiguity.
3375: **
3376: ** ^If the filename is an empty string, then a private, temporary
3377: ** on-disk database will be created. ^This private database will be
3378: ** automatically deleted as soon as the database connection is closed.
3379: **
3380: ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
3381: **
3382: ** ^If [URI filename] interpretation is enabled, and the filename argument
3383: ** begins with "file:", then the filename is interpreted as a URI. ^URI
3384: ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
1.4.2.2 misho 3385: ** set in the third argument to sqlite3_open_v2(), or if it has
1.2 misho 3386: ** been enabled globally using the [SQLITE_CONFIG_URI] option with the
3387: ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
1.4.2.2 misho 3388: ** URI filename interpretation is turned off
1.2 misho 3389: ** by default, but future releases of SQLite might enable URI filename
3390: ** interpretation by default. See "[URI filenames]" for additional
3391: ** information.
3392: **
3393: ** URI filenames are parsed according to RFC 3986. ^If the URI contains an
1.4.2.3 ! misho 3394: ** authority, then it must be either an empty string or the string
! 3395: ** "localhost". ^If the authority is not an empty string or "localhost", an
! 3396: ** error is returned to the caller. ^The fragment component of a URI, if
1.2 misho 3397: ** present, is ignored.
3398: **
3399: ** ^SQLite uses the path component of the URI as the name of the disk file
1.4.2.3 ! misho 3400: ** which contains the database. ^If the path begins with a '/' character,
! 3401: ** then it is interpreted as an absolute path. ^If the path does not begin
1.2 misho 3402: ** with a '/' (meaning that the authority section is omitted from the URI)
1.4.2.3 ! misho 3403: ** then the path is interpreted as a relative path.
! 3404: ** ^(On windows, the first component of an absolute path
1.4 misho 3405: ** is a drive specification (e.g. "C:").)^
1.2 misho 3406: **
3407: ** [[core URI query parameters]]
3408: ** The query component of a URI may contain parameters that are interpreted
3409: ** either by SQLite itself, or by a [VFS | custom VFS implementation].
1.4 misho 3410: ** SQLite and its built-in [VFSes] interpret the
3411: ** following query parameters:
1.2 misho 3412: **
3413: ** <ul>
3414: ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
3415: ** a VFS object that provides the operating system interface that should
3416: ** be used to access the database file on disk. ^If this option is set to
3417: ** an empty string the default VFS object is used. ^Specifying an unknown
3418: ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
3419: ** present, then the VFS specified by the option takes precedence over
3420: ** the value passed as the fourth parameter to sqlite3_open_v2().
3421: **
1.3 misho 3422: ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
3423: ** "rwc", or "memory". Attempting to set it to any other value is
1.4.2.3 ! misho 3424: ** an error)^.
! 3425: ** ^If "ro" is specified, then the database is opened for read-only
! 3426: ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
! 3427: ** third argument to sqlite3_open_v2(). ^If the mode option is set to
! 3428: ** "rw", then the database is opened for read-write (but not create)
! 3429: ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
! 3430: ** been set. ^Value "rwc" is equivalent to setting both
1.3 misho 3431: ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is
3432: ** set to "memory" then a pure [in-memory database] that never reads
3433: ** or writes from disk is used. ^It is an error to specify a value for
3434: ** the mode parameter that is less restrictive than that specified by
3435: ** the flags passed in the third parameter to sqlite3_open_v2().
1.2 misho 3436: **
3437: ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
3438: ** "private". ^Setting it to "shared" is equivalent to setting the
3439: ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
1.4.2.3 ! misho 3440: ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is
1.2 misho 3441: ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
3442: ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in
1.4 misho 3443: ** a URI filename, its value overrides any behavior requested by setting
1.2 misho 3444: ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
1.4 misho 3445: **
3446: ** <li> <b>psow</b>: ^The psow parameter indicates whether or not the
3447: ** [powersafe overwrite] property does or does not apply to the
3448: ** storage media on which the database file resides.
3449: **
3450: ** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
3451: ** which if set disables file locking in rollback journal modes. This
3452: ** is useful for accessing a database on a filesystem that does not
3453: ** support locking. Caution: Database corruption might result if two
3454: ** or more processes write to the same database and any one of those
3455: ** processes uses nolock=1.
3456: **
3457: ** <li> <b>immutable</b>: ^The immutable parameter is a boolean query
3458: ** parameter that indicates that the database file is stored on
3459: ** read-only media. ^When immutable is set, SQLite assumes that the
3460: ** database file cannot be changed, even by a process with higher
3461: ** privilege, and so the database is opened read-only and all locking
3462: ** and change detection is disabled. Caution: Setting the immutable
3463: ** property on a database file that does in fact change can result
3464: ** in incorrect query results and/or [SQLITE_CORRUPT] errors.
3465: ** See also: [SQLITE_IOCAP_IMMUTABLE].
1.4.2.3 ! misho 3466: **
1.2 misho 3467: ** </ul>
3468: **
3469: ** ^Specifying an unknown parameter in the query component of a URI is not an
3470: ** error. Future versions of SQLite might understand additional query
3471: ** parameters. See "[query parameters with special meaning to SQLite]" for
3472: ** additional information.
3473: **
3474: ** [[URI filename examples]] <h3>URI filename examples</h3>
3475: **
3476: ** <table border="1" align=center cellpadding=5>
3477: ** <tr><th> URI filenames <th> Results
1.4.2.3 ! misho 3478: ** <tr><td> file:data.db <td>
1.2 misho 3479: ** Open the file "data.db" in the current directory.
3480: ** <tr><td> file:/home/fred/data.db<br>
1.4.2.3 ! misho 3481: ** file:///home/fred/data.db <br>
! 3482: ** file://localhost/home/fred/data.db <br> <td>
1.2 misho 3483: ** Open the database file "/home/fred/data.db".
1.4.2.3 ! misho 3484: ** <tr><td> file://darkstar/home/fred/data.db <td>
1.2 misho 3485: ** An error. "darkstar" is not a recognized authority.
1.4.2.3 ! misho 3486: ** <tr><td style="white-space:nowrap">
1.2 misho 3487: ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
3488: ** <td> Windows only: Open the file "data.db" on fred's desktop on drive
1.4.2.3 ! misho 3489: ** C:. Note that the %20 escaping in this example is not strictly
1.2 misho 3490: ** necessary - space characters can be used literally
3491: ** in URI filenames.
1.4.2.3 ! misho 3492: ** <tr><td> file:data.db?mode=ro&cache=private <td>
1.2 misho 3493: ** Open file "data.db" in the current directory for read-only access.
3494: ** Regardless of whether or not shared-cache mode is enabled by
3495: ** default, use a private cache.
1.4 misho 3496: ** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
3497: ** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
3498: ** that uses dot-files in place of posix advisory locking.
1.4.2.3 ! misho 3499: ** <tr><td> file:data.db?mode=readonly <td>
1.2 misho 3500: ** An error. "readonly" is not a valid option for the "mode" parameter.
3501: ** </table>
3502: **
3503: ** ^URI hexadecimal escape sequences (%HH) are supported within the path and
3504: ** query components of a URI. A hexadecimal escape sequence consists of a
1.4.2.3 ! misho 3505: ** percent sign - "%" - followed by exactly two hexadecimal digits
1.2 misho 3506: ** specifying an octet value. ^Before the path or query components of a
1.4.2.3 ! misho 3507: ** URI filename are interpreted, they are encoded using UTF-8 and all
1.2 misho 3508: ** hexadecimal escape sequences replaced by a single byte containing the
3509: ** corresponding octet. If this process generates an invalid UTF-8 encoding,
3510: ** the results are undefined.
3511: **
3512: ** <b>Note to Windows users:</b> The encoding used for the filename argument
3513: ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
3514: ** codepage is currently defined. Filenames containing international
3515: ** characters must be converted to UTF-8 prior to passing them into
3516: ** sqlite3_open() or sqlite3_open_v2().
1.3 misho 3517: **
3518: ** <b>Note to Windows Runtime users:</b> The temporary directory must be set
3519: ** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various
3520: ** features that require the use of temporary files may fail.
3521: **
3522: ** See also: [sqlite3_temp_directory]
1.2 misho 3523: */
3524: SQLITE_API int sqlite3_open(
3525: const char *filename, /* Database filename (UTF-8) */
3526: sqlite3 **ppDb /* OUT: SQLite db handle */
3527: );
3528: SQLITE_API int sqlite3_open16(
3529: const void *filename, /* Database filename (UTF-16) */
3530: sqlite3 **ppDb /* OUT: SQLite db handle */
3531: );
3532: SQLITE_API int sqlite3_open_v2(
3533: const char *filename, /* Database filename (UTF-8) */
3534: sqlite3 **ppDb, /* OUT: SQLite db handle */
3535: int flags, /* Flags */
3536: const char *zVfs /* Name of VFS module to use */
3537: );
3538:
3539: /*
3540: ** CAPI3REF: Obtain Values For URI Parameters
3541: **
1.4.2.3 ! misho 3542: ** These are utility routines, useful to [VFS|custom VFS implementations],
! 3543: ** that check if a database file was a URI that contained a specific query
1.2 misho 3544: ** parameter, and if so obtains the value of that query parameter.
3545: **
1.4.2.3 ! misho 3546: ** The first parameter to these interfaces (hereafter referred to
! 3547: ** as F) must be one of:
! 3548: ** <ul>
! 3549: ** <li> A database filename pointer created by the SQLite core and
! 3550: ** passed into the xOpen() method of a VFS implemention, or
! 3551: ** <li> A filename obtained from [sqlite3_db_filename()], or
! 3552: ** <li> A new filename constructed using [sqlite3_create_filename()].
! 3553: ** </ul>
! 3554: ** If the F parameter is not one of the above, then the behavior is
! 3555: ** undefined and probably undesirable. Older versions of SQLite were
! 3556: ** more tolerant of invalid F parameters than newer versions.
! 3557: **
! 3558: ** If F is a suitable filename (as described in the previous paragraph)
! 3559: ** and if P is the name of the query parameter, then
1.2 misho 3560: ** sqlite3_uri_parameter(F,P) returns the value of the P
1.4.2.3 ! misho 3561: ** parameter if it exists or a NULL pointer if P does not appear as a
! 3562: ** query parameter on F. If P is a query parameter of F and it
1.2 misho 3563: ** has no explicit value, then sqlite3_uri_parameter(F,P) returns
3564: ** a pointer to an empty string.
3565: **
3566: ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
3567: ** parameter and returns true (1) or false (0) according to the value
1.3 misho 3568: ** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
3569: ** value of query parameter P is one of "yes", "true", or "on" in any
1.4.2.3 ! misho 3570: ** case or if the value begins with a non-zero number. The
1.3 misho 3571: ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
3572: ** query parameter P is one of "no", "false", or "off" in any case or
3573: ** if the value begins with a numeric zero. If P is not a query
1.4.2.3 ! misho 3574: ** parameter on F or if the value of P does not match any of the
1.3 misho 3575: ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
1.2 misho 3576: **
3577: ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
3578: ** 64-bit signed integer and returns that integer, or D if P does not
3579: ** exist. If the value of P is something other than an integer, then
3580: ** zero is returned.
1.4.2.3 ! misho 3581: **
! 3582: ** The sqlite3_uri_key(F,N) returns a pointer to the name (not
! 3583: ** the value) of the N-th query parameter for filename F, or a NULL
! 3584: ** pointer if N is less than zero or greater than the number of query
! 3585: ** parameters minus 1. The N value is zero-based so N should be 0 to obtain
! 3586: ** the name of the first query parameter, 1 for the second parameter, and
! 3587: ** so forth.
! 3588: **
1.2 misho 3589: ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
3590: ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and
1.4.2.3 ! misho 3591: ** is not a database file pathname pointer that the SQLite core passed
! 3592: ** into the xOpen VFS method, then the behavior of this routine is undefined
! 3593: ** and probably undesirable.
! 3594: **
! 3595: ** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F
! 3596: ** parameter can also be the name of a rollback journal file or WAL file
! 3597: ** in addition to the main database file. Prior to version 3.31.0, these
! 3598: ** routines would only work if F was the name of the main database file.
! 3599: ** When the F parameter is the name of the rollback journal or WAL file,
! 3600: ** it has access to all the same query parameters as were found on the
! 3601: ** main database file.
1.4.2.2 misho 3602: **
3603: ** See the [URI filename] documentation for additional information.
1.2 misho 3604: */
3605: SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
3606: SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
3607: SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
1.4.2.3 ! misho 3608: SQLITE_API const char *sqlite3_uri_key(const char *zFilename, int N);
1.2 misho 3609:
1.4.2.3 ! misho 3610: /*
! 3611: ** CAPI3REF: Translate filenames
! 3612: **
! 3613: ** These routines are available to [VFS|custom VFS implementations] for
! 3614: ** translating filenames between the main database file, the journal file,
! 3615: ** and the WAL file.
! 3616: **
! 3617: ** If F is the name of an sqlite database file, journal file, or WAL file
! 3618: ** passed by the SQLite core into the VFS, then sqlite3_filename_database(F)
! 3619: ** returns the name of the corresponding database file.
! 3620: **
! 3621: ** If F is the name of an sqlite database file, journal file, or WAL file
! 3622: ** passed by the SQLite core into the VFS, or if F is a database filename
! 3623: ** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F)
! 3624: ** returns the name of the corresponding rollback journal file.
! 3625: **
! 3626: ** If F is the name of an sqlite database file, journal file, or WAL file
! 3627: ** that was passed by the SQLite core into the VFS, or if F is a database
! 3628: ** filename obtained from [sqlite3_db_filename()], then
! 3629: ** sqlite3_filename_wal(F) returns the name of the corresponding
! 3630: ** WAL file.
! 3631: **
! 3632: ** In all of the above, if F is not the name of a database, journal or WAL
! 3633: ** filename passed into the VFS from the SQLite core and F is not the
! 3634: ** return value from [sqlite3_db_filename()], then the result is
! 3635: ** undefined and is likely a memory access violation.
! 3636: */
! 3637: SQLITE_API const char *sqlite3_filename_database(const char*);
! 3638: SQLITE_API const char *sqlite3_filename_journal(const char*);
! 3639: SQLITE_API const char *sqlite3_filename_wal(const char*);
! 3640:
! 3641: /*
! 3642: ** CAPI3REF: Database File Corresponding To A Journal
! 3643: **
! 3644: ** ^If X is the name of a rollback or WAL-mode journal file that is
! 3645: ** passed into the xOpen method of [sqlite3_vfs], then
! 3646: ** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file]
! 3647: ** object that represents the main database file.
! 3648: **
! 3649: ** This routine is intended for use in custom [VFS] implementations
! 3650: ** only. It is not a general-purpose interface.
! 3651: ** The argument sqlite3_file_object(X) must be a filename pointer that
! 3652: ** has been passed into [sqlite3_vfs].xOpen method where the
! 3653: ** flags parameter to xOpen contains one of the bits
! 3654: ** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use
! 3655: ** of this routine results in undefined and probably undesirable
! 3656: ** behavior.
! 3657: */
! 3658: SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*);
! 3659:
! 3660: /*
! 3661: ** CAPI3REF: Create and Destroy VFS Filenames
! 3662: **
! 3663: ** These interfces are provided for use by [VFS shim] implementations and
! 3664: ** are not useful outside of that context.
! 3665: **
! 3666: ** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of
! 3667: ** database filename D with corresponding journal file J and WAL file W and
! 3668: ** with N URI parameters key/values pairs in the array P. The result from
! 3669: ** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that
! 3670: ** is safe to pass to routines like:
! 3671: ** <ul>
! 3672: ** <li> [sqlite3_uri_parameter()],
! 3673: ** <li> [sqlite3_uri_boolean()],
! 3674: ** <li> [sqlite3_uri_int64()],
! 3675: ** <li> [sqlite3_uri_key()],
! 3676: ** <li> [sqlite3_filename_database()],
! 3677: ** <li> [sqlite3_filename_journal()], or
! 3678: ** <li> [sqlite3_filename_wal()].
! 3679: ** </ul>
! 3680: ** If a memory allocation error occurs, sqlite3_create_filename() might
! 3681: ** return a NULL pointer. The memory obtained from sqlite3_create_filename(X)
! 3682: ** must be released by a corresponding call to sqlite3_free_filename(Y).
! 3683: **
! 3684: ** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array
! 3685: ** of 2*N pointers to strings. Each pair of pointers in this array corresponds
! 3686: ** to a key and value for a query parameter. The P parameter may be a NULL
! 3687: ** pointer if N is zero. None of the 2*N pointers in the P array may be
! 3688: ** NULL pointers and key pointers should not be empty strings.
! 3689: ** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may
! 3690: ** be NULL pointers, though they can be empty strings.
! 3691: **
! 3692: ** The sqlite3_free_filename(Y) routine releases a memory allocation
! 3693: ** previously obtained from sqlite3_create_filename(). Invoking
! 3694: ** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op.
! 3695: **
! 3696: ** If the Y parameter to sqlite3_free_filename(Y) is anything other
! 3697: ** than a NULL pointer or a pointer previously acquired from
! 3698: ** sqlite3_create_filename(), then bad things such as heap
! 3699: ** corruption or segfaults may occur. The value Y should be
! 3700: ** used again after sqlite3_free_filename(Y) has been called. This means
! 3701: ** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y,
! 3702: ** then the corresponding [sqlite3_module.xClose() method should also be
! 3703: ** invoked prior to calling sqlite3_free_filename(Y).
! 3704: */
! 3705: SQLITE_API char *sqlite3_create_filename(
! 3706: const char *zDatabase,
! 3707: const char *zJournal,
! 3708: const char *zWal,
! 3709: int nParam,
! 3710: const char **azParam
! 3711: );
! 3712: SQLITE_API void sqlite3_free_filename(char*);
1.2 misho 3713:
3714: /*
3715: ** CAPI3REF: Error Codes And Messages
1.4 misho 3716: ** METHOD: sqlite3
1.2 misho 3717: **
1.4.2.3 ! misho 3718: ** ^If the most recent sqlite3_* API call associated with
1.4 misho 3719: ** [database connection] D failed, then the sqlite3_errcode(D) interface
3720: ** returns the numeric [result code] or [extended result code] for that
3721: ** API call.
3722: ** ^The sqlite3_extended_errcode()
1.4.2.3 ! misho 3723: ** interface is the same except that it always returns the
1.2 misho 3724: ** [extended result code] even when extended result codes are
3725: ** disabled.
3726: **
1.4.2.2 misho 3727: ** The values returned by sqlite3_errcode() and/or
3728: ** sqlite3_extended_errcode() might change with each API call.
3729: ** Except, there are some interfaces that are guaranteed to never
3730: ** change the value of the error code. The error-code preserving
3731: ** interfaces are:
3732: **
3733: ** <ul>
3734: ** <li> sqlite3_errcode()
3735: ** <li> sqlite3_extended_errcode()
3736: ** <li> sqlite3_errmsg()
3737: ** <li> sqlite3_errmsg16()
3738: ** </ul>
3739: **
1.2 misho 3740: ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
3741: ** text that describes the error, as either UTF-8 or UTF-16 respectively.
3742: ** ^(Memory to hold the error message string is managed internally.
3743: ** The application does not need to worry about freeing the result.
3744: ** However, the error string might be overwritten or deallocated by
3745: ** subsequent calls to other SQLite interface functions.)^
3746: **
1.3 misho 3747: ** ^The sqlite3_errstr() interface returns the English-language text
3748: ** that describes the [result code], as UTF-8.
3749: ** ^(Memory to hold the error message string is managed internally
3750: ** and must not be freed by the application)^.
3751: **
1.2 misho 3752: ** When the serialized [threading mode] is in use, it might be the
3753: ** case that a second error occurs on a separate thread in between
3754: ** the time of the first error and the call to these interfaces.
3755: ** When that happens, the second error will be reported since these
3756: ** interfaces always report the most recent result. To avoid
3757: ** this, each thread can obtain exclusive use of the [database connection] D
3758: ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
3759: ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
3760: ** all calls to the interfaces listed here are completed.
3761: **
3762: ** If an interface fails with SQLITE_MISUSE, that means the interface
3763: ** was invoked incorrectly by the application. In that case, the
3764: ** error code and message may or may not be set.
3765: */
3766: SQLITE_API int sqlite3_errcode(sqlite3 *db);
3767: SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
3768: SQLITE_API const char *sqlite3_errmsg(sqlite3*);
3769: SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
1.3 misho 3770: SQLITE_API const char *sqlite3_errstr(int);
1.2 misho 3771:
3772: /*
1.4 misho 3773: ** CAPI3REF: Prepared Statement Object
1.2 misho 3774: ** KEYWORDS: {prepared statement} {prepared statements}
3775: **
1.4 misho 3776: ** An instance of this object represents a single SQL statement that
3777: ** has been compiled into binary form and is ready to be evaluated.
3778: **
3779: ** Think of each SQL statement as a separate computer program. The
1.4.2.3 ! misho 3780: ** original SQL text is source code. A prepared statement object
1.4 misho 3781: ** is the compiled object code. All SQL must be converted into a
3782: ** prepared statement before it can be run.
1.2 misho 3783: **
1.4 misho 3784: ** The life-cycle of a prepared statement object usually goes like this:
1.2 misho 3785: **
3786: ** <ol>
1.4 misho 3787: ** <li> Create the prepared statement object using [sqlite3_prepare_v2()].
3788: ** <li> Bind values to [parameters] using the sqlite3_bind_*()
1.2 misho 3789: ** interfaces.
3790: ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
1.4 misho 3791: ** <li> Reset the prepared statement using [sqlite3_reset()] then go back
1.2 misho 3792: ** to step 2. Do this zero or more times.
3793: ** <li> Destroy the object using [sqlite3_finalize()].
3794: ** </ol>
3795: */
3796: typedef struct sqlite3_stmt sqlite3_stmt;
3797:
3798: /*
3799: ** CAPI3REF: Run-time Limits
1.4 misho 3800: ** METHOD: sqlite3
1.2 misho 3801: **
3802: ** ^(This interface allows the size of various constructs to be limited
3803: ** on a connection by connection basis. The first parameter is the
3804: ** [database connection] whose limit is to be set or queried. The
3805: ** second parameter is one of the [limit categories] that define a
3806: ** class of constructs to be size limited. The third parameter is the
3807: ** new limit for that construct.)^
3808: **
3809: ** ^If the new limit is a negative number, the limit is unchanged.
1.4.2.3 ! misho 3810: ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
1.2 misho 3811: ** [limits | hard upper bound]
3812: ** set at compile-time by a C preprocessor macro called
3813: ** [limits | SQLITE_MAX_<i>NAME</i>].
3814: ** (The "_LIMIT_" in the name is changed to "_MAX_".))^
3815: ** ^Attempts to increase a limit above its hard upper bound are
3816: ** silently truncated to the hard upper bound.
3817: **
1.4.2.3 ! misho 3818: ** ^Regardless of whether or not the limit was changed, the
1.2 misho 3819: ** [sqlite3_limit()] interface returns the prior value of the limit.
3820: ** ^Hence, to find the current value of a limit without changing it,
3821: ** simply invoke this interface with the third parameter set to -1.
3822: **
3823: ** Run-time limits are intended for use in applications that manage
3824: ** both their own internal database and also databases that are controlled
3825: ** by untrusted external sources. An example application might be a
3826: ** web browser that has its own databases for storing history and
3827: ** separate databases controlled by JavaScript applications downloaded
3828: ** off the Internet. The internal databases can be given the
3829: ** large, default limits. Databases managed by external sources can
3830: ** be given much smaller limits designed to prevent a denial of service
3831: ** attack. Developers might also want to use the [sqlite3_set_authorizer()]
3832: ** interface to further control untrusted SQL. The size of the database
3833: ** created by an untrusted script can be contained using the
3834: ** [max_page_count] [PRAGMA].
3835: **
3836: ** New run-time limit categories may be added in future releases.
3837: */
3838: SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
3839:
3840: /*
3841: ** CAPI3REF: Run-Time Limit Categories
3842: ** KEYWORDS: {limit category} {*limit categories}
3843: **
3844: ** These constants define various performance limits
3845: ** that can be lowered at run-time using [sqlite3_limit()].
3846: ** The synopsis of the meanings of the various limits is shown below.
3847: ** Additional information is available at [limits | Limits in SQLite].
3848: **
3849: ** <dl>
3850: ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
3851: ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
3852: **
3853: ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
3854: ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
3855: **
3856: ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
3857: ** <dd>The maximum number of columns in a table definition or in the
3858: ** result set of a [SELECT] or the maximum number of columns in an index
3859: ** or in an ORDER BY or GROUP BY clause.</dd>)^
3860: **
3861: ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
3862: ** <dd>The maximum depth of the parse tree on any expression.</dd>)^
3863: **
3864: ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
3865: ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
3866: **
3867: ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
3868: ** <dd>The maximum number of instructions in a virtual machine program
1.4.2.1 misho 3869: ** used to implement an SQL statement. If [sqlite3_prepare_v2()] or
3870: ** the equivalent tries to allocate space for more than this many opcodes
3871: ** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^
1.2 misho 3872: **
3873: ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
3874: ** <dd>The maximum number of arguments on a function.</dd>)^
3875: **
3876: ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
3877: ** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
3878: **
3879: ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
3880: ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
3881: ** <dd>The maximum length of the pattern argument to the [LIKE] or
3882: ** [GLOB] operators.</dd>)^
3883: **
3884: ** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
3885: ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
3886: ** <dd>The maximum index number of any [parameter] in an SQL statement.)^
3887: **
3888: ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
3889: ** <dd>The maximum depth of recursion for triggers.</dd>)^
1.4 misho 3890: **
3891: ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
3892: ** <dd>The maximum number of auxiliary worker threads that a single
3893: ** [prepared statement] may start.</dd>)^
1.2 misho 3894: ** </dl>
3895: */
3896: #define SQLITE_LIMIT_LENGTH 0
3897: #define SQLITE_LIMIT_SQL_LENGTH 1
3898: #define SQLITE_LIMIT_COLUMN 2
3899: #define SQLITE_LIMIT_EXPR_DEPTH 3
3900: #define SQLITE_LIMIT_COMPOUND_SELECT 4
3901: #define SQLITE_LIMIT_VDBE_OP 5
3902: #define SQLITE_LIMIT_FUNCTION_ARG 6
3903: #define SQLITE_LIMIT_ATTACHED 7
3904: #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
3905: #define SQLITE_LIMIT_VARIABLE_NUMBER 9
3906: #define SQLITE_LIMIT_TRIGGER_DEPTH 10
1.4 misho 3907: #define SQLITE_LIMIT_WORKER_THREADS 11
1.2 misho 3908:
1.4.2.2 misho 3909: /*
3910: ** CAPI3REF: Prepare Flags
3911: **
3912: ** These constants define various flags that can be passed into
3913: ** "prepFlags" parameter of the [sqlite3_prepare_v3()] and
3914: ** [sqlite3_prepare16_v3()] interfaces.
3915: **
3916: ** New flags may be added in future releases of SQLite.
3917: **
3918: ** <dl>
3919: ** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt>
3920: ** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner
3921: ** that the prepared statement will be retained for a long time and
3922: ** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()]
1.4.2.3 ! misho 3923: ** and [sqlite3_prepare16_v3()] assume that the prepared statement will
1.4.2.2 misho 3924: ** be used just once or at most a few times and then destroyed using
3925: ** [sqlite3_finalize()] relatively soon. The current implementation acts
3926: ** on this hint by avoiding the use of [lookaside memory] so as not to
3927: ** deplete the limited store of lookaside memory. Future versions of
3928: ** SQLite may act on this hint differently.
3929: **
3930: ** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt>
3931: ** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used
3932: ** to be required for any prepared statement that wanted to use the
3933: ** [sqlite3_normalized_sql()] interface. However, the
3934: ** [sqlite3_normalized_sql()] interface is now available to all
3935: ** prepared statements, regardless of whether or not they use this
3936: ** flag.
3937: **
3938: ** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt>
3939: ** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler
3940: ** to return an error (error code SQLITE_ERROR) if the statement uses
3941: ** any virtual tables.
3942: ** </dl>
3943: */
3944: #define SQLITE_PREPARE_PERSISTENT 0x01
3945: #define SQLITE_PREPARE_NORMALIZE 0x02
3946: #define SQLITE_PREPARE_NO_VTAB 0x04
1.4.2.1 misho 3947:
1.2 misho 3948: /*
3949: ** CAPI3REF: Compiling An SQL Statement
3950: ** KEYWORDS: {SQL statement compiler}
1.4 misho 3951: ** METHOD: sqlite3
3952: ** CONSTRUCTOR: sqlite3_stmt
1.2 misho 3953: **
1.4.2.2 misho 3954: ** To execute an SQL statement, it must first be compiled into a byte-code
3955: ** program using one of these routines. Or, in other words, these routines
3956: ** are constructors for the [prepared statement] object.
3957: **
3958: ** The preferred routine to use is [sqlite3_prepare_v2()]. The
3959: ** [sqlite3_prepare()] interface is legacy and should be avoided.
3960: ** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used
3961: ** for special purposes.
3962: **
3963: ** The use of the UTF-8 interfaces is preferred, as SQLite currently
3964: ** does all parsing using UTF-8. The UTF-16 interfaces are provided
3965: ** as a convenience. The UTF-16 interfaces work by converting the
3966: ** input text into UTF-8, then invoking the corresponding UTF-8 interface.
1.2 misho 3967: **
3968: ** The first argument, "db", is a [database connection] obtained from a
3969: ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
3970: ** [sqlite3_open16()]. The database connection must not have been closed.
3971: **
3972: ** The second argument, "zSql", is the statement to be compiled, encoded
1.4.2.2 misho 3973: ** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(),
3974: ** and sqlite3_prepare_v3()
3975: ** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(),
3976: ** and sqlite3_prepare16_v3() use UTF-16.
1.2 misho 3977: **
1.4 misho 3978: ** ^If the nByte argument is negative, then zSql is read up to the
3979: ** first zero terminator. ^If nByte is positive, then it is the
3980: ** number of bytes read from zSql. ^If nByte is zero, then no prepared
3981: ** statement is generated.
3982: ** If the caller knows that the supplied string is nul-terminated, then
3983: ** there is a small performance advantage to passing an nByte parameter that
3984: ** is the number of bytes in the input string <i>including</i>
3985: ** the nul-terminator.
1.2 misho 3986: **
3987: ** ^If pzTail is not NULL then *pzTail is made to point to the first byte
3988: ** past the end of the first SQL statement in zSql. These routines only
3989: ** compile the first statement in zSql, so *pzTail is left pointing to
3990: ** what remains uncompiled.
3991: **
3992: ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
3993: ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
3994: ** to NULL. ^If the input text contains no SQL (if the input is an empty
3995: ** string or a comment) then *ppStmt is set to NULL.
3996: ** The calling procedure is responsible for deleting the compiled
3997: ** SQL statement using [sqlite3_finalize()] after it has finished with it.
3998: ** ppStmt may not be NULL.
3999: **
4000: ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
4001: ** otherwise an [error code] is returned.
4002: **
1.4.2.2 misho 4003: ** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(),
4004: ** and sqlite3_prepare16_v3() interfaces are recommended for all new programs.
4005: ** The older interfaces (sqlite3_prepare() and sqlite3_prepare16())
4006: ** are retained for backwards compatibility, but their use is discouraged.
4007: ** ^In the "vX" interfaces, the prepared statement
1.2 misho 4008: ** that is returned (the [sqlite3_stmt] object) contains a copy of the
4009: ** original SQL text. This causes the [sqlite3_step()] interface to
4010: ** behave differently in three ways:
4011: **
4012: ** <ol>
4013: ** <li>
4014: ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
4015: ** always used to do, [sqlite3_step()] will automatically recompile the SQL
1.4 misho 4016: ** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
4017: ** retries will occur before sqlite3_step() gives up and returns an error.
1.2 misho 4018: ** </li>
4019: **
4020: ** <li>
4021: ** ^When an error occurs, [sqlite3_step()] will return one of the detailed
4022: ** [error codes] or [extended error codes]. ^The legacy behavior was that
4023: ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
4024: ** and the application would have to make a second call to [sqlite3_reset()]
4025: ** in order to find the underlying cause of the problem. With the "v2" prepare
4026: ** interfaces, the underlying reason for the error is returned immediately.
4027: ** </li>
4028: **
4029: ** <li>
1.4.2.3 ! misho 4030: ** ^If the specific value bound to a [parameter | host parameter] in the
1.2 misho 4031: ** WHERE clause might influence the choice of query plan for a statement,
1.4.2.3 ! misho 4032: ** then the statement will be automatically recompiled, as if there had been
! 4033: ** a schema change, on the first [sqlite3_step()] call following any change
! 4034: ** to the [sqlite3_bind_text | bindings] of that [parameter].
! 4035: ** ^The specific value of a WHERE-clause [parameter] might influence the
1.2 misho 4036: ** choice of query plan if the parameter is the left-hand side of a [LIKE]
4037: ** or [GLOB] operator or if the parameter is compared to an indexed column
1.4.2.3 ! misho 4038: ** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled.
1.2 misho 4039: ** </li>
4040: ** </ol>
1.4.2.2 misho 4041: **
4042: ** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having
4043: ** the extra prepFlags parameter, which is a bit array consisting of zero or
4044: ** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The
4045: ** sqlite3_prepare_v2() interface works exactly the same as
4046: ** sqlite3_prepare_v3() with a zero prepFlags parameter.
1.2 misho 4047: */
4048: SQLITE_API int sqlite3_prepare(
4049: sqlite3 *db, /* Database handle */
4050: const char *zSql, /* SQL statement, UTF-8 encoded */
4051: int nByte, /* Maximum length of zSql in bytes. */
4052: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4053: const char **pzTail /* OUT: Pointer to unused portion of zSql */
4054: );
4055: SQLITE_API int sqlite3_prepare_v2(
4056: sqlite3 *db, /* Database handle */
4057: const char *zSql, /* SQL statement, UTF-8 encoded */
4058: int nByte, /* Maximum length of zSql in bytes. */
4059: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4060: const char **pzTail /* OUT: Pointer to unused portion of zSql */
4061: );
1.4.2.2 misho 4062: SQLITE_API int sqlite3_prepare_v3(
4063: sqlite3 *db, /* Database handle */
4064: const char *zSql, /* SQL statement, UTF-8 encoded */
4065: int nByte, /* Maximum length of zSql in bytes. */
4066: unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4067: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4068: const char **pzTail /* OUT: Pointer to unused portion of zSql */
4069: );
1.2 misho 4070: SQLITE_API int sqlite3_prepare16(
4071: sqlite3 *db, /* Database handle */
4072: const void *zSql, /* SQL statement, UTF-16 encoded */
4073: int nByte, /* Maximum length of zSql in bytes. */
4074: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4075: const void **pzTail /* OUT: Pointer to unused portion of zSql */
4076: );
4077: SQLITE_API int sqlite3_prepare16_v2(
4078: sqlite3 *db, /* Database handle */
4079: const void *zSql, /* SQL statement, UTF-16 encoded */
4080: int nByte, /* Maximum length of zSql in bytes. */
4081: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4082: const void **pzTail /* OUT: Pointer to unused portion of zSql */
4083: );
1.4.2.2 misho 4084: SQLITE_API int sqlite3_prepare16_v3(
4085: sqlite3 *db, /* Database handle */
4086: const void *zSql, /* SQL statement, UTF-16 encoded */
4087: int nByte, /* Maximum length of zSql in bytes. */
4088: unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4089: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4090: const void **pzTail /* OUT: Pointer to unused portion of zSql */
4091: );
1.2 misho 4092:
4093: /*
4094: ** CAPI3REF: Retrieving Statement SQL
1.4 misho 4095: ** METHOD: sqlite3_stmt
1.2 misho 4096: **
1.4 misho 4097: ** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
4098: ** SQL text used to create [prepared statement] P if P was
1.4.2.2 misho 4099: ** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()],
4100: ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
1.4 misho 4101: ** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
4102: ** string containing the SQL text of prepared statement P with
4103: ** [bound parameters] expanded.
1.4.2.2 misho 4104: ** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8
4105: ** string containing the normalized SQL text of prepared statement P. The
4106: ** semantics used to normalize a SQL statement are unspecified and subject
4107: ** to change. At a minimum, literal values will be replaced with suitable
4108: ** placeholders.
1.4 misho 4109: **
4110: ** ^(For example, if a prepared statement is created using the SQL
4111: ** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
4112: ** and parameter :xyz is unbound, then sqlite3_sql() will return
4113: ** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
4114: ** will return "SELECT 2345,NULL".)^
4115: **
4116: ** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
4117: ** is available to hold the result, or if the result would exceed the
4118: ** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].
4119: **
4120: ** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
4121: ** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time
4122: ** option causes sqlite3_expanded_sql() to always return NULL.
4123: **
1.4.2.2 misho 4124: ** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P)
4125: ** are managed by SQLite and are automatically freed when the prepared
4126: ** statement is finalized.
1.4 misho 4127: ** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
4128: ** is obtained from [sqlite3_malloc()] and must be free by the application
4129: ** by passing it to [sqlite3_free()].
1.2 misho 4130: */
4131: SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
1.4 misho 4132: SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt);
1.4.2.2 misho 4133: SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt);
1.2 misho 4134:
4135: /*
4136: ** CAPI3REF: Determine If An SQL Statement Writes The Database
1.4 misho 4137: ** METHOD: sqlite3_stmt
1.2 misho 4138: **
4139: ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
4140: ** and only if the [prepared statement] X makes no direct changes to
4141: ** the content of the database file.
4142: **
4143: ** Note that [application-defined SQL functions] or
1.4.2.3 ! misho 4144: ** [virtual tables] might change the database indirectly as a side effect.
! 4145: ** ^(For example, if an application defines a function "eval()" that
1.2 misho 4146: ** calls [sqlite3_exec()], then the following SQL statement would
4147: ** change the database file through side-effects:
4148: **
4149: ** <blockquote><pre>
4150: ** SELECT eval('DELETE FROM t1') FROM t2;
4151: ** </pre></blockquote>
4152: **
4153: ** But because the [SELECT] statement does not change the database file
4154: ** directly, sqlite3_stmt_readonly() would still return true.)^
4155: **
4156: ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
4157: ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
4158: ** since the statements themselves do not actually modify the database but
1.4.2.3 ! misho 4159: ** rather they control the timing of when other statements modify the
1.2 misho 4160: ** database. ^The [ATTACH] and [DETACH] statements also cause
4161: ** sqlite3_stmt_readonly() to return true since, while those statements
1.4.2.3 ! misho 4162: ** change the configuration of a database connection, they do not make
1.2 misho 4163: ** changes to the content of the database files on disk.
1.4.2.1 misho 4164: ** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
4165: ** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
4166: ** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
4167: ** sqlite3_stmt_readonly() returns false for those commands.
1.2 misho 4168: */
4169: SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
4170:
4171: /*
1.4.2.2 misho 4172: ** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement
4173: ** METHOD: sqlite3_stmt
4174: **
4175: ** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the
4176: ** prepared statement S is an EXPLAIN statement, or 2 if the
4177: ** statement S is an EXPLAIN QUERY PLAN.
4178: ** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is
4179: ** an ordinary statement or a NULL pointer.
4180: */
4181: SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt);
4182:
4183: /*
1.2 misho 4184: ** CAPI3REF: Determine If A Prepared Statement Has Been Reset
1.4 misho 4185: ** METHOD: sqlite3_stmt
1.2 misho 4186: **
4187: ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
1.4.2.3 ! misho 4188: ** [prepared statement] S has been stepped at least once using
1.4 misho 4189: ** [sqlite3_step(S)] but has neither run to completion (returned
4190: ** [SQLITE_DONE] from [sqlite3_step(S)]) nor
1.2 misho 4191: ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)
1.4.2.3 ! misho 4192: ** interface returns false if S is a NULL pointer. If S is not a
1.2 misho 4193: ** NULL pointer and is not a pointer to a valid [prepared statement]
4194: ** object, then the behavior is undefined and probably undesirable.
4195: **
4196: ** This interface can be used in combination [sqlite3_next_stmt()]
1.4.2.3 ! misho 4197: ** to locate all prepared statements associated with a database
1.2 misho 4198: ** connection that are in need of being reset. This can be used,
1.4.2.3 ! misho 4199: ** for example, in diagnostic routines to search for prepared
1.2 misho 4200: ** statements that are holding a transaction open.
4201: */
4202: SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
4203:
4204: /*
4205: ** CAPI3REF: Dynamically Typed Value Object
4206: ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
4207: **
4208: ** SQLite uses the sqlite3_value object to represent all values
4209: ** that can be stored in a database table. SQLite uses dynamic typing
4210: ** for the values it stores. ^Values stored in sqlite3_value objects
4211: ** can be integers, floating point values, strings, BLOBs, or NULL.
4212: **
4213: ** An sqlite3_value object may be either "protected" or "unprotected".
4214: ** Some interfaces require a protected sqlite3_value. Other interfaces
4215: ** will accept either a protected or an unprotected sqlite3_value.
4216: ** Every interface that accepts sqlite3_value arguments specifies
1.4 misho 4217: ** whether or not it requires a protected sqlite3_value. The
1.4.2.3 ! misho 4218: ** [sqlite3_value_dup()] interface can be used to construct a new
1.4 misho 4219: ** protected sqlite3_value from an unprotected sqlite3_value.
1.2 misho 4220: **
4221: ** The terms "protected" and "unprotected" refer to whether or not
4222: ** a mutex is held. An internal mutex is held for a protected
4223: ** sqlite3_value object but no mutex is held for an unprotected
4224: ** sqlite3_value object. If SQLite is compiled to be single-threaded
4225: ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
1.4.2.3 ! misho 4226: ** or if SQLite is run in one of reduced mutex modes
1.2 misho 4227: ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
4228: ** then there is no distinction between protected and unprotected
4229: ** sqlite3_value objects and they can be used interchangeably. However,
4230: ** for maximum code portability it is recommended that applications
4231: ** still make the distinction between protected and unprotected
4232: ** sqlite3_value objects even when not strictly required.
4233: **
4234: ** ^The sqlite3_value objects that are passed as parameters into the
4235: ** implementation of [application-defined SQL functions] are protected.
4236: ** ^The sqlite3_value object returned by
4237: ** [sqlite3_column_value()] is unprotected.
1.4.2.2 misho 4238: ** Unprotected sqlite3_value objects may only be used as arguments
4239: ** to [sqlite3_result_value()], [sqlite3_bind_value()], and
4240: ** [sqlite3_value_dup()].
1.2 misho 4241: ** The [sqlite3_value_blob | sqlite3_value_type()] family of
4242: ** interfaces require protected sqlite3_value objects.
4243: */
1.4.2.1 misho 4244: typedef struct sqlite3_value sqlite3_value;
1.2 misho 4245:
4246: /*
4247: ** CAPI3REF: SQL Function Context Object
4248: **
4249: ** The context in which an SQL function executes is stored in an
4250: ** sqlite3_context object. ^A pointer to an sqlite3_context object
4251: ** is always first parameter to [application-defined SQL functions].
4252: ** The application-defined SQL function implementation will pass this
4253: ** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
4254: ** [sqlite3_aggregate_context()], [sqlite3_user_data()],
4255: ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
4256: ** and/or [sqlite3_set_auxdata()].
4257: */
4258: typedef struct sqlite3_context sqlite3_context;
4259:
4260: /*
4261: ** CAPI3REF: Binding Values To Prepared Statements
4262: ** KEYWORDS: {host parameter} {host parameters} {host parameter name}
4263: ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
1.4 misho 4264: ** METHOD: sqlite3_stmt
1.2 misho 4265: **
4266: ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
4267: ** literals may be replaced by a [parameter] that matches one of following
4268: ** templates:
4269: **
4270: ** <ul>
4271: ** <li> ?
4272: ** <li> ?NNN
4273: ** <li> :VVV
4274: ** <li> @VVV
4275: ** <li> $VVV
4276: ** </ul>
4277: **
4278: ** In the templates above, NNN represents an integer literal,
4279: ** and VVV represents an alphanumeric identifier.)^ ^The values of these
4280: ** parameters (also called "host parameter names" or "SQL parameters")
4281: ** can be set using the sqlite3_bind_*() routines defined here.
4282: **
4283: ** ^The first argument to the sqlite3_bind_*() routines is always
4284: ** a pointer to the [sqlite3_stmt] object returned from
4285: ** [sqlite3_prepare_v2()] or its variants.
4286: **
4287: ** ^The second argument is the index of the SQL parameter to be set.
4288: ** ^The leftmost SQL parameter has an index of 1. ^When the same named
4289: ** SQL parameter is used more than once, second and subsequent
4290: ** occurrences have the same index as the first occurrence.
4291: ** ^The index for named parameters can be looked up using the
4292: ** [sqlite3_bind_parameter_index()] API if desired. ^The index
4293: ** for "?NNN" parameters is the value of NNN.
4294: ** ^The NNN value must be between 1 and the [sqlite3_limit()]
1.4.2.3 ! misho 4295: ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766).
1.2 misho 4296: **
4297: ** ^The third argument is the value to bind to the parameter.
1.4 misho 4298: ** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4299: ** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
4300: ** is ignored and the end result is the same as sqlite3_bind_null().
1.4.2.3 ! misho 4301: ** ^If the third parameter to sqlite3_bind_text() is not NULL, then
! 4302: ** it should be a pointer to well-formed UTF8 text.
! 4303: ** ^If the third parameter to sqlite3_bind_text16() is not NULL, then
! 4304: ** it should be a pointer to well-formed UTF16 text.
! 4305: ** ^If the third parameter to sqlite3_bind_text64() is not NULL, then
! 4306: ** it should be a pointer to a well-formed unicode string that is
! 4307: ** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16
! 4308: ** otherwise.
! 4309: **
! 4310: ** [[byte-order determination rules]] ^The byte-order of
! 4311: ** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF)
! 4312: ** found in first character, which is removed, or in the absence of a BOM
! 4313: ** the byte order is the native byte order of the host
! 4314: ** machine for sqlite3_bind_text16() or the byte order specified in
! 4315: ** the 6th parameter for sqlite3_bind_text64().)^
! 4316: ** ^If UTF16 input text contains invalid unicode
! 4317: ** characters, then SQLite might change those invalid characters
! 4318: ** into the unicode replacement character: U+FFFD.
1.2 misho 4319: **
4320: ** ^(In those routines that have a fourth argument, its value is the
4321: ** number of bytes in the parameter. To be clear: the value is the
4322: ** number of <u>bytes</u> in the value, not the number of characters.)^
1.3 misho 4323: ** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4324: ** is negative, then the length of the string is
1.2 misho 4325: ** the number of bytes up to the first zero terminator.
1.3 misho 4326: ** If the fourth parameter to sqlite3_bind_blob() is negative, then
4327: ** the behavior is undefined.
1.2 misho 4328: ** If a non-negative fourth parameter is provided to sqlite3_bind_text()
1.4 misho 4329: ** or sqlite3_bind_text16() or sqlite3_bind_text64() then
4330: ** that parameter must be the byte offset
1.2 misho 4331: ** where the NUL terminator would occur assuming the string were NUL
1.4.2.3 ! misho 4332: ** terminated. If any NUL characters occurs at byte offsets less than
1.2 misho 4333: ** the value of the fourth parameter then the resulting string value will
4334: ** contain embedded NULs. The result of expressions involving strings
4335: ** with embedded NULs is undefined.
4336: **
1.4 misho 4337: ** ^The fifth argument to the BLOB and string binding interfaces
4338: ** is a destructor used to dispose of the BLOB or
1.2 misho 4339: ** string after SQLite has finished with it. ^The destructor is called
1.4.2.2 misho 4340: ** to dispose of the BLOB or string even if the call to the bind API fails,
4341: ** except the destructor is not called if the third parameter is a NULL
4342: ** pointer or the fourth parameter is negative.
1.2 misho 4343: ** ^If the fifth argument is
4344: ** the special value [SQLITE_STATIC], then SQLite assumes that the
4345: ** information is in static, unmanaged space and does not need to be freed.
4346: ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
4347: ** SQLite makes its own private copy of the data immediately, before
4348: ** the sqlite3_bind_*() routine returns.
4349: **
1.4 misho 4350: ** ^The sixth argument to sqlite3_bind_text64() must be one of
4351: ** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
4352: ** to specify the encoding of the text in the third parameter. If
4353: ** the sixth argument to sqlite3_bind_text64() is not one of the
4354: ** allowed values shown above, or if the text encoding is different
4355: ** from the encoding specified by the sixth parameter, then the behavior
4356: ** is undefined.
4357: **
1.2 misho 4358: ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
4359: ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
4360: ** (just an integer to hold its size) while it is being processed.
4361: ** Zeroblobs are intended to serve as placeholders for BLOBs whose
4362: ** content is later written using
4363: ** [sqlite3_blob_open | incremental BLOB I/O] routines.
4364: ** ^A negative value for the zeroblob results in a zero-length BLOB.
4365: **
1.4.2.2 misho 4366: ** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in
4367: ** [prepared statement] S to have an SQL value of NULL, but to also be
4368: ** associated with the pointer P of type T. ^D is either a NULL pointer or
4369: ** a pointer to a destructor function for P. ^SQLite will invoke the
4370: ** destructor D with a single argument of P when it is finished using
4371: ** P. The T parameter should be a static string, preferably a string
4372: ** literal. The sqlite3_bind_pointer() routine is part of the
4373: ** [pointer passing interface] added for SQLite 3.20.0.
4374: **
1.2 misho 4375: ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
4376: ** for the [prepared statement] or with a prepared statement for which
4377: ** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
4378: ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
4379: ** routine is passed a [prepared statement] that has been finalized, the
4380: ** result is undefined and probably harmful.
4381: **
4382: ** ^Bindings are not cleared by the [sqlite3_reset()] routine.
4383: ** ^Unbound parameters are interpreted as NULL.
4384: **
4385: ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
4386: ** [error code] if anything goes wrong.
1.4 misho 4387: ** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
4388: ** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
4389: ** [SQLITE_MAX_LENGTH].
1.2 misho 4390: ** ^[SQLITE_RANGE] is returned if the parameter
4391: ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
4392: **
4393: ** See also: [sqlite3_bind_parameter_count()],
4394: ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
4395: */
4396: SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
1.4 misho 4397: SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
4398: void(*)(void*));
1.2 misho 4399: SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
4400: SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
4401: SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
4402: SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
1.4 misho 4403: SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
1.2 misho 4404: SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
1.4 misho 4405: SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
4406: void(*)(void*), unsigned char encoding);
1.2 misho 4407: SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
1.4.2.2 misho 4408: SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*));
1.2 misho 4409: SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
1.4 misho 4410: SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
1.2 misho 4411:
4412: /*
4413: ** CAPI3REF: Number Of SQL Parameters
1.4 misho 4414: ** METHOD: sqlite3_stmt
1.2 misho 4415: **
4416: ** ^This routine can be used to find the number of [SQL parameters]
4417: ** in a [prepared statement]. SQL parameters are tokens of the
4418: ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
4419: ** placeholders for values that are [sqlite3_bind_blob | bound]
4420: ** to the parameters at a later time.
4421: **
4422: ** ^(This routine actually returns the index of the largest (rightmost)
4423: ** parameter. For all forms except ?NNN, this will correspond to the
4424: ** number of unique parameters. If parameters of the ?NNN form are used,
4425: ** there may be gaps in the list.)^
4426: **
4427: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
4428: ** [sqlite3_bind_parameter_name()], and
4429: ** [sqlite3_bind_parameter_index()].
4430: */
4431: SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
4432:
4433: /*
4434: ** CAPI3REF: Name Of A Host Parameter
1.4 misho 4435: ** METHOD: sqlite3_stmt
1.2 misho 4436: **
4437: ** ^The sqlite3_bind_parameter_name(P,N) interface returns
4438: ** the name of the N-th [SQL parameter] in the [prepared statement] P.
4439: ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
4440: ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
4441: ** respectively.
4442: ** In other words, the initial ":" or "$" or "@" or "?"
4443: ** is included as part of the name.)^
4444: ** ^Parameters of the form "?" without a following integer have no name
4445: ** and are referred to as "nameless" or "anonymous parameters".
4446: **
4447: ** ^The first host parameter has an index of 1, not 0.
4448: **
4449: ** ^If the value N is out of range or if the N-th parameter is
4450: ** nameless, then NULL is returned. ^The returned string is
4451: ** always in UTF-8 encoding even if the named parameter was
1.4.2.2 misho 4452: ** originally specified as UTF-16 in [sqlite3_prepare16()],
4453: ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
1.2 misho 4454: **
4455: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
4456: ** [sqlite3_bind_parameter_count()], and
4457: ** [sqlite3_bind_parameter_index()].
4458: */
4459: SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
4460:
4461: /*
4462: ** CAPI3REF: Index Of A Parameter With A Given Name
1.4 misho 4463: ** METHOD: sqlite3_stmt
1.2 misho 4464: **
4465: ** ^Return the index of an SQL parameter given its name. ^The
4466: ** index value returned is suitable for use as the second
4467: ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
4468: ** is returned if no matching parameter is found. ^The parameter
4469: ** name must be given in UTF-8 even if the original statement
1.4.2.2 misho 4470: ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or
4471: ** [sqlite3_prepare16_v3()].
1.2 misho 4472: **
4473: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
4474: ** [sqlite3_bind_parameter_count()], and
1.4 misho 4475: ** [sqlite3_bind_parameter_name()].
1.2 misho 4476: */
4477: SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
4478:
4479: /*
4480: ** CAPI3REF: Reset All Bindings On A Prepared Statement
1.4 misho 4481: ** METHOD: sqlite3_stmt
1.2 misho 4482: **
4483: ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
4484: ** the [sqlite3_bind_blob | bindings] on a [prepared statement].
4485: ** ^Use this routine to reset all host parameters to NULL.
4486: */
4487: SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
4488:
4489: /*
4490: ** CAPI3REF: Number Of Columns In A Result Set
1.4 misho 4491: ** METHOD: sqlite3_stmt
1.2 misho 4492: **
4493: ** ^Return the number of columns in the result set returned by the
1.4.2.3 ! misho 4494: ** [prepared statement]. ^If this routine returns 0, that means the
1.4.2.1 misho 4495: ** [prepared statement] returns no data (for example an [UPDATE]).
4496: ** ^However, just because this routine returns a positive number does not
4497: ** mean that one or more rows of data will be returned. ^A SELECT statement
4498: ** will always have a positive sqlite3_column_count() but depending on the
4499: ** WHERE clause constraints and the table content, it might return no rows.
1.2 misho 4500: **
4501: ** See also: [sqlite3_data_count()]
4502: */
4503: SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
4504:
4505: /*
4506: ** CAPI3REF: Column Names In A Result Set
1.4 misho 4507: ** METHOD: sqlite3_stmt
1.2 misho 4508: **
4509: ** ^These routines return the name assigned to a particular column
4510: ** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
4511: ** interface returns a pointer to a zero-terminated UTF-8 string
4512: ** and sqlite3_column_name16() returns a pointer to a zero-terminated
4513: ** UTF-16 string. ^The first parameter is the [prepared statement]
4514: ** that implements the [SELECT] statement. ^The second parameter is the
4515: ** column number. ^The leftmost column is number 0.
4516: **
4517: ** ^The returned string pointer is valid until either the [prepared statement]
4518: ** is destroyed by [sqlite3_finalize()] or until the statement is automatically
4519: ** reprepared by the first call to [sqlite3_step()] for a particular run
4520: ** or until the next call to
4521: ** sqlite3_column_name() or sqlite3_column_name16() on the same column.
4522: **
4523: ** ^If sqlite3_malloc() fails during the processing of either routine
4524: ** (for example during a conversion from UTF-8 to UTF-16) then a
4525: ** NULL pointer is returned.
4526: **
4527: ** ^The name of a result column is the value of the "AS" clause for
4528: ** that column, if there is an AS clause. If there is no AS clause
4529: ** then the name of the column is unspecified and may change from
4530: ** one release of SQLite to the next.
4531: */
4532: SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
4533: SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
4534:
4535: /*
4536: ** CAPI3REF: Source Of Data In A Query Result
1.4 misho 4537: ** METHOD: sqlite3_stmt
1.2 misho 4538: **
4539: ** ^These routines provide a means to determine the database, table, and
4540: ** table column that is the origin of a particular result column in
4541: ** [SELECT] statement.
4542: ** ^The name of the database or table or column can be returned as
4543: ** either a UTF-8 or UTF-16 string. ^The _database_ routines return
4544: ** the database name, the _table_ routines return the table name, and
4545: ** the origin_ routines return the column name.
4546: ** ^The returned string is valid until the [prepared statement] is destroyed
4547: ** using [sqlite3_finalize()] or until the statement is automatically
4548: ** reprepared by the first call to [sqlite3_step()] for a particular run
4549: ** or until the same information is requested
4550: ** again in a different encoding.
4551: **
4552: ** ^The names returned are the original un-aliased names of the
4553: ** database, table, and column.
4554: **
4555: ** ^The first argument to these interfaces is a [prepared statement].
4556: ** ^These functions return information about the Nth result column returned by
4557: ** the statement, where N is the second function argument.
4558: ** ^The left-most column is column 0 for these routines.
4559: **
4560: ** ^If the Nth column returned by the statement is an expression or
4561: ** subquery and is not a column value, then all of these functions return
1.4.2.3 ! misho 4562: ** NULL. ^These routines might also return NULL if a memory allocation error
1.2 misho 4563: ** occurs. ^Otherwise, they return the name of the attached database, table,
4564: ** or column that query result column was extracted from.
4565: **
4566: ** ^As with all other SQLite APIs, those whose names end with "16" return
4567: ** UTF-16 encoded strings and the other functions return UTF-8.
4568: **
4569: ** ^These APIs are only available if the library was compiled with the
4570: ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
4571: **
4572: ** If two or more threads call one or more
4573: ** [sqlite3_column_database_name | column metadata interfaces]
4574: ** for the same [prepared statement] and result column
4575: ** at the same time then the results are undefined.
4576: */
4577: SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
4578: SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
4579: SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
4580: SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
4581: SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
4582: SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
4583:
4584: /*
4585: ** CAPI3REF: Declared Datatype Of A Query Result
1.4 misho 4586: ** METHOD: sqlite3_stmt
1.2 misho 4587: **
4588: ** ^(The first parameter is a [prepared statement].
4589: ** If this statement is a [SELECT] statement and the Nth column of the
4590: ** returned result set of that [SELECT] is a table column (not an
4591: ** expression or subquery) then the declared type of the table
4592: ** column is returned.)^ ^If the Nth column of the result set is an
4593: ** expression or subquery, then a NULL pointer is returned.
4594: ** ^The returned string is always UTF-8 encoded.
4595: **
4596: ** ^(For example, given the database schema:
4597: **
4598: ** CREATE TABLE t1(c1 VARIANT);
4599: **
4600: ** and the following statement to be compiled:
4601: **
4602: ** SELECT c1 + 1, c1 FROM t1;
4603: **
4604: ** this routine would return the string "VARIANT" for the second result
4605: ** column (i==1), and a NULL pointer for the first result column (i==0).)^
4606: **
4607: ** ^SQLite uses dynamic run-time typing. ^So just because a column
4608: ** is declared to contain a particular type does not mean that the
4609: ** data stored in that column is of the declared type. SQLite is
4610: ** strongly typed, but the typing is dynamic not static. ^Type
4611: ** is associated with individual values, not with the containers
4612: ** used to hold those values.
4613: */
4614: SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
4615: SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
4616:
4617: /*
4618: ** CAPI3REF: Evaluate An SQL Statement
1.4 misho 4619: ** METHOD: sqlite3_stmt
1.2 misho 4620: **
1.4.2.2 misho 4621: ** After a [prepared statement] has been prepared using any of
4622: ** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()],
4623: ** or [sqlite3_prepare16_v3()] or one of the legacy
1.2 misho 4624: ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
4625: ** must be called one or more times to evaluate the statement.
4626: **
4627: ** The details of the behavior of the sqlite3_step() interface depend
1.4.2.2 misho 4628: ** on whether the statement was prepared using the newer "vX" interfaces
4629: ** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()],
4630: ** [sqlite3_prepare16_v2()] or the older legacy
4631: ** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
4632: ** new "vX" interface is recommended for new applications but the legacy
1.2 misho 4633: ** interface will continue to be supported.
4634: **
4635: ** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
4636: ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
4637: ** ^With the "v2" interface, any of the other [result codes] or
4638: ** [extended result codes] might be returned as well.
4639: **
4640: ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
4641: ** database locks it needs to do its job. ^If the statement is a [COMMIT]
4642: ** or occurs outside of an explicit transaction, then you can retry the
4643: ** statement. If the statement is not a [COMMIT] and occurs within an
4644: ** explicit transaction then you should rollback the transaction before
4645: ** continuing.
4646: **
4647: ** ^[SQLITE_DONE] means that the statement has finished executing
4648: ** successfully. sqlite3_step() should not be called again on this virtual
4649: ** machine without first calling [sqlite3_reset()] to reset the virtual
4650: ** machine back to its initial state.
4651: **
4652: ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
4653: ** is returned each time a new row of data is ready for processing by the
4654: ** caller. The values may be accessed using the [column access functions].
4655: ** sqlite3_step() is called again to retrieve the next row of data.
4656: **
4657: ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
4658: ** violation) has occurred. sqlite3_step() should not be called again on
4659: ** the VM. More information may be found by calling [sqlite3_errmsg()].
4660: ** ^With the legacy interface, a more specific error code (for example,
4661: ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
4662: ** can be obtained by calling [sqlite3_reset()] on the
4663: ** [prepared statement]. ^In the "v2" interface,
4664: ** the more specific error code is returned directly by sqlite3_step().
4665: **
4666: ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
4667: ** Perhaps it was called on a [prepared statement] that has
4668: ** already been [sqlite3_finalize | finalized] or on one that had
4669: ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
4670: ** be the case that the same database connection is being used by two or
4671: ** more threads at the same moment in time.
4672: **
4673: ** For all versions of SQLite up to and including 3.6.23.1, a call to
4674: ** [sqlite3_reset()] was required after sqlite3_step() returned anything
4675: ** other than [SQLITE_ROW] before any subsequent invocation of
1.4.2.3 ! misho 4676: ** sqlite3_step(). Failure to reset the prepared statement using
1.2 misho 4677: ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
1.4.2.1 misho 4678: ** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1],
4679: ** sqlite3_step() began
1.2 misho 4680: ** calling [sqlite3_reset()] automatically in this circumstance rather
4681: ** than returning [SQLITE_MISUSE]. This is not considered a compatibility
4682: ** break because any application that ever receives an SQLITE_MISUSE error
4683: ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option
4684: ** can be used to restore the legacy behavior.
4685: **
4686: ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
4687: ** API always returns a generic error code, [SQLITE_ERROR], following any
4688: ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
4689: ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
4690: ** specific [error codes] that better describes the error.
4691: ** We admit that this is a goofy design. The problem has been fixed
4692: ** with the "v2" interface. If you prepare all of your SQL statements
1.4.2.2 misho 4693: ** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()]
4694: ** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead
1.2 misho 4695: ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
4696: ** then the more specific [error codes] are returned directly
1.4.2.2 misho 4697: ** by sqlite3_step(). The use of the "vX" interfaces is recommended.
1.2 misho 4698: */
4699: SQLITE_API int sqlite3_step(sqlite3_stmt*);
4700:
4701: /*
4702: ** CAPI3REF: Number of columns in a result set
1.4 misho 4703: ** METHOD: sqlite3_stmt
1.2 misho 4704: **
4705: ** ^The sqlite3_data_count(P) interface returns the number of columns in the
4706: ** current row of the result set of [prepared statement] P.
4707: ** ^If prepared statement P does not have results ready to return
1.4.2.3 ! misho 4708: ** (via calls to the [sqlite3_column_int | sqlite3_column()] family of
1.2 misho 4709: ** interfaces) then sqlite3_data_count(P) returns 0.
4710: ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
4711: ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
4712: ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)
4713: ** will return non-zero if previous call to [sqlite3_step](P) returned
4714: ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
4715: ** where it always returns zero since each step of that multi-step
4716: ** pragma returns 0 columns of data.
4717: **
4718: ** See also: [sqlite3_column_count()]
4719: */
4720: SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
4721:
4722: /*
4723: ** CAPI3REF: Fundamental Datatypes
4724: ** KEYWORDS: SQLITE_TEXT
4725: **
4726: ** ^(Every value in SQLite has one of five fundamental datatypes:
4727: **
4728: ** <ul>
4729: ** <li> 64-bit signed integer
4730: ** <li> 64-bit IEEE floating point number
4731: ** <li> string
4732: ** <li> BLOB
4733: ** <li> NULL
4734: ** </ul>)^
4735: **
4736: ** These constants are codes for each of those types.
4737: **
4738: ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
4739: ** for a completely different meaning. Software that links against both
4740: ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
4741: ** SQLITE_TEXT.
4742: */
4743: #define SQLITE_INTEGER 1
4744: #define SQLITE_FLOAT 2
4745: #define SQLITE_BLOB 4
4746: #define SQLITE_NULL 5
4747: #ifdef SQLITE_TEXT
4748: # undef SQLITE_TEXT
4749: #else
4750: # define SQLITE_TEXT 3
4751: #endif
4752: #define SQLITE3_TEXT 3
4753:
4754: /*
4755: ** CAPI3REF: Result Values From A Query
4756: ** KEYWORDS: {column access functions}
1.4 misho 4757: ** METHOD: sqlite3_stmt
1.2 misho 4758: **
1.4.2.2 misho 4759: ** <b>Summary:</b>
4760: ** <blockquote><table border=0 cellpadding=0 cellspacing=0>
4761: ** <tr><td><b>sqlite3_column_blob</b><td>→<td>BLOB result
4762: ** <tr><td><b>sqlite3_column_double</b><td>→<td>REAL result
4763: ** <tr><td><b>sqlite3_column_int</b><td>→<td>32-bit INTEGER result
4764: ** <tr><td><b>sqlite3_column_int64</b><td>→<td>64-bit INTEGER result
4765: ** <tr><td><b>sqlite3_column_text</b><td>→<td>UTF-8 TEXT result
4766: ** <tr><td><b>sqlite3_column_text16</b><td>→<td>UTF-16 TEXT result
1.4.2.3 ! misho 4767: ** <tr><td><b>sqlite3_column_value</b><td>→<td>The result as an
1.4.2.2 misho 4768: ** [sqlite3_value|unprotected sqlite3_value] object.
4769: ** <tr><td> <td> <td>
4770: ** <tr><td><b>sqlite3_column_bytes</b><td>→<td>Size of a BLOB
4771: ** or a UTF-8 TEXT result in bytes
4772: ** <tr><td><b>sqlite3_column_bytes16 </b>
4773: ** <td>→ <td>Size of UTF-16
4774: ** TEXT in bytes
4775: ** <tr><td><b>sqlite3_column_type</b><td>→<td>Default
4776: ** datatype of the result
4777: ** </table></blockquote>
4778: **
4779: ** <b>Details:</b>
4780: **
1.2 misho 4781: ** ^These routines return information about a single column of the current
4782: ** result row of a query. ^In every case the first argument is a pointer
4783: ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
4784: ** that was returned from [sqlite3_prepare_v2()] or one of its variants)
4785: ** and the second argument is the index of the column for which information
4786: ** should be returned. ^The leftmost column of the result set has the index 0.
4787: ** ^The number of columns in the result can be determined using
4788: ** [sqlite3_column_count()].
4789: **
4790: ** If the SQL statement does not currently point to a valid row, or if the
4791: ** column index is out of range, the result is undefined.
4792: ** These routines may only be called when the most recent call to
4793: ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
4794: ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
4795: ** If any of these routines are called after [sqlite3_reset()] or
4796: ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
4797: ** something other than [SQLITE_ROW], the results are undefined.
4798: ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
4799: ** are called from a different thread while any of these routines
4800: ** are pending, then the results are undefined.
4801: **
1.4.2.2 misho 4802: ** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16)
4803: ** each return the value of a result column in a specific data format. If
4804: ** the result column is not initially in the requested format (for example,
4805: ** if the query returns an integer but the sqlite3_column_text() interface
4806: ** is used to extract the value) then an automatic type conversion is performed.
4807: **
1.2 misho 4808: ** ^The sqlite3_column_type() routine returns the
4809: ** [SQLITE_INTEGER | datatype code] for the initial data type
4810: ** of the result column. ^The returned value is one of [SQLITE_INTEGER],
1.4.2.2 misho 4811: ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].
4812: ** The return value of sqlite3_column_type() can be used to decide which
4813: ** of the first six interface should be used to extract the column value.
4814: ** The value returned by sqlite3_column_type() is only meaningful if no
1.4.2.3 ! misho 4815: ** automatic type conversions have occurred for the value in question.
1.4.2.2 misho 4816: ** After a type conversion, the result of calling sqlite3_column_type()
4817: ** is undefined, though harmless. Future
1.2 misho 4818: ** versions of SQLite may change the behavior of sqlite3_column_type()
4819: ** following a type conversion.
4820: **
1.4.2.2 misho 4821: ** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes()
4822: ** or sqlite3_column_bytes16() interfaces can be used to determine the size
4823: ** of that BLOB or string.
4824: **
1.2 misho 4825: ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
4826: ** routine returns the number of bytes in that BLOB or string.
4827: ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
4828: ** the string to UTF-8 and then returns the number of bytes.
4829: ** ^If the result is a numeric value then sqlite3_column_bytes() uses
4830: ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
4831: ** the number of bytes in that string.
4832: ** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
4833: **
4834: ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
4835: ** routine returns the number of bytes in that BLOB or string.
4836: ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
4837: ** the string to UTF-16 and then returns the number of bytes.
4838: ** ^If the result is a numeric value then sqlite3_column_bytes16() uses
4839: ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
4840: ** the number of bytes in that string.
4841: ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
4842: **
1.4.2.3 ! misho 4843: ** ^The values returned by [sqlite3_column_bytes()] and
1.2 misho 4844: ** [sqlite3_column_bytes16()] do not include the zero terminators at the end
4845: ** of the string. ^For clarity: the values returned by
4846: ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
4847: ** bytes in the string, not the number of characters.
4848: **
4849: ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
4850: ** even empty strings, are always zero-terminated. ^The return
4851: ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
4852: **
1.4 misho 4853: ** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
4854: ** [unprotected sqlite3_value] object. In a multithreaded environment,
4855: ** an unprotected sqlite3_value object may only be used safely with
4856: ** [sqlite3_bind_value()] and [sqlite3_result_value()].
1.2 misho 4857: ** If the [unprotected sqlite3_value] object returned by
4858: ** [sqlite3_column_value()] is used in any other way, including calls
4859: ** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
1.4 misho 4860: ** or [sqlite3_value_bytes()], the behavior is not threadsafe.
1.4.2.2 misho 4861: ** Hence, the sqlite3_column_value() interface
1.4.2.3 ! misho 4862: ** is normally only useful within the implementation of
1.4.2.2 misho 4863: ** [application-defined SQL functions] or [virtual tables], not within
4864: ** top-level application code.
1.2 misho 4865: **
1.4.2.2 misho 4866: ** The these routines may attempt to convert the datatype of the result.
4867: ** ^For example, if the internal representation is FLOAT and a text result
1.2 misho 4868: ** is requested, [sqlite3_snprintf()] is used internally to perform the
4869: ** conversion automatically. ^(The following table details the conversions
4870: ** that are applied:
4871: **
4872: ** <blockquote>
4873: ** <table border="1">
4874: ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
4875: **
4876: ** <tr><td> NULL <td> INTEGER <td> Result is 0
4877: ** <tr><td> NULL <td> FLOAT <td> Result is 0.0
1.4 misho 4878: ** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer
4879: ** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer
1.2 misho 4880: ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
4881: ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
4882: ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
1.4 misho 4883: ** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER
1.2 misho 4884: ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
1.4 misho 4885: ** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB
4886: ** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER
4887: ** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL
1.2 misho 4888: ** <tr><td> TEXT <td> BLOB <td> No change
1.4 misho 4889: ** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER
4890: ** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL
1.2 misho 4891: ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
4892: ** </table>
4893: ** </blockquote>)^
4894: **
4895: ** Note that when type conversions occur, pointers returned by prior
4896: ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
4897: ** sqlite3_column_text16() may be invalidated.
4898: ** Type conversions and pointer invalidations might occur
4899: ** in the following cases:
4900: **
4901: ** <ul>
4902: ** <li> The initial content is a BLOB and sqlite3_column_text() or
4903: ** sqlite3_column_text16() is called. A zero-terminator might
4904: ** need to be added to the string.</li>
4905: ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
4906: ** sqlite3_column_text16() is called. The content must be converted
4907: ** to UTF-16.</li>
4908: ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
4909: ** sqlite3_column_text() is called. The content must be converted
4910: ** to UTF-8.</li>
4911: ** </ul>
4912: **
4913: ** ^Conversions between UTF-16be and UTF-16le are always done in place and do
4914: ** not invalidate a prior pointer, though of course the content of the buffer
4915: ** that the prior pointer references will have been modified. Other kinds
4916: ** of conversion are done in place when it is possible, but sometimes they
4917: ** are not possible and in those cases prior pointers are invalidated.
4918: **
1.4 misho 4919: ** The safest policy is to invoke these routines
1.2 misho 4920: ** in one of the following ways:
4921: **
4922: ** <ul>
4923: ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
4924: ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
4925: ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
4926: ** </ul>
4927: **
4928: ** In other words, you should call sqlite3_column_text(),
4929: ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
4930: ** into the desired format, then invoke sqlite3_column_bytes() or
4931: ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
4932: ** to sqlite3_column_text() or sqlite3_column_blob() with calls to
4933: ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
4934: ** with calls to sqlite3_column_bytes().
4935: **
4936: ** ^The pointers returned are valid until a type conversion occurs as
4937: ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
4938: ** [sqlite3_finalize()] is called. ^The memory space used to hold strings
1.4.2.2 misho 4939: ** and BLOBs is freed automatically. Do not pass the pointers returned
1.4 misho 4940: ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
1.2 misho 4941: ** [sqlite3_free()].
4942: **
1.4.2.2 misho 4943: ** As long as the input parameters are correct, these routines will only
4944: ** fail if an out-of-memory error occurs during a format conversion.
4945: ** Only the following subset of interfaces are subject to out-of-memory
4946: ** errors:
4947: **
4948: ** <ul>
4949: ** <li> sqlite3_column_blob()
4950: ** <li> sqlite3_column_text()
4951: ** <li> sqlite3_column_text16()
4952: ** <li> sqlite3_column_bytes()
4953: ** <li> sqlite3_column_bytes16()
4954: ** </ul>
4955: **
4956: ** If an out-of-memory error occurs, then the return value from these
4957: ** routines is the same as if the column had contained an SQL NULL value.
4958: ** Valid SQL NULL returns can be distinguished from out-of-memory errors
4959: ** by invoking the [sqlite3_errcode()] immediately after the suspect
4960: ** return value is obtained and before any
4961: ** other SQLite interface is called on the same [database connection].
1.2 misho 4962: */
4963: SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
4964: SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
4965: SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
4966: SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
4967: SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
4968: SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
4969: SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
1.4.2.2 misho 4970: SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
4971: SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
4972: SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
1.2 misho 4973:
4974: /*
4975: ** CAPI3REF: Destroy A Prepared Statement Object
1.4 misho 4976: ** DESTRUCTOR: sqlite3_stmt
1.2 misho 4977: **
4978: ** ^The sqlite3_finalize() function is called to delete a [prepared statement].
4979: ** ^If the most recent evaluation of the statement encountered no errors
4980: ** or if the statement is never been evaluated, then sqlite3_finalize() returns
4981: ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then
4982: ** sqlite3_finalize(S) returns the appropriate [error code] or
4983: ** [extended error code].
4984: **
4985: ** ^The sqlite3_finalize(S) routine can be called at any point during
4986: ** the life cycle of [prepared statement] S:
4987: ** before statement S is ever evaluated, after
4988: ** one or more calls to [sqlite3_reset()], or after any call
4989: ** to [sqlite3_step()] regardless of whether or not the statement has
4990: ** completed execution.
4991: **
4992: ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
4993: **
4994: ** The application must finalize every [prepared statement] in order to avoid
4995: ** resource leaks. It is a grievous error for the application to try to use
4996: ** a prepared statement after it has been finalized. Any use of a prepared
4997: ** statement after it has been finalized can result in undefined and
4998: ** undesirable behavior such as segfaults and heap corruption.
4999: */
5000: SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
5001:
5002: /*
5003: ** CAPI3REF: Reset A Prepared Statement Object
1.4 misho 5004: ** METHOD: sqlite3_stmt
1.2 misho 5005: **
5006: ** The sqlite3_reset() function is called to reset a [prepared statement]
5007: ** object back to its initial state, ready to be re-executed.
5008: ** ^Any SQL statement variables that had values bound to them using
5009: ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
5010: ** Use [sqlite3_clear_bindings()] to reset the bindings.
5011: **
5012: ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
5013: ** back to the beginning of its program.
5014: **
5015: ** ^If the most recent call to [sqlite3_step(S)] for the
5016: ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
5017: ** or if [sqlite3_step(S)] has never before been called on S,
5018: ** then [sqlite3_reset(S)] returns [SQLITE_OK].
5019: **
5020: ** ^If the most recent call to [sqlite3_step(S)] for the
5021: ** [prepared statement] S indicated an error, then
5022: ** [sqlite3_reset(S)] returns an appropriate [error code].
5023: **
5024: ** ^The [sqlite3_reset(S)] interface does not change the values
5025: ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
5026: */
5027: SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
5028:
5029: /*
5030: ** CAPI3REF: Create Or Redefine SQL Functions
5031: ** KEYWORDS: {function creation routines}
1.4 misho 5032: ** METHOD: sqlite3
1.2 misho 5033: **
5034: ** ^These functions (collectively known as "function creation routines")
5035: ** are used to add SQL functions or aggregates or to redefine the behavior
1.4.2.2 misho 5036: ** of existing SQL functions or aggregates. The only differences between
1.4.2.3 ! misho 5037: ** the three "sqlite3_create_function*" routines are the text encoding
! 5038: ** expected for the second parameter (the name of the function being
1.4.2.2 misho 5039: ** created) and the presence or absence of a destructor callback for
5040: ** the application data pointer. Function sqlite3_create_window_function()
5041: ** is similar, but allows the user to supply the extra callback functions
5042: ** needed by [aggregate window functions].
1.2 misho 5043: **
5044: ** ^The first parameter is the [database connection] to which the SQL
5045: ** function is to be added. ^If an application uses more than one database
5046: ** connection then application-defined SQL functions must be added
5047: ** to each database connection separately.
5048: **
5049: ** ^The second parameter is the name of the SQL function to be created or
5050: ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8
5051: ** representation, exclusive of the zero-terminator. ^Note that the name
1.4.2.3 ! misho 5052: ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
1.2 misho 5053: ** ^Any attempt to create a function with a longer name
5054: ** will result in [SQLITE_MISUSE] being returned.
5055: **
5056: ** ^The third parameter (nArg)
5057: ** is the number of arguments that the SQL function or
5058: ** aggregate takes. ^If this parameter is -1, then the SQL function or
5059: ** aggregate may take any number of arguments between 0 and the limit
5060: ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
5061: ** parameter is less than -1 or greater than 127 then the behavior is
5062: ** undefined.
5063: **
5064: ** ^The fourth parameter, eTextRep, specifies what
5065: ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
1.4 misho 5066: ** its parameters. The application should set this parameter to
1.4.2.3 ! misho 5067: ** [SQLITE_UTF16LE] if the function implementation invokes
1.4 misho 5068: ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
5069: ** implementation invokes [sqlite3_value_text16be()] on an input, or
5070: ** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
5071: ** otherwise. ^The same SQL function may be registered multiple times using
5072: ** different preferred text encodings, with different implementations for
5073: ** each encoding.
1.2 misho 5074: ** ^When multiple implementations of the same function are available, SQLite
5075: ** will pick the one that involves the least amount of data conversion.
1.4 misho 5076: **
5077: ** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
5078: ** to signal that the function will always return the same result given
5079: ** the same inputs within a single SQL statement. Most SQL functions are
5080: ** deterministic. The built-in [random()] SQL function is an example of a
5081: ** function that is not deterministic. The SQLite query planner is able to
5082: ** perform additional optimizations on deterministic functions, so use
5083: ** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
1.2 misho 5084: **
1.4.2.3 ! misho 5085: ** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY]
! 5086: ** flag, which if present prevents the function from being invoked from
! 5087: ** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions,
! 5088: ** index expressions, or the WHERE clause of partial indexes.
! 5089: **
! 5090: ** <span style="background-color:#ffff90;">
! 5091: ** For best security, the [SQLITE_DIRECTONLY] flag is recommended for
! 5092: ** all application-defined SQL functions that do not need to be
! 5093: ** used inside of triggers, view, CHECK constraints, or other elements of
! 5094: ** the database schema. This flags is especially recommended for SQL
! 5095: ** functions that have side effects or reveal internal application state.
! 5096: ** Without this flag, an attacker might be able to modify the schema of
! 5097: ** a database file to include invocations of the function with parameters
! 5098: ** chosen by the attacker, which the application will then execute when
! 5099: ** the database file is opened and read.
! 5100: ** </span>
! 5101: **
1.2 misho 5102: ** ^(The fifth parameter is an arbitrary pointer. The implementation of the
5103: ** function can gain access to this pointer using [sqlite3_user_data()].)^
5104: **
1.4.2.2 misho 5105: ** ^The sixth, seventh and eighth parameters passed to the three
5106: ** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are
1.2 misho 5107: ** pointers to C-language functions that implement the SQL function or
5108: ** aggregate. ^A scalar SQL function requires an implementation of the xFunc
5109: ** callback only; NULL pointers must be passed as the xStep and xFinal
5110: ** parameters. ^An aggregate SQL function requires an implementation of xStep
5111: ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
5112: ** SQL function or aggregate, pass NULL pointers for all three function
5113: ** callbacks.
5114: **
1.4.2.3 ! misho 5115: ** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue
1.4.2.2 misho 5116: ** and xInverse) passed to sqlite3_create_window_function are pointers to
5117: ** C-language callbacks that implement the new function. xStep and xFinal
5118: ** must both be non-NULL. xValue and xInverse may either both be NULL, in
1.4.2.3 ! misho 5119: ** which case a regular aggregate function is created, or must both be
1.4.2.2 misho 5120: ** non-NULL, in which case the new function may be used as either an aggregate
5121: ** or aggregate window function. More details regarding the implementation
1.4.2.3 ! misho 5122: ** of aggregate window functions are
1.4.2.2 misho 5123: ** [user-defined window functions|available here].
5124: **
5125: ** ^(If the final parameter to sqlite3_create_function_v2() or
5126: ** sqlite3_create_window_function() is not NULL, then it is destructor for
1.4.2.3 ! misho 5127: ** the application data pointer. The destructor is invoked when the function
! 5128: ** is deleted, either by being overloaded or when the database connection
! 5129: ** closes.)^ ^The destructor is also invoked if the call to
1.4.2.2 misho 5130: ** sqlite3_create_function_v2() fails. ^When the destructor callback is
5131: ** invoked, it is passed a single argument which is a copy of the application
5132: ** data pointer which was the fifth parameter to sqlite3_create_function_v2().
1.2 misho 5133: **
5134: ** ^It is permitted to register multiple implementations of the same
5135: ** functions with the same name but with either differing numbers of
5136: ** arguments or differing preferred text encodings. ^SQLite will use
5137: ** the implementation that most closely matches the way in which the
5138: ** SQL function is used. ^A function implementation with a non-negative
5139: ** nArg parameter is a better match than a function implementation with
5140: ** a negative nArg. ^A function where the preferred text encoding
5141: ** matches the database encoding is a better
1.4.2.3 ! misho 5142: ** match than a function where the encoding is different.
1.2 misho 5143: ** ^A function where the encoding difference is between UTF16le and UTF16be
5144: ** is a closer match than a function where the encoding difference is
5145: ** between UTF8 and UTF16.
5146: **
5147: ** ^Built-in functions may be overloaded by new application-defined functions.
5148: **
5149: ** ^An application-defined function is permitted to call other
5150: ** SQLite interfaces. However, such calls must not
5151: ** close the database connection nor finalize or reset the prepared
5152: ** statement in which the function is running.
5153: */
5154: SQLITE_API int sqlite3_create_function(
5155: sqlite3 *db,
5156: const char *zFunctionName,
5157: int nArg,
5158: int eTextRep,
5159: void *pApp,
5160: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5161: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5162: void (*xFinal)(sqlite3_context*)
5163: );
5164: SQLITE_API int sqlite3_create_function16(
5165: sqlite3 *db,
5166: const void *zFunctionName,
5167: int nArg,
5168: int eTextRep,
5169: void *pApp,
5170: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5171: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5172: void (*xFinal)(sqlite3_context*)
5173: );
5174: SQLITE_API int sqlite3_create_function_v2(
5175: sqlite3 *db,
5176: const char *zFunctionName,
5177: int nArg,
5178: int eTextRep,
5179: void *pApp,
5180: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5181: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5182: void (*xFinal)(sqlite3_context*),
5183: void(*xDestroy)(void*)
5184: );
1.4.2.2 misho 5185: SQLITE_API int sqlite3_create_window_function(
5186: sqlite3 *db,
5187: const char *zFunctionName,
5188: int nArg,
5189: int eTextRep,
5190: void *pApp,
5191: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5192: void (*xFinal)(sqlite3_context*),
5193: void (*xValue)(sqlite3_context*),
5194: void (*xInverse)(sqlite3_context*,int,sqlite3_value**),
5195: void(*xDestroy)(void*)
5196: );
1.2 misho 5197:
5198: /*
5199: ** CAPI3REF: Text Encodings
5200: **
5201: ** These constant define integer codes that represent the various
5202: ** text encodings supported by SQLite.
5203: */
1.4 misho 5204: #define SQLITE_UTF8 1 /* IMP: R-37514-35566 */
5205: #define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */
5206: #define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */
1.2 misho 5207: #define SQLITE_UTF16 4 /* Use native byte order */
1.4 misho 5208: #define SQLITE_ANY 5 /* Deprecated */
1.2 misho 5209: #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
5210:
5211: /*
1.4 misho 5212: ** CAPI3REF: Function Flags
5213: **
1.4.2.3 ! misho 5214: ** These constants may be ORed together with the
1.4 misho 5215: ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
5216: ** to [sqlite3_create_function()], [sqlite3_create_function16()], or
5217: ** [sqlite3_create_function_v2()].
1.4.2.3 ! misho 5218: **
! 5219: ** <dl>
! 5220: ** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd>
! 5221: ** The SQLITE_DETERMINISTIC flag means that the new function always gives
! 5222: ** the same output when the input parameters are the same.
! 5223: ** The [abs|abs() function] is deterministic, for example, but
! 5224: ** [randomblob|randomblob()] is not. Functions must
! 5225: ** be deterministic in order to be used in certain contexts such as
! 5226: ** with the WHERE clause of [partial indexes] or in [generated columns].
! 5227: ** SQLite might also optimize deterministic functions by factoring them
! 5228: ** out of inner loops.
! 5229: ** </dd>
! 5230: **
! 5231: ** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd>
! 5232: ** The SQLITE_DIRECTONLY flag means that the function may only be invoked
! 5233: ** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in
! 5234: ** schema structures such as [CHECK constraints], [DEFAULT clauses],
! 5235: ** [expression indexes], [partial indexes], or [generated columns].
! 5236: ** The SQLITE_DIRECTONLY flags is a security feature which is recommended
! 5237: ** for all [application-defined SQL functions], and especially for functions
! 5238: ** that have side-effects or that could potentially leak sensitive
! 5239: ** information.
! 5240: ** </dd>
! 5241: **
! 5242: ** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd>
! 5243: ** The SQLITE_INNOCUOUS flag means that the function is unlikely
! 5244: ** to cause problems even if misused. An innocuous function should have
! 5245: ** no side effects and should not depend on any values other than its
! 5246: ** input parameters. The [abs|abs() function] is an example of an
! 5247: ** innocuous function.
! 5248: ** The [load_extension() SQL function] is not innocuous because of its
! 5249: ** side effects.
! 5250: ** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not
! 5251: ** exactly the same. The [random|random() function] is an example of a
! 5252: ** function that is innocuous but not deterministic.
! 5253: ** <p>Some heightened security settings
! 5254: ** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF])
! 5255: ** disable the use of SQL functions inside views and triggers and in
! 5256: ** schema structures such as [CHECK constraints], [DEFAULT clauses],
! 5257: ** [expression indexes], [partial indexes], and [generated columns] unless
! 5258: ** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions
! 5259: ** are innocuous. Developers are advised to avoid using the
! 5260: ** SQLITE_INNOCUOUS flag for application-defined functions unless the
! 5261: ** function has been carefully audited and found to be free of potentially
! 5262: ** security-adverse side-effects and information-leaks.
! 5263: ** </dd>
! 5264: **
! 5265: ** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd>
! 5266: ** The SQLITE_SUBTYPE flag indicates to SQLite that a function may call
! 5267: ** [sqlite3_value_subtype()] to inspect the sub-types of its arguments.
! 5268: ** Specifying this flag makes no difference for scalar or aggregate user
! 5269: ** functions. However, if it is not specified for a user-defined window
! 5270: ** function, then any sub-types belonging to arguments passed to the window
! 5271: ** function may be discarded before the window function is called (i.e.
! 5272: ** sqlite3_value_subtype() will always return 0).
! 5273: ** </dd>
! 5274: ** </dl>
1.4 misho 5275: */
1.4.2.3 ! misho 5276: #define SQLITE_DETERMINISTIC 0x000000800
! 5277: #define SQLITE_DIRECTONLY 0x000080000
! 5278: #define SQLITE_SUBTYPE 0x000100000
! 5279: #define SQLITE_INNOCUOUS 0x000200000
1.4 misho 5280:
5281: /*
1.2 misho 5282: ** CAPI3REF: Deprecated Functions
5283: ** DEPRECATED
5284: **
5285: ** These functions are [deprecated]. In order to maintain
1.4.2.3 ! misho 5286: ** backwards compatibility with older code, these functions continue
1.2 misho 5287: ** to be supported. However, new applications should avoid
1.4 misho 5288: ** the use of these functions. To encourage programmers to avoid
5289: ** these functions, we will not explain what they do.
1.2 misho 5290: */
5291: #ifndef SQLITE_OMIT_DEPRECATED
5292: SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
5293: SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
5294: SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
5295: SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
5296: SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
1.4 misho 5297: SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
5298: void*,sqlite3_int64);
1.2 misho 5299: #endif
5300:
5301: /*
1.4 misho 5302: ** CAPI3REF: Obtaining SQL Values
5303: ** METHOD: sqlite3_value
1.2 misho 5304: **
1.4.2.2 misho 5305: ** <b>Summary:</b>
5306: ** <blockquote><table border=0 cellpadding=0 cellspacing=0>
5307: ** <tr><td><b>sqlite3_value_blob</b><td>→<td>BLOB value
5308: ** <tr><td><b>sqlite3_value_double</b><td>→<td>REAL value
5309: ** <tr><td><b>sqlite3_value_int</b><td>→<td>32-bit INTEGER value
5310: ** <tr><td><b>sqlite3_value_int64</b><td>→<td>64-bit INTEGER value
5311: ** <tr><td><b>sqlite3_value_pointer</b><td>→<td>Pointer value
5312: ** <tr><td><b>sqlite3_value_text</b><td>→<td>UTF-8 TEXT value
5313: ** <tr><td><b>sqlite3_value_text16</b><td>→<td>UTF-16 TEXT value in
5314: ** the native byteorder
5315: ** <tr><td><b>sqlite3_value_text16be</b><td>→<td>UTF-16be TEXT value
5316: ** <tr><td><b>sqlite3_value_text16le</b><td>→<td>UTF-16le TEXT value
5317: ** <tr><td> <td> <td>
5318: ** <tr><td><b>sqlite3_value_bytes</b><td>→<td>Size of a BLOB
5319: ** or a UTF-8 TEXT in bytes
5320: ** <tr><td><b>sqlite3_value_bytes16 </b>
5321: ** <td>→ <td>Size of UTF-16
5322: ** TEXT in bytes
5323: ** <tr><td><b>sqlite3_value_type</b><td>→<td>Default
5324: ** datatype of the value
5325: ** <tr><td><b>sqlite3_value_numeric_type </b>
5326: ** <td>→ <td>Best numeric datatype of the value
5327: ** <tr><td><b>sqlite3_value_nochange </b>
5328: ** <td>→ <td>True if the column is unchanged in an UPDATE
5329: ** against a virtual table.
5330: ** <tr><td><b>sqlite3_value_frombind </b>
5331: ** <td>→ <td>True if value originated from a [bound parameter]
5332: ** </table></blockquote>
5333: **
5334: ** <b>Details:</b>
5335: **
5336: ** These routines extract type, size, and content information from
5337: ** [protected sqlite3_value] objects. Protected sqlite3_value objects
1.4.2.3 ! misho 5338: ** are used to pass parameter information into the functions that
! 5339: ** implement [application-defined SQL functions] and [virtual tables].
1.2 misho 5340: **
5341: ** These routines work only with [protected sqlite3_value] objects.
5342: ** Any attempt to use these routines on an [unprotected sqlite3_value]
1.4.2.2 misho 5343: ** is not threadsafe.
1.2 misho 5344: **
5345: ** ^These routines work just like the corresponding [column access functions]
1.4 misho 5346: ** except that these routines take a single [protected sqlite3_value] object
1.2 misho 5347: ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
5348: **
5349: ** ^The sqlite3_value_text16() interface extracts a UTF-16 string
5350: ** in the native byte-order of the host machine. ^The
5351: ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
5352: ** extract UTF-16 strings as big-endian and little-endian respectively.
5353: **
1.4.2.3 ! misho 5354: ** ^If [sqlite3_value] object V was initialized
1.4.2.2 misho 5355: ** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)]
5356: ** and if X and Y are strings that compare equal according to strcmp(X,Y),
5357: ** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise,
1.4.2.3 ! misho 5358: ** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer()
1.4.2.2 misho 5359: ** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
5360: **
5361: ** ^(The sqlite3_value_type(V) interface returns the
5362: ** [SQLITE_INTEGER | datatype code] for the initial datatype of the
5363: ** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER],
5364: ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^
5365: ** Other interfaces might change the datatype for an sqlite3_value object.
5366: ** For example, if the datatype is initially SQLITE_INTEGER and
5367: ** sqlite3_value_text(V) is called to extract a text value for that
5368: ** integer, then subsequent calls to sqlite3_value_type(V) might return
5369: ** SQLITE_TEXT. Whether or not a persistent internal datatype conversion
5370: ** occurs is undefined and may change from one release of SQLite to the next.
5371: **
1.2 misho 5372: ** ^(The sqlite3_value_numeric_type() interface attempts to apply
5373: ** numeric affinity to the value. This means that an attempt is
5374: ** made to convert the value to an integer or floating point. If
5375: ** such a conversion is possible without loss of information (in other
5376: ** words, if the value is a string that looks like a number)
5377: ** then the conversion is performed. Otherwise no conversion occurs.
5378: ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
5379: **
1.4.2.2 misho 5380: ** ^Within the [xUpdate] method of a [virtual table], the
5381: ** sqlite3_value_nochange(X) interface returns true if and only if
5382: ** the column corresponding to X is unchanged by the UPDATE operation
5383: ** that the xUpdate method call was invoked to implement and if
5384: ** and the prior [xColumn] method call that was invoked to extracted
5385: ** the value for that column returned without setting a result (probably
5386: ** because it queried [sqlite3_vtab_nochange()] and found that the column
5387: ** was unchanging). ^Within an [xUpdate] method, any value for which
5388: ** sqlite3_value_nochange(X) is true will in all other respects appear
5389: ** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other
5390: ** than within an [xUpdate] method call for an UPDATE statement, then
5391: ** the return value is arbitrary and meaningless.
5392: **
5393: ** ^The sqlite3_value_frombind(X) interface returns non-zero if the
5394: ** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()]
5395: ** interfaces. ^If X comes from an SQL literal value, or a table column,
1.4.2.3 ! misho 5396: ** or an expression, then sqlite3_value_frombind(X) returns zero.
1.4.2.2 misho 5397: **
1.2 misho 5398: ** Please pay particular attention to the fact that the pointer returned
5399: ** from [sqlite3_value_blob()], [sqlite3_value_text()], or
5400: ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
5401: ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
5402: ** or [sqlite3_value_text16()].
5403: **
5404: ** These routines must be called from the same thread as
5405: ** the SQL function that supplied the [sqlite3_value*] parameters.
1.4.2.2 misho 5406: **
5407: ** As long as the input parameter is correct, these routines can only
5408: ** fail if an out-of-memory error occurs during a format conversion.
5409: ** Only the following subset of interfaces are subject to out-of-memory
5410: ** errors:
5411: **
5412: ** <ul>
5413: ** <li> sqlite3_value_blob()
5414: ** <li> sqlite3_value_text()
5415: ** <li> sqlite3_value_text16()
5416: ** <li> sqlite3_value_text16le()
5417: ** <li> sqlite3_value_text16be()
5418: ** <li> sqlite3_value_bytes()
5419: ** <li> sqlite3_value_bytes16()
5420: ** </ul>
5421: **
5422: ** If an out-of-memory error occurs, then the return value from these
5423: ** routines is the same as if the column had contained an SQL NULL value.
5424: ** Valid SQL NULL returns can be distinguished from out-of-memory errors
5425: ** by invoking the [sqlite3_errcode()] immediately after the suspect
5426: ** return value is obtained and before any
5427: ** other SQLite interface is called on the same [database connection].
1.2 misho 5428: */
5429: SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
5430: SQLITE_API double sqlite3_value_double(sqlite3_value*);
5431: SQLITE_API int sqlite3_value_int(sqlite3_value*);
5432: SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
1.4.2.2 misho 5433: SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*);
1.2 misho 5434: SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
5435: SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
5436: SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
5437: SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
1.4.2.2 misho 5438: SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
5439: SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
1.2 misho 5440: SQLITE_API int sqlite3_value_type(sqlite3_value*);
5441: SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
1.4.2.2 misho 5442: SQLITE_API int sqlite3_value_nochange(sqlite3_value*);
5443: SQLITE_API int sqlite3_value_frombind(sqlite3_value*);
1.2 misho 5444:
5445: /*
1.4 misho 5446: ** CAPI3REF: Finding The Subtype Of SQL Values
5447: ** METHOD: sqlite3_value
5448: **
5449: ** The sqlite3_value_subtype(V) function returns the subtype for
5450: ** an [application-defined SQL function] argument V. The subtype
5451: ** information can be used to pass a limited amount of context from
5452: ** one SQL function to another. Use the [sqlite3_result_subtype()]
5453: ** routine to set the subtype for the return value of an SQL function.
5454: */
5455: SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*);
5456:
5457: /*
5458: ** CAPI3REF: Copy And Free SQL Values
5459: ** METHOD: sqlite3_value
5460: **
5461: ** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
5462: ** object D and returns a pointer to that copy. ^The [sqlite3_value] returned
5463: ** is a [protected sqlite3_value] object even if the input is not.
5464: ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
5465: ** memory allocation fails.
5466: **
5467: ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
5468: ** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer
5469: ** then sqlite3_value_free(V) is a harmless no-op.
5470: */
5471: SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*);
5472: SQLITE_API void sqlite3_value_free(sqlite3_value*);
5473:
5474: /*
1.2 misho 5475: ** CAPI3REF: Obtain Aggregate Function Context
1.4 misho 5476: ** METHOD: sqlite3_context
1.2 misho 5477: **
5478: ** Implementations of aggregate SQL functions use this
5479: ** routine to allocate memory for storing their state.
5480: **
1.4.2.3 ! misho 5481: ** ^The first time the sqlite3_aggregate_context(C,N) routine is called
! 5482: ** for a particular aggregate function, SQLite allocates
! 5483: ** N bytes of memory, zeroes out that memory, and returns a pointer
1.2 misho 5484: ** to the new memory. ^On second and subsequent calls to
5485: ** sqlite3_aggregate_context() for the same aggregate function instance,
5486: ** the same buffer is returned. Sqlite3_aggregate_context() is normally
5487: ** called once for each invocation of the xStep callback and then one
5488: ** last time when the xFinal callback is invoked. ^(When no rows match
5489: ** an aggregate query, the xStep() callback of the aggregate function
5490: ** implementation is never called and xFinal() is called exactly once.
5491: ** In those cases, sqlite3_aggregate_context() might be called for the
5492: ** first time from within xFinal().)^
5493: **
1.4.2.3 ! misho 5494: ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
1.4 misho 5495: ** when first called if N is less than or equal to zero or if a memory
5496: ** allocate error occurs.
1.2 misho 5497: **
5498: ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
5499: ** determined by the N parameter on first successful call. Changing the
1.4.2.3 ! misho 5500: ** value of N in any subsequent call to sqlite3_aggregate_context() within
1.2 misho 5501: ** the same aggregate function instance will not resize the memory
1.4 misho 5502: ** allocation.)^ Within the xFinal callback, it is customary to set
1.4.2.3 ! misho 5503: ** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
1.4 misho 5504: ** pointless memory allocations occur.
1.2 misho 5505: **
1.4.2.3 ! misho 5506: ** ^SQLite automatically frees the memory allocated by
1.2 misho 5507: ** sqlite3_aggregate_context() when the aggregate query concludes.
5508: **
5509: ** The first parameter must be a copy of the
5510: ** [sqlite3_context | SQL function context] that is the first parameter
5511: ** to the xStep or xFinal callback routine that implements the aggregate
5512: ** function.
5513: **
5514: ** This routine must be called from the same thread in which
5515: ** the aggregate SQL function is running.
5516: */
5517: SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
5518:
5519: /*
5520: ** CAPI3REF: User Data For Functions
1.4 misho 5521: ** METHOD: sqlite3_context
1.2 misho 5522: **
5523: ** ^The sqlite3_user_data() interface returns a copy of
5524: ** the pointer that was the pUserData parameter (the 5th parameter)
5525: ** of the [sqlite3_create_function()]
5526: ** and [sqlite3_create_function16()] routines that originally
5527: ** registered the application defined function.
5528: **
5529: ** This routine must be called from the same thread in which
5530: ** the application-defined function is running.
5531: */
5532: SQLITE_API void *sqlite3_user_data(sqlite3_context*);
5533:
5534: /*
5535: ** CAPI3REF: Database Connection For Functions
1.4 misho 5536: ** METHOD: sqlite3_context
1.2 misho 5537: **
5538: ** ^The sqlite3_context_db_handle() interface returns a copy of
5539: ** the pointer to the [database connection] (the 1st parameter)
5540: ** of the [sqlite3_create_function()]
5541: ** and [sqlite3_create_function16()] routines that originally
5542: ** registered the application defined function.
5543: */
5544: SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
5545:
5546: /*
5547: ** CAPI3REF: Function Auxiliary Data
1.4 misho 5548: ** METHOD: sqlite3_context
1.2 misho 5549: **
1.4 misho 5550: ** These functions may be used by (non-aggregate) SQL functions to
1.2 misho 5551: ** associate metadata with argument values. If the same value is passed to
5552: ** multiple invocations of the same SQL function during query execution, under
1.4 misho 5553: ** some circumstances the associated metadata may be preserved. An example
5554: ** of where this might be useful is in a regular-expression matching
5555: ** function. The compiled version of the regular expression can be stored as
1.4.2.3 ! misho 5556: ** metadata associated with the pattern string.
1.4 misho 5557: ** Then as long as the pattern string remains the same,
5558: ** the compiled regular expression can be reused on multiple
5559: ** invocations of the same function.
1.2 misho 5560: **
1.4.2.1 misho 5561: ** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata
5562: ** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument
5563: ** value to the application-defined function. ^N is zero for the left-most
5564: ** function argument. ^If there is no metadata
5565: ** associated with the function argument, the sqlite3_get_auxdata(C,N) interface
1.4 misho 5566: ** returns a NULL pointer.
5567: **
5568: ** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
5569: ** argument of the application-defined function. ^Subsequent
5570: ** calls to sqlite3_get_auxdata(C,N) return P from the most recent
5571: ** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
5572: ** NULL if the metadata has been discarded.
5573: ** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
5574: ** SQLite will invoke the destructor function X with parameter P exactly
5575: ** once, when the metadata is discarded.
5576: ** SQLite is free to discard the metadata at any time, including: <ul>
5577: ** <li> ^(when the corresponding function parameter changes)^, or
5578: ** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
5579: ** SQL statement)^, or
5580: ** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
5581: ** parameter)^, or
1.4.2.3 ! misho 5582: ** <li> ^(during the original sqlite3_set_auxdata() call when a memory
1.4 misho 5583: ** allocation error occurs.)^ </ul>
5584: **
1.4.2.3 ! misho 5585: ** Note the last bullet in particular. The destructor X in
1.4 misho 5586: ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
5587: ** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata()
5588: ** should be called near the end of the function implementation and the
5589: ** function implementation should not make any use of P after
5590: ** sqlite3_set_auxdata() has been called.
1.2 misho 5591: **
5592: ** ^(In practice, metadata is preserved between function calls for
1.4 misho 5593: ** function parameters that are compile-time constants, including literal
5594: ** values and [parameters] and expressions composed from the same.)^
1.2 misho 5595: **
1.4.2.1 misho 5596: ** The value of the N parameter to these interfaces should be non-negative.
5597: ** Future enhancements may make use of negative N values to define new
5598: ** kinds of function caching behavior.
5599: **
1.2 misho 5600: ** These routines must be called from the same thread in which
5601: ** the SQL function is running.
5602: */
5603: SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
5604: SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
5605:
5606:
5607: /*
5608: ** CAPI3REF: Constants Defining Special Destructor Behavior
5609: **
5610: ** These are special values for the destructor that is passed in as the
5611: ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
5612: ** argument is SQLITE_STATIC, it means that the content pointer is constant
5613: ** and will never change. It does not need to be destroyed. ^The
5614: ** SQLITE_TRANSIENT value means that the content will likely change in
5615: ** the near future and that SQLite should make its own private copy of
5616: ** the content before returning.
5617: **
5618: ** The typedef is necessary to work around problems in certain
1.4 misho 5619: ** C++ compilers.
1.2 misho 5620: */
5621: typedef void (*sqlite3_destructor_type)(void*);
5622: #define SQLITE_STATIC ((sqlite3_destructor_type)0)
5623: #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
5624:
5625: /*
5626: ** CAPI3REF: Setting The Result Of An SQL Function
1.4 misho 5627: ** METHOD: sqlite3_context
1.2 misho 5628: **
5629: ** These routines are used by the xFunc or xFinal callbacks that
5630: ** implement SQL functions and aggregates. See
5631: ** [sqlite3_create_function()] and [sqlite3_create_function16()]
5632: ** for additional information.
5633: **
5634: ** These functions work very much like the [parameter binding] family of
5635: ** functions used to bind values to host parameters in prepared statements.
5636: ** Refer to the [SQL parameter] documentation for additional information.
5637: **
5638: ** ^The sqlite3_result_blob() interface sets the result from
5639: ** an application-defined function to be the BLOB whose content is pointed
5640: ** to by the second parameter and which is N bytes long where N is the
5641: ** third parameter.
5642: **
1.4 misho 5643: ** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
5644: ** interfaces set the result of the application-defined function to be
5645: ** a BLOB containing all zero bytes and N bytes in size.
1.2 misho 5646: **
5647: ** ^The sqlite3_result_double() interface sets the result from
5648: ** an application-defined function to be a floating point value specified
5649: ** by its 2nd argument.
5650: **
5651: ** ^The sqlite3_result_error() and sqlite3_result_error16() functions
5652: ** cause the implemented SQL function to throw an exception.
5653: ** ^SQLite uses the string pointed to by the
5654: ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
5655: ** as the text of an error message. ^SQLite interprets the error
5656: ** message string from sqlite3_result_error() as UTF-8. ^SQLite
1.4.2.3 ! misho 5657: ** interprets the string from sqlite3_result_error16() as UTF-16 using
! 5658: ** the same [byte-order determination rules] as [sqlite3_bind_text16()].
! 5659: ** ^If the third parameter to sqlite3_result_error()
1.2 misho 5660: ** or sqlite3_result_error16() is negative then SQLite takes as the error
5661: ** message all text up through the first zero character.
5662: ** ^If the third parameter to sqlite3_result_error() or
5663: ** sqlite3_result_error16() is non-negative then SQLite takes that many
5664: ** bytes (not characters) from the 2nd parameter as the error message.
5665: ** ^The sqlite3_result_error() and sqlite3_result_error16()
5666: ** routines make a private copy of the error message text before
5667: ** they return. Hence, the calling function can deallocate or
5668: ** modify the text after they return without harm.
5669: ** ^The sqlite3_result_error_code() function changes the error code
5670: ** returned by SQLite as a result of an error in a function. ^By default,
5671: ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
5672: ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
5673: **
1.3 misho 5674: ** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
5675: ** error indicating that a string or BLOB is too long to represent.
1.2 misho 5676: **
1.3 misho 5677: ** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
5678: ** error indicating that a memory allocation failed.
1.2 misho 5679: **
5680: ** ^The sqlite3_result_int() interface sets the return value
5681: ** of the application-defined function to be the 32-bit signed integer
5682: ** value given in the 2nd argument.
5683: ** ^The sqlite3_result_int64() interface sets the return value
5684: ** of the application-defined function to be the 64-bit signed integer
5685: ** value given in the 2nd argument.
5686: **
5687: ** ^The sqlite3_result_null() interface sets the return value
5688: ** of the application-defined function to be NULL.
5689: **
5690: ** ^The sqlite3_result_text(), sqlite3_result_text16(),
5691: ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
5692: ** set the return value of the application-defined function to be
5693: ** a text string which is represented as UTF-8, UTF-16 native byte order,
5694: ** UTF-16 little endian, or UTF-16 big endian, respectively.
1.4 misho 5695: ** ^The sqlite3_result_text64() interface sets the return value of an
5696: ** application-defined function to be a text string in an encoding
5697: ** specified by the fifth (and last) parameter, which must be one
5698: ** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
1.2 misho 5699: ** ^SQLite takes the text result from the application from
5700: ** the 2nd parameter of the sqlite3_result_text* interfaces.
5701: ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
5702: ** is negative, then SQLite takes result text from the 2nd parameter
5703: ** through the first zero character.
5704: ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
5705: ** is non-negative, then as many bytes (not characters) of the text
5706: ** pointed to by the 2nd parameter are taken as the application-defined
5707: ** function result. If the 3rd parameter is non-negative, then it
5708: ** must be the byte offset into the string where the NUL terminator would
5709: ** appear if the string where NUL terminated. If any NUL characters occur
5710: ** in the string at a byte offset that is less than the value of the 3rd
5711: ** parameter, then the resulting string will contain embedded NULs and the
5712: ** result of expressions operating on strings with embedded NULs is undefined.
5713: ** ^If the 4th parameter to the sqlite3_result_text* interfaces
5714: ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
5715: ** function as the destructor on the text or BLOB result when it has
5716: ** finished using that result.
5717: ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
5718: ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
5719: ** assumes that the text or BLOB result is in constant space and does not
5720: ** copy the content of the parameter nor call a destructor on the content
5721: ** when it has finished using that result.
5722: ** ^If the 4th parameter to the sqlite3_result_text* interfaces
5723: ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
1.4.2.2 misho 5724: ** then SQLite makes a copy of the result into space obtained
1.2 misho 5725: ** from [sqlite3_malloc()] before it returns.
5726: **
1.4.2.3 ! misho 5727: ** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and
! 5728: ** sqlite3_result_text16be() routines, and for sqlite3_result_text64()
! 5729: ** when the encoding is not UTF8, if the input UTF16 begins with a
! 5730: ** byte-order mark (BOM, U+FEFF) then the BOM is removed from the
! 5731: ** string and the rest of the string is interpreted according to the
! 5732: ** byte-order specified by the BOM. ^The byte-order specified by
! 5733: ** the BOM at the beginning of the text overrides the byte-order
! 5734: ** specified by the interface procedure. ^So, for example, if
! 5735: ** sqlite3_result_text16le() is invoked with text that begins
! 5736: ** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the
! 5737: ** first two bytes of input are skipped and the remaining input
! 5738: ** is interpreted as UTF16BE text.
! 5739: **
! 5740: ** ^For UTF16 input text to the sqlite3_result_text16(),
! 5741: ** sqlite3_result_text16be(), sqlite3_result_text16le(), and
! 5742: ** sqlite3_result_text64() routines, if the text contains invalid
! 5743: ** UTF16 characters, the invalid characters might be converted
! 5744: ** into the unicode replacement character, U+FFFD.
! 5745: **
1.2 misho 5746: ** ^The sqlite3_result_value() interface sets the result of
1.4 misho 5747: ** the application-defined function to be a copy of the
1.2 misho 5748: ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
5749: ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
5750: ** so that the [sqlite3_value] specified in the parameter may change or
5751: ** be deallocated after sqlite3_result_value() returns without harm.
5752: ** ^A [protected sqlite3_value] object may always be used where an
5753: ** [unprotected sqlite3_value] object is required, so either
5754: ** kind of [sqlite3_value] object can be used with this interface.
5755: **
1.4.2.2 misho 5756: ** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an
5757: ** SQL NULL value, just like [sqlite3_result_null(C)], except that it
1.4.2.3 ! misho 5758: ** also associates the host-language pointer P or type T with that
1.4.2.2 misho 5759: ** NULL value such that the pointer can be retrieved within an
5760: ** [application-defined SQL function] using [sqlite3_value_pointer()].
5761: ** ^If the D parameter is not NULL, then it is a pointer to a destructor
5762: ** for the P parameter. ^SQLite invokes D with P as its only argument
5763: ** when SQLite is finished with P. The T parameter should be a static
5764: ** string and preferably a string literal. The sqlite3_result_pointer()
5765: ** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
5766: **
1.2 misho 5767: ** If these routines are called from within the different thread
5768: ** than the one containing the application-defined function that received
5769: ** the [sqlite3_context] pointer, the results are undefined.
5770: */
5771: SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
1.4 misho 5772: SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*,
5773: sqlite3_uint64,void(*)(void*));
1.2 misho 5774: SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
5775: SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
5776: SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
5777: SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
5778: SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
5779: SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
5780: SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
5781: SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
5782: SQLITE_API void sqlite3_result_null(sqlite3_context*);
5783: SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
1.4 misho 5784: SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64,
5785: void(*)(void*), unsigned char encoding);
1.2 misho 5786: SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
5787: SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
5788: SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
5789: SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
1.4.2.2 misho 5790: SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*));
1.2 misho 5791: SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
1.4 misho 5792: SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
5793:
5794:
5795: /*
5796: ** CAPI3REF: Setting The Subtype Of An SQL Function
5797: ** METHOD: sqlite3_context
5798: **
5799: ** The sqlite3_result_subtype(C,T) function causes the subtype of
1.4.2.3 ! misho 5800: ** the result from the [application-defined SQL function] with
! 5801: ** [sqlite3_context] C to be the value T. Only the lower 8 bits
1.4 misho 5802: ** of the subtype T are preserved in current versions of SQLite;
5803: ** higher order bits are discarded.
5804: ** The number of subtype bytes preserved by SQLite might increase
5805: ** in future releases of SQLite.
5806: */
5807: SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int);
1.2 misho 5808:
5809: /*
5810: ** CAPI3REF: Define New Collating Sequences
1.4 misho 5811: ** METHOD: sqlite3
1.2 misho 5812: **
5813: ** ^These functions add, remove, or modify a [collation] associated
5814: ** with the [database connection] specified as the first argument.
5815: **
5816: ** ^The name of the collation is a UTF-8 string
5817: ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
5818: ** and a UTF-16 string in native byte order for sqlite3_create_collation16().
5819: ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
5820: ** considered to be the same name.
5821: **
5822: ** ^(The third argument (eTextRep) must be one of the constants:
5823: ** <ul>
5824: ** <li> [SQLITE_UTF8],
5825: ** <li> [SQLITE_UTF16LE],
5826: ** <li> [SQLITE_UTF16BE],
5827: ** <li> [SQLITE_UTF16], or
5828: ** <li> [SQLITE_UTF16_ALIGNED].
5829: ** </ul>)^
5830: ** ^The eTextRep argument determines the encoding of strings passed
1.4.2.3 ! misho 5831: ** to the collating function callback, xCompare.
1.2 misho 5832: ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
5833: ** force strings to be UTF16 with native byte order.
5834: ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
5835: ** on an even byte address.
5836: **
5837: ** ^The fourth argument, pArg, is an application data pointer that is passed
5838: ** through as the first argument to the collating function callback.
5839: **
1.4.2.3 ! misho 5840: ** ^The fifth argument, xCompare, is a pointer to the collating function.
1.2 misho 5841: ** ^Multiple collating functions can be registered using the same name but
5842: ** with different eTextRep parameters and SQLite will use whichever
5843: ** function requires the least amount of data transformation.
1.4.2.3 ! misho 5844: ** ^If the xCompare argument is NULL then the collating function is
1.2 misho 5845: ** deleted. ^When all collating functions having the same name are deleted,
5846: ** that collation is no longer usable.
5847: **
1.4.2.3 ! misho 5848: ** ^The collating function callback is invoked with a copy of the pArg
1.2 misho 5849: ** application data pointer and with two strings in the encoding specified
1.4.2.3 ! misho 5850: ** by the eTextRep argument. The two integer parameters to the collating
! 5851: ** function callback are the length of the two strings, in bytes. The collating
! 5852: ** function must return an integer that is negative, zero, or positive
1.2 misho 5853: ** if the first string is less than, equal to, or greater than the second,
5854: ** respectively. A collating function must always return the same answer
5855: ** given the same inputs. If two or more collating functions are registered
5856: ** to the same collation name (using different eTextRep values) then all
5857: ** must give an equivalent answer when invoked with equivalent strings.
5858: ** The collating function must obey the following properties for all
5859: ** strings A, B, and C:
5860: **
5861: ** <ol>
5862: ** <li> If A==B then B==A.
5863: ** <li> If A==B and B==C then A==C.
5864: ** <li> If A<B THEN B>A.
5865: ** <li> If A<B and B<C then A<C.
5866: ** </ol>
5867: **
5868: ** If a collating function fails any of the above constraints and that
1.4.2.3 ! misho 5869: ** collating function is registered and used, then the behavior of SQLite
1.2 misho 5870: ** is undefined.
5871: **
5872: ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
5873: ** with the addition that the xDestroy callback is invoked on pArg when
5874: ** the collating function is deleted.
5875: ** ^Collating functions are deleted when they are overridden by later
5876: ** calls to the collation creation functions or when the
5877: ** [database connection] is closed using [sqlite3_close()].
5878: **
1.4.2.3 ! misho 5879: ** ^The xDestroy callback is <u>not</u> called if the
1.2 misho 5880: ** sqlite3_create_collation_v2() function fails. Applications that invoke
1.4.2.3 ! misho 5881: ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
1.2 misho 5882: ** check the return code and dispose of the application data pointer
5883: ** themselves rather than expecting SQLite to deal with it for them.
1.4.2.3 ! misho 5884: ** This is different from every other SQLite interface. The inconsistency
! 5885: ** is unfortunate but cannot be changed without breaking backwards
1.2 misho 5886: ** compatibility.
5887: **
5888: ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
5889: */
5890: SQLITE_API int sqlite3_create_collation(
1.4.2.3 ! misho 5891: sqlite3*,
! 5892: const char *zName,
! 5893: int eTextRep,
1.2 misho 5894: void *pArg,
5895: int(*xCompare)(void*,int,const void*,int,const void*)
5896: );
5897: SQLITE_API int sqlite3_create_collation_v2(
1.4.2.3 ! misho 5898: sqlite3*,
! 5899: const char *zName,
! 5900: int eTextRep,
1.2 misho 5901: void *pArg,
5902: int(*xCompare)(void*,int,const void*,int,const void*),
5903: void(*xDestroy)(void*)
5904: );
5905: SQLITE_API int sqlite3_create_collation16(
1.4.2.3 ! misho 5906: sqlite3*,
1.2 misho 5907: const void *zName,
1.4.2.3 ! misho 5908: int eTextRep,
1.2 misho 5909: void *pArg,
5910: int(*xCompare)(void*,int,const void*,int,const void*)
5911: );
5912:
5913: /*
5914: ** CAPI3REF: Collation Needed Callbacks
1.4 misho 5915: ** METHOD: sqlite3
1.2 misho 5916: **
5917: ** ^To avoid having to register all collation sequences before a database
5918: ** can be used, a single callback function may be registered with the
5919: ** [database connection] to be invoked whenever an undefined collation
5920: ** sequence is required.
5921: **
5922: ** ^If the function is registered using the sqlite3_collation_needed() API,
5923: ** then it is passed the names of undefined collation sequences as strings
5924: ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
5925: ** the names are passed as UTF-16 in machine native byte order.
5926: ** ^A call to either function replaces the existing collation-needed callback.
5927: **
5928: ** ^(When the callback is invoked, the first argument passed is a copy
5929: ** of the second argument to sqlite3_collation_needed() or
5930: ** sqlite3_collation_needed16(). The second argument is the database
5931: ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
5932: ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
5933: ** sequence function required. The fourth parameter is the name of the
5934: ** required collation sequence.)^
5935: **
5936: ** The callback function should register the desired collation using
5937: ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
5938: ** [sqlite3_create_collation_v2()].
5939: */
5940: SQLITE_API int sqlite3_collation_needed(
1.4.2.3 ! misho 5941: sqlite3*,
! 5942: void*,
1.2 misho 5943: void(*)(void*,sqlite3*,int eTextRep,const char*)
5944: );
5945: SQLITE_API int sqlite3_collation_needed16(
1.4.2.3 ! misho 5946: sqlite3*,
1.2 misho 5947: void*,
5948: void(*)(void*,sqlite3*,int eTextRep,const void*)
5949: );
5950:
5951: #ifdef SQLITE_ENABLE_CEROD
5952: /*
1.4.2.3 ! misho 5953: ** Specify the activation key for a CEROD database. Unless
1.2 misho 5954: ** activated, none of the CEROD routines will work.
5955: */
5956: SQLITE_API void sqlite3_activate_cerod(
5957: const char *zPassPhrase /* Activation phrase */
5958: );
5959: #endif
5960:
5961: /*
5962: ** CAPI3REF: Suspend Execution For A Short Time
5963: **
5964: ** The sqlite3_sleep() function causes the current thread to suspend execution
5965: ** for at least a number of milliseconds specified in its parameter.
5966: **
5967: ** If the operating system does not support sleep requests with
5968: ** millisecond time resolution, then the time will be rounded up to
5969: ** the nearest second. The number of milliseconds of sleep actually
5970: ** requested from the operating system is returned.
5971: **
5972: ** ^SQLite implements this interface by calling the xSleep()
5973: ** method of the default [sqlite3_vfs] object. If the xSleep() method
5974: ** of the default VFS is not implemented correctly, or not implemented at
5975: ** all, then the behavior of sqlite3_sleep() may deviate from the description
5976: ** in the previous paragraphs.
5977: */
5978: SQLITE_API int sqlite3_sleep(int);
5979:
5980: /*
5981: ** CAPI3REF: Name Of The Folder Holding Temporary Files
5982: **
5983: ** ^(If this global variable is made to point to a string which is
5984: ** the name of a folder (a.k.a. directory), then all temporary files
5985: ** created by SQLite when using a built-in [sqlite3_vfs | VFS]
5986: ** will be placed in that directory.)^ ^If this variable
5987: ** is a NULL pointer, then SQLite performs a search for an appropriate
5988: ** temporary file directory.
5989: **
1.4 misho 5990: ** Applications are strongly discouraged from using this global variable.
5991: ** It is required to set a temporary folder on Windows Runtime (WinRT).
5992: ** But for all other platforms, it is highly recommended that applications
5993: ** neither read nor write this variable. This global variable is a relic
5994: ** that exists for backwards compatibility of legacy applications and should
5995: ** be avoided in new projects.
5996: **
1.2 misho 5997: ** It is not safe to read or modify this variable in more than one
5998: ** thread at a time. It is not safe to read or modify this variable
5999: ** if a [database connection] is being used at the same time in a separate
6000: ** thread.
6001: ** It is intended that this variable be set once
6002: ** as part of process initialization and before any SQLite interface
6003: ** routines have been called and that this variable remain unchanged
6004: ** thereafter.
6005: **
6006: ** ^The [temp_store_directory pragma] may modify this variable and cause
6007: ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
6008: ** the [temp_store_directory pragma] always assumes that any string
1.4.2.3 ! misho 6009: ** that this variable points to is held in memory obtained from
1.2 misho 6010: ** [sqlite3_malloc] and the pragma may attempt to free that memory
6011: ** using [sqlite3_free].
6012: ** Hence, if this variable is modified directly, either it should be
6013: ** made NULL or made to point to memory obtained from [sqlite3_malloc]
6014: ** or else the use of the [temp_store_directory pragma] should be avoided.
1.4 misho 6015: ** Except when requested by the [temp_store_directory pragma], SQLite
6016: ** does not free the memory that sqlite3_temp_directory points to. If
6017: ** the application wants that memory to be freed, it must do
6018: ** so itself, taking care to only do so after all [database connection]
6019: ** objects have been destroyed.
1.3 misho 6020: **
6021: ** <b>Note to Windows Runtime users:</b> The temporary directory must be set
6022: ** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various
6023: ** features that require the use of temporary files may fail. Here is an
6024: ** example of how to do this using C++ with the Windows Runtime:
6025: **
6026: ** <blockquote><pre>
6027: ** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
6028: ** TemporaryFolder->Path->Data();
6029: ** char zPathBuf[MAX_PATH + 1];
6030: ** memset(zPathBuf, 0, sizeof(zPathBuf));
6031: ** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
6032: ** NULL, NULL);
6033: ** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
6034: ** </pre></blockquote>
1.2 misho 6035: */
6036: SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
6037:
6038: /*
1.3 misho 6039: ** CAPI3REF: Name Of The Folder Holding Database Files
6040: **
6041: ** ^(If this global variable is made to point to a string which is
6042: ** the name of a folder (a.k.a. directory), then all database files
6043: ** specified with a relative pathname and created or accessed by
6044: ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
6045: ** to be relative to that directory.)^ ^If this variable is a NULL
6046: ** pointer, then SQLite assumes that all database files specified
6047: ** with a relative pathname are relative to the current directory
6048: ** for the process. Only the windows VFS makes use of this global
6049: ** variable; it is ignored by the unix VFS.
6050: **
6051: ** Changing the value of this variable while a database connection is
6052: ** open can result in a corrupt database.
6053: **
6054: ** It is not safe to read or modify this variable in more than one
6055: ** thread at a time. It is not safe to read or modify this variable
6056: ** if a [database connection] is being used at the same time in a separate
6057: ** thread.
6058: ** It is intended that this variable be set once
6059: ** as part of process initialization and before any SQLite interface
6060: ** routines have been called and that this variable remain unchanged
6061: ** thereafter.
6062: **
6063: ** ^The [data_store_directory pragma] may modify this variable and cause
6064: ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
6065: ** the [data_store_directory pragma] always assumes that any string
1.4.2.3 ! misho 6066: ** that this variable points to is held in memory obtained from
1.3 misho 6067: ** [sqlite3_malloc] and the pragma may attempt to free that memory
6068: ** using [sqlite3_free].
6069: ** Hence, if this variable is modified directly, either it should be
6070: ** made NULL or made to point to memory obtained from [sqlite3_malloc]
6071: ** or else the use of the [data_store_directory pragma] should be avoided.
6072: */
6073: SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory;
6074:
6075: /*
1.4.2.2 misho 6076: ** CAPI3REF: Win32 Specific Interface
6077: **
6078: ** These interfaces are available only on Windows. The
6079: ** [sqlite3_win32_set_directory] interface is used to set the value associated
6080: ** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to
6081: ** zValue, depending on the value of the type parameter. The zValue parameter
6082: ** should be NULL to cause the previous value to be freed via [sqlite3_free];
6083: ** a non-NULL value will be copied into memory obtained from [sqlite3_malloc]
6084: ** prior to being used. The [sqlite3_win32_set_directory] interface returns
6085: ** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported,
6086: ** or [SQLITE_NOMEM] if memory could not be allocated. The value of the
6087: ** [sqlite3_data_directory] variable is intended to act as a replacement for
6088: ** the current directory on the sub-platforms of Win32 where that concept is
6089: ** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and
6090: ** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the
6091: ** sqlite3_win32_set_directory interface except the string parameter must be
6092: ** UTF-8 or UTF-16, respectively.
6093: */
6094: SQLITE_API int sqlite3_win32_set_directory(
6095: unsigned long type, /* Identifier for directory being set or reset */
6096: void *zValue /* New value for directory being set or reset */
6097: );
6098: SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue);
6099: SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue);
6100:
6101: /*
6102: ** CAPI3REF: Win32 Directory Types
6103: **
6104: ** These macros are only available on Windows. They define the allowed values
6105: ** for the type argument to the [sqlite3_win32_set_directory] interface.
6106: */
6107: #define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1
6108: #define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2
6109:
6110: /*
1.2 misho 6111: ** CAPI3REF: Test For Auto-Commit Mode
6112: ** KEYWORDS: {autocommit mode}
1.4 misho 6113: ** METHOD: sqlite3
1.2 misho 6114: **
6115: ** ^The sqlite3_get_autocommit() interface returns non-zero or
6116: ** zero if the given database connection is or is not in autocommit mode,
6117: ** respectively. ^Autocommit mode is on by default.
6118: ** ^Autocommit mode is disabled by a [BEGIN] statement.
6119: ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
6120: **
6121: ** If certain kinds of errors occur on a statement within a multi-statement
6122: ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
6123: ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
6124: ** transaction might be rolled back automatically. The only way to
6125: ** find out whether SQLite automatically rolled back the transaction after
6126: ** an error is to use this function.
6127: **
6128: ** If another thread changes the autocommit status of the database
6129: ** connection while this routine is running, then the return value
6130: ** is undefined.
6131: */
6132: SQLITE_API int sqlite3_get_autocommit(sqlite3*);
6133:
6134: /*
6135: ** CAPI3REF: Find The Database Handle Of A Prepared Statement
1.4 misho 6136: ** METHOD: sqlite3_stmt
1.2 misho 6137: **
6138: ** ^The sqlite3_db_handle interface returns the [database connection] handle
6139: ** to which a [prepared statement] belongs. ^The [database connection]
6140: ** returned by sqlite3_db_handle is the same [database connection]
6141: ** that was the first argument
6142: ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
6143: ** create the statement in the first place.
6144: */
6145: SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
6146:
6147: /*
6148: ** CAPI3REF: Return The Filename For A Database Connection
1.4 misho 6149: ** METHOD: sqlite3
1.2 misho 6150: **
1.4.2.3 ! misho 6151: ** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename
! 6152: ** associated with database N of connection D.
! 6153: ** ^If there is no attached database N on the database
1.2 misho 6154: ** connection D, or if database N is a temporary or in-memory database, then
1.4.2.2 misho 6155: ** this function will return either a NULL pointer or an empty string.
1.2 misho 6156: **
1.4.2.3 ! misho 6157: ** ^The string value returned by this routine is owned and managed by
! 6158: ** the database connection. ^The value will be valid until the database N
! 6159: ** is [DETACH]-ed or until the database connection closes.
! 6160: **
1.2 misho 6161: ** ^The filename returned by this function is the output of the
6162: ** xFullPathname method of the [VFS]. ^In other words, the filename
6163: ** will be an absolute pathname, even if the filename used
6164: ** to open the database originally was a URI or relative pathname.
1.4.2.3 ! misho 6165: **
! 6166: ** If the filename pointer returned by this routine is not NULL, then it
! 6167: ** can be used as the filename input parameter to these routines:
! 6168: ** <ul>
! 6169: ** <li> [sqlite3_uri_parameter()]
! 6170: ** <li> [sqlite3_uri_boolean()]
! 6171: ** <li> [sqlite3_uri_int64()]
! 6172: ** <li> [sqlite3_filename_database()]
! 6173: ** <li> [sqlite3_filename_journal()]
! 6174: ** <li> [sqlite3_filename_wal()]
! 6175: ** </ul>
1.2 misho 6176: */
6177: SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);
6178:
6179: /*
1.3 misho 6180: ** CAPI3REF: Determine if a database is read-only
1.4 misho 6181: ** METHOD: sqlite3
1.3 misho 6182: **
6183: ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
6184: ** of connection D is read-only, 0 if it is read/write, or -1 if N is not
6185: ** the name of a database on connection D.
6186: */
6187: SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
6188:
6189: /*
1.2 misho 6190: ** CAPI3REF: Find the next prepared statement
1.4 misho 6191: ** METHOD: sqlite3
1.2 misho 6192: **
6193: ** ^This interface returns a pointer to the next [prepared statement] after
6194: ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
6195: ** then this interface returns a pointer to the first prepared statement
6196: ** associated with the database connection pDb. ^If no prepared statement
6197: ** satisfies the conditions of this routine, it returns NULL.
6198: **
6199: ** The [database connection] pointer D in a call to
6200: ** [sqlite3_next_stmt(D,S)] must refer to an open database
6201: ** connection and in particular must not be a NULL pointer.
6202: */
6203: SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
6204:
6205: /*
6206: ** CAPI3REF: Commit And Rollback Notification Callbacks
1.4 misho 6207: ** METHOD: sqlite3
1.2 misho 6208: **
6209: ** ^The sqlite3_commit_hook() interface registers a callback
6210: ** function to be invoked whenever a transaction is [COMMIT | committed].
6211: ** ^Any callback set by a previous call to sqlite3_commit_hook()
6212: ** for the same database connection is overridden.
6213: ** ^The sqlite3_rollback_hook() interface registers a callback
6214: ** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
6215: ** ^Any callback set by a previous call to sqlite3_rollback_hook()
6216: ** for the same database connection is overridden.
6217: ** ^The pArg argument is passed through to the callback.
6218: ** ^If the callback on a commit hook function returns non-zero,
6219: ** then the commit is converted into a rollback.
6220: **
6221: ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
6222: ** return the P argument from the previous call of the same function
6223: ** on the same [database connection] D, or NULL for
6224: ** the first call for each function on D.
6225: **
6226: ** The commit and rollback hook callbacks are not reentrant.
6227: ** The callback implementation must not do anything that will modify
6228: ** the database connection that invoked the callback. Any actions
6229: ** to modify the database connection must be deferred until after the
6230: ** completion of the [sqlite3_step()] call that triggered the commit
6231: ** or rollback hook in the first place.
6232: ** Note that running any other SQL statements, including SELECT statements,
6233: ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
6234: ** the database connections for the meaning of "modify" in this paragraph.
6235: **
6236: ** ^Registering a NULL function disables the callback.
6237: **
6238: ** ^When the commit hook callback routine returns zero, the [COMMIT]
6239: ** operation is allowed to continue normally. ^If the commit hook
6240: ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
6241: ** ^The rollback hook is invoked on a rollback that results from a commit
6242: ** hook returning non-zero, just as it would be with any other rollback.
6243: **
6244: ** ^For the purposes of this API, a transaction is said to have been
6245: ** rolled back if an explicit "ROLLBACK" statement is executed, or
6246: ** an error or constraint causes an implicit rollback to occur.
6247: ** ^The rollback callback is not invoked if a transaction is
6248: ** automatically rolled back because the database connection is closed.
6249: **
6250: ** See also the [sqlite3_update_hook()] interface.
6251: */
6252: SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
6253: SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
6254:
6255: /*
6256: ** CAPI3REF: Data Change Notification Callbacks
1.4 misho 6257: ** METHOD: sqlite3
1.2 misho 6258: **
6259: ** ^The sqlite3_update_hook() interface registers a callback function
6260: ** with the [database connection] identified by the first argument
1.4 misho 6261: ** to be invoked whenever a row is updated, inserted or deleted in
6262: ** a [rowid table].
1.2 misho 6263: ** ^Any callback set by a previous call to this function
6264: ** for the same database connection is overridden.
6265: **
6266: ** ^The second argument is a pointer to the function to invoke when a
1.4 misho 6267: ** row is updated, inserted or deleted in a rowid table.
1.2 misho 6268: ** ^The first argument to the callback is a copy of the third argument
6269: ** to sqlite3_update_hook().
6270: ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
6271: ** or [SQLITE_UPDATE], depending on the operation that caused the callback
6272: ** to be invoked.
6273: ** ^The third and fourth arguments to the callback contain pointers to the
6274: ** database and table name containing the affected row.
6275: ** ^The final callback parameter is the [rowid] of the row.
6276: ** ^In the case of an update, this is the [rowid] after the update takes place.
6277: **
6278: ** ^(The update hook is not invoked when internal system tables are
1.4.2.3 ! misho 6279: ** modified (i.e. sqlite_sequence).)^
1.4 misho 6280: ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
1.2 misho 6281: **
6282: ** ^In the current implementation, the update hook
1.4.2.1 misho 6283: ** is not invoked when conflicting rows are deleted because of an
1.2 misho 6284: ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
6285: ** invoked when rows are deleted using the [truncate optimization].
6286: ** The exceptions defined in this paragraph might change in a future
6287: ** release of SQLite.
6288: **
6289: ** The update hook implementation must not do anything that will modify
6290: ** the database connection that invoked the update hook. Any actions
6291: ** to modify the database connection must be deferred until after the
6292: ** completion of the [sqlite3_step()] call that triggered the update hook.
6293: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
6294: ** database connections for the meaning of "modify" in this paragraph.
6295: **
6296: ** ^The sqlite3_update_hook(D,C,P) function
6297: ** returns the P argument from the previous call
6298: ** on the same [database connection] D, or NULL for
6299: ** the first call on D.
6300: **
1.4 misho 6301: ** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()],
6302: ** and [sqlite3_preupdate_hook()] interfaces.
1.2 misho 6303: */
6304: SQLITE_API void *sqlite3_update_hook(
1.4.2.3 ! misho 6305: sqlite3*,
1.2 misho 6306: void(*)(void *,int ,char const *,char const *,sqlite3_int64),
6307: void*
6308: );
6309:
6310: /*
6311: ** CAPI3REF: Enable Or Disable Shared Pager Cache
6312: **
6313: ** ^(This routine enables or disables the sharing of the database cache
6314: ** and schema data structures between [database connection | connections]
6315: ** to the same database. Sharing is enabled if the argument is true
6316: ** and disabled if the argument is false.)^
6317: **
6318: ** ^Cache sharing is enabled and disabled for an entire process.
1.4.2.3 ! misho 6319: ** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]).
1.4.2.1 misho 6320: ** In prior versions of SQLite,
1.2 misho 6321: ** sharing was enabled or disabled for each thread separately.
6322: **
6323: ** ^(The cache sharing mode set by this interface effects all subsequent
6324: ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
1.4.2.3 ! misho 6325: ** Existing database connections continue to use the sharing mode
1.2 misho 6326: ** that was in effect at the time they were opened.)^
6327: **
6328: ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
6329: ** successfully. An [error code] is returned otherwise.)^
6330: **
1.4.2.3 ! misho 6331: ** ^Shared cache is disabled by default. It is recommended that it stay
! 6332: ** that way. In other words, do not use this routine. This interface
! 6333: ** continues to be provided for historical compatibility, but its use is
! 6334: ** discouraged. Any use of shared cache is discouraged. If shared cache
! 6335: ** must be used, it is recommended that shared cache only be enabled for
! 6336: ** individual database connections using the [sqlite3_open_v2()] interface
! 6337: ** with the [SQLITE_OPEN_SHAREDCACHE] flag.
1.2 misho 6338: **
1.4 misho 6339: ** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
1.4.2.3 ! misho 6340: ** and will always return SQLITE_MISUSE. On those systems,
! 6341: ** shared cache mode should be enabled per-database connection via
1.4 misho 6342: ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
6343: **
1.3 misho 6344: ** This interface is threadsafe on processors where writing a
6345: ** 32-bit integer is atomic.
6346: **
1.2 misho 6347: ** See Also: [SQLite Shared-Cache Mode]
6348: */
6349: SQLITE_API int sqlite3_enable_shared_cache(int);
6350:
6351: /*
6352: ** CAPI3REF: Attempt To Free Heap Memory
6353: **
6354: ** ^The sqlite3_release_memory() interface attempts to free N bytes
6355: ** of heap memory by deallocating non-essential memory allocations
6356: ** held by the database library. Memory used to cache database
6357: ** pages to improve performance is an example of non-essential memory.
6358: ** ^sqlite3_release_memory() returns the number of bytes actually freed,
6359: ** which might be more or less than the amount requested.
6360: ** ^The sqlite3_release_memory() routine is a no-op returning zero
6361: ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
6362: **
6363: ** See also: [sqlite3_db_release_memory()]
6364: */
6365: SQLITE_API int sqlite3_release_memory(int);
6366:
6367: /*
6368: ** CAPI3REF: Free Memory Used By A Database Connection
1.4 misho 6369: ** METHOD: sqlite3
1.2 misho 6370: **
6371: ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
6372: ** memory as possible from database connection D. Unlike the
1.4 misho 6373: ** [sqlite3_release_memory()] interface, this interface is in effect even
6374: ** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
1.2 misho 6375: ** omitted.
6376: **
6377: ** See also: [sqlite3_release_memory()]
6378: */
6379: SQLITE_API int sqlite3_db_release_memory(sqlite3*);
6380:
6381: /*
6382: ** CAPI3REF: Impose A Limit On Heap Size
6383: **
1.4.2.3 ! misho 6384: ** These interfaces impose limits on the amount of heap memory that will be
! 6385: ** by all database connections within a single process.
! 6386: **
1.2 misho 6387: ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
6388: ** soft limit on the amount of heap memory that may be allocated by SQLite.
6389: ** ^SQLite strives to keep heap memory utilization below the soft heap
6390: ** limit by reducing the number of pages held in the page cache
6391: ** as heap memory usages approaches the limit.
6392: ** ^The soft heap limit is "soft" because even though SQLite strives to stay
6393: ** below the limit, it will exceed the limit rather than generate
1.4.2.3 ! misho 6394: ** an [SQLITE_NOMEM] error. In other words, the soft heap limit
1.2 misho 6395: ** is advisory only.
6396: **
1.4.2.3 ! misho 6397: ** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of
! 6398: ** N bytes on the amount of memory that will be allocated. ^The
! 6399: ** sqlite3_hard_heap_limit64(N) interface is similar to
! 6400: ** sqlite3_soft_heap_limit64(N) except that memory allocations will fail
! 6401: ** when the hard heap limit is reached.
! 6402: **
! 6403: ** ^The return value from both sqlite3_soft_heap_limit64() and
! 6404: ** sqlite3_hard_heap_limit64() is the size of
! 6405: ** the heap limit prior to the call, or negative in the case of an
1.2 misho 6406: ** error. ^If the argument N is negative
1.4.2.3 ! misho 6407: ** then no change is made to the heap limit. Hence, the current
! 6408: ** size of heap limits can be determined by invoking
! 6409: ** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1).
! 6410: **
! 6411: ** ^Setting the heap limits to zero disables the heap limiter mechanism.
! 6412: **
! 6413: ** ^The soft heap limit may not be greater than the hard heap limit.
! 6414: ** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N)
! 6415: ** is invoked with a value of N that is greater than the hard heap limit,
! 6416: ** the the soft heap limit is set to the value of the hard heap limit.
! 6417: ** ^The soft heap limit is automatically enabled whenever the hard heap
! 6418: ** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and
! 6419: ** the soft heap limit is outside the range of 1..N, then the soft heap
! 6420: ** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the
! 6421: ** hard heap limit is enabled makes the soft heap limit equal to the
! 6422: ** hard heap limit.
1.2 misho 6423: **
1.4.2.3 ! misho 6424: ** The memory allocation limits can also be adjusted using
! 6425: ** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit].
1.2 misho 6426: **
1.4.2.3 ! misho 6427: ** ^(The heap limits are not enforced in the current implementation
1.2 misho 6428: ** if one or more of following conditions are true:
6429: **
6430: ** <ul>
1.4.2.3 ! misho 6431: ** <li> The limit value is set to zero.
1.2 misho 6432: ** <li> Memory accounting is disabled using a combination of the
6433: ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
6434: ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
6435: ** <li> An alternative page cache implementation is specified using
6436: ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
6437: ** <li> The page cache allocates from its own memory pool supplied
6438: ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
6439: ** from the heap.
6440: ** </ul>)^
6441: **
1.4.2.3 ! misho 6442: ** The circumstances under which SQLite will enforce the heap limits may
1.2 misho 6443: ** changes in future releases of SQLite.
6444: */
6445: SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
1.4.2.3 ! misho 6446: SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N);
1.2 misho 6447:
6448: /*
6449: ** CAPI3REF: Deprecated Soft Heap Limit Interface
6450: ** DEPRECATED
6451: **
6452: ** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
6453: ** interface. This routine is provided for historical compatibility
6454: ** only. All new applications should use the
6455: ** [sqlite3_soft_heap_limit64()] interface rather than this one.
6456: */
6457: SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
6458:
6459:
6460: /*
6461: ** CAPI3REF: Extract Metadata About A Column Of A Table
1.4 misho 6462: ** METHOD: sqlite3
1.2 misho 6463: **
1.4 misho 6464: ** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
6465: ** information about column C of table T in database D
6466: ** on [database connection] X.)^ ^The sqlite3_table_column_metadata()
6467: ** interface returns SQLITE_OK and fills in the non-NULL pointers in
6468: ** the final five arguments with appropriate values if the specified
6469: ** column exists. ^The sqlite3_table_column_metadata() interface returns
1.4.2.3 ! misho 6470: ** SQLITE_ERROR if the specified column does not exist.
1.4 misho 6471: ** ^If the column-name parameter to sqlite3_table_column_metadata() is a
6472: ** NULL pointer, then this routine simply checks for the existence of the
6473: ** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
1.4.2.2 misho 6474: ** does not. If the table name parameter T in a call to
6475: ** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is
6476: ** undefined behavior.
1.2 misho 6477: **
6478: ** ^The column is identified by the second, third and fourth parameters to
1.4 misho 6479: ** this function. ^(The second parameter is either the name of the database
1.2 misho 6480: ** (i.e. "main", "temp", or an attached database) containing the specified
1.4 misho 6481: ** table or NULL.)^ ^If it is NULL, then all attached databases are searched
1.2 misho 6482: ** for the table using the same algorithm used by the database engine to
6483: ** resolve unqualified table references.
6484: **
6485: ** ^The third and fourth parameters to this function are the table and column
1.4 misho 6486: ** name of the desired column, respectively.
1.2 misho 6487: **
6488: ** ^Metadata is returned by writing to the memory locations passed as the 5th
6489: ** and subsequent parameters to this function. ^Any of these arguments may be
6490: ** NULL, in which case the corresponding element of metadata is omitted.
6491: **
6492: ** ^(<blockquote>
6493: ** <table border="1">
6494: ** <tr><th> Parameter <th> Output<br>Type <th> Description
6495: **
6496: ** <tr><td> 5th <td> const char* <td> Data type
6497: ** <tr><td> 6th <td> const char* <td> Name of default collation sequence
6498: ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
6499: ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
6500: ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
6501: ** </table>
6502: ** </blockquote>)^
6503: **
6504: ** ^The memory pointed to by the character pointers returned for the
1.4 misho 6505: ** declaration type and collation sequence is valid until the next
1.2 misho 6506: ** call to any SQLite API function.
6507: **
6508: ** ^If the specified table is actually a view, an [error code] is returned.
6509: **
1.4.2.3 ! misho 6510: ** ^If the specified column is "rowid", "oid" or "_rowid_" and the table
1.4 misho 6511: ** is not a [WITHOUT ROWID] table and an
1.2 misho 6512: ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
6513: ** parameters are set for the explicitly declared column. ^(If there is no
1.4 misho 6514: ** [INTEGER PRIMARY KEY] column, then the outputs
6515: ** for the [rowid] are set as follows:
1.2 misho 6516: **
6517: ** <pre>
6518: ** data type: "INTEGER"
6519: ** collation sequence: "BINARY"
6520: ** not null: 0
6521: ** primary key: 1
6522: ** auto increment: 0
6523: ** </pre>)^
6524: **
1.4 misho 6525: ** ^This function causes all database schemas to be read from disk and
6526: ** parsed, if that has not already been done, and returns an error if
6527: ** any errors are encountered while loading the schema.
1.2 misho 6528: */
6529: SQLITE_API int sqlite3_table_column_metadata(
6530: sqlite3 *db, /* Connection handle */
6531: const char *zDbName, /* Database name or NULL */
6532: const char *zTableName, /* Table name */
6533: const char *zColumnName, /* Column name */
6534: char const **pzDataType, /* OUTPUT: Declared data type */
6535: char const **pzCollSeq, /* OUTPUT: Collation sequence name */
6536: int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
6537: int *pPrimaryKey, /* OUTPUT: True if column part of PK */
6538: int *pAutoinc /* OUTPUT: True if column is auto-increment */
6539: );
6540:
6541: /*
6542: ** CAPI3REF: Load An Extension
1.4 misho 6543: ** METHOD: sqlite3
1.2 misho 6544: **
6545: ** ^This interface loads an SQLite extension library from the named file.
6546: **
6547: ** ^The sqlite3_load_extension() interface attempts to load an
1.4 misho 6548: ** [SQLite extension] library contained in the file zFile. If
6549: ** the file cannot be loaded directly, attempts are made to load
6550: ** with various operating-system specific extensions added.
6551: ** So for example, if "samplelib" cannot be loaded, then names like
6552: ** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
6553: ** be tried also.
1.2 misho 6554: **
6555: ** ^The entry point is zProc.
1.4 misho 6556: ** ^(zProc may be 0, in which case SQLite will try to come up with an
6557: ** entry point name on its own. It first tries "sqlite3_extension_init".
6558: ** If that does not work, it constructs a name "sqlite3_X_init" where the
6559: ** X is consists of the lower-case equivalent of all ASCII alphabetic
6560: ** characters in the filename from the last "/" to the first following
6561: ** "." and omitting any initial "lib".)^
1.2 misho 6562: ** ^The sqlite3_load_extension() interface returns
6563: ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
6564: ** ^If an error occurs and pzErrMsg is not 0, then the
6565: ** [sqlite3_load_extension()] interface shall attempt to
6566: ** fill *pzErrMsg with error message text stored in memory
6567: ** obtained from [sqlite3_malloc()]. The calling function
6568: ** should free this memory by calling [sqlite3_free()].
6569: **
6570: ** ^Extension loading must be enabled using
1.4 misho 6571: ** [sqlite3_enable_load_extension()] or
6572: ** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL)
6573: ** prior to calling this API,
1.2 misho 6574: ** otherwise an error will be returned.
6575: **
1.4.2.3 ! misho 6576: ** <b>Security warning:</b> It is recommended that the
1.4 misho 6577: ** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this
6578: ** interface. The use of the [sqlite3_enable_load_extension()] interface
6579: ** should be avoided. This will keep the SQL function [load_extension()]
6580: ** disabled and prevent SQL injections from giving attackers
6581: ** access to extension loading capabilities.
6582: **
1.2 misho 6583: ** See also the [load_extension() SQL function].
6584: */
6585: SQLITE_API int sqlite3_load_extension(
6586: sqlite3 *db, /* Load the extension into this database connection */
6587: const char *zFile, /* Name of the shared library containing extension */
6588: const char *zProc, /* Entry point. Derived from zFile if 0 */
6589: char **pzErrMsg /* Put error message here if not 0 */
6590: );
6591:
6592: /*
6593: ** CAPI3REF: Enable Or Disable Extension Loading
1.4 misho 6594: ** METHOD: sqlite3
1.2 misho 6595: **
6596: ** ^So as not to open security holes in older applications that are
1.4 misho 6597: ** unprepared to deal with [extension loading], and as a means of disabling
6598: ** [extension loading] while evaluating user-entered SQL, the following API
1.2 misho 6599: ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
6600: **
1.4 misho 6601: ** ^Extension loading is off by default.
1.2 misho 6602: ** ^Call the sqlite3_enable_load_extension() routine with onoff==1
6603: ** to turn extension loading on and call it with onoff==0 to turn
6604: ** it back off again.
1.4 misho 6605: **
6606: ** ^This interface enables or disables both the C-API
6607: ** [sqlite3_load_extension()] and the SQL function [load_extension()].
6608: ** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..)
6609: ** to enable or disable only the C-API.)^
6610: **
6611: ** <b>Security warning:</b> It is recommended that extension loading
1.4.2.3 ! misho 6612: ** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method
1.4 misho 6613: ** rather than this interface, so the [load_extension()] SQL function
6614: ** remains disabled. This will prevent SQL injections from giving attackers
6615: ** access to extension loading capabilities.
1.2 misho 6616: */
6617: SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
6618:
6619: /*
6620: ** CAPI3REF: Automatically Load Statically Linked Extensions
6621: **
6622: ** ^This interface causes the xEntryPoint() function to be invoked for
6623: ** each new [database connection] that is created. The idea here is that
1.4 misho 6624: ** xEntryPoint() is the entry point for a statically linked [SQLite extension]
1.2 misho 6625: ** that is to be automatically loaded into all new database connections.
6626: **
6627: ** ^(Even though the function prototype shows that xEntryPoint() takes
6628: ** no arguments and returns void, SQLite invokes xEntryPoint() with three
1.4 misho 6629: ** arguments and expects an integer result as if the signature of the
1.2 misho 6630: ** entry point where as follows:
6631: **
6632: ** <blockquote><pre>
6633: ** int xEntryPoint(
6634: ** sqlite3 *db,
6635: ** const char **pzErrMsg,
6636: ** const struct sqlite3_api_routines *pThunk
6637: ** );
6638: ** </pre></blockquote>)^
6639: **
6640: ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
6641: ** point to an appropriate error message (obtained from [sqlite3_mprintf()])
6642: ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg
6643: ** is NULL before calling the xEntryPoint(). ^SQLite will invoke
6644: ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any
6645: ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
6646: ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
6647: **
6648: ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
6649: ** on the list of automatic extensions is a harmless no-op. ^No entry point
6650: ** will be called more than once for each database connection that is opened.
6651: **
1.4 misho 6652: ** See also: [sqlite3_reset_auto_extension()]
6653: ** and [sqlite3_cancel_auto_extension()]
1.2 misho 6654: */
1.4 misho 6655: SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void));
6656:
6657: /*
6658: ** CAPI3REF: Cancel Automatic Extension Loading
6659: **
6660: ** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
6661: ** initialization routine X that was registered using a prior call to
6662: ** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)]
1.4.2.3 ! misho 6663: ** routine returns 1 if initialization routine X was successfully
1.4 misho 6664: ** unregistered and it returns 0 if X was not on the list of initialization
6665: ** routines.
6666: */
6667: SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void));
1.2 misho 6668:
6669: /*
6670: ** CAPI3REF: Reset Automatic Extension Loading
6671: **
6672: ** ^This interface disables all automatic extensions previously
6673: ** registered using [sqlite3_auto_extension()].
6674: */
6675: SQLITE_API void sqlite3_reset_auto_extension(void);
6676:
6677: /*
6678: ** The interface to the virtual-table mechanism is currently considered
6679: ** to be experimental. The interface might change in incompatible ways.
6680: ** If this is a problem for you, do not use the interface at this time.
6681: **
6682: ** When the virtual-table mechanism stabilizes, we will declare the
6683: ** interface fixed, support it indefinitely, and remove this comment.
6684: */
6685:
6686: /*
6687: ** Structures used by the virtual table interface
6688: */
6689: typedef struct sqlite3_vtab sqlite3_vtab;
6690: typedef struct sqlite3_index_info sqlite3_index_info;
6691: typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
6692: typedef struct sqlite3_module sqlite3_module;
6693:
6694: /*
6695: ** CAPI3REF: Virtual Table Object
6696: ** KEYWORDS: sqlite3_module {virtual table module}
6697: **
1.4.2.3 ! misho 6698: ** This structure, sometimes called a "virtual table module",
! 6699: ** defines the implementation of a [virtual table].
1.2 misho 6700: ** This structure consists mostly of methods for the module.
6701: **
6702: ** ^A virtual table module is created by filling in a persistent
6703: ** instance of this structure and passing a pointer to that instance
6704: ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
6705: ** ^The registration remains valid until it is replaced by a different
6706: ** module or until the [database connection] closes. The content
6707: ** of this structure must not change while it is registered with
6708: ** any database connection.
6709: */
6710: struct sqlite3_module {
6711: int iVersion;
6712: int (*xCreate)(sqlite3*, void *pAux,
6713: int argc, const char *const*argv,
6714: sqlite3_vtab **ppVTab, char**);
6715: int (*xConnect)(sqlite3*, void *pAux,
6716: int argc, const char *const*argv,
6717: sqlite3_vtab **ppVTab, char**);
6718: int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
6719: int (*xDisconnect)(sqlite3_vtab *pVTab);
6720: int (*xDestroy)(sqlite3_vtab *pVTab);
6721: int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
6722: int (*xClose)(sqlite3_vtab_cursor*);
6723: int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
6724: int argc, sqlite3_value **argv);
6725: int (*xNext)(sqlite3_vtab_cursor*);
6726: int (*xEof)(sqlite3_vtab_cursor*);
6727: int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
6728: int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
6729: int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
6730: int (*xBegin)(sqlite3_vtab *pVTab);
6731: int (*xSync)(sqlite3_vtab *pVTab);
6732: int (*xCommit)(sqlite3_vtab *pVTab);
6733: int (*xRollback)(sqlite3_vtab *pVTab);
6734: int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
6735: void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
6736: void **ppArg);
6737: int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
1.4.2.3 ! misho 6738: /* The methods above are in version 1 of the sqlite_module object. Those
1.2 misho 6739: ** below are for version 2 and greater. */
6740: int (*xSavepoint)(sqlite3_vtab *pVTab, int);
6741: int (*xRelease)(sqlite3_vtab *pVTab, int);
6742: int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
1.4.2.2 misho 6743: /* The methods above are in versions 1 and 2 of the sqlite_module object.
6744: ** Those below are for version 3 and greater. */
6745: int (*xShadowName)(const char*);
1.2 misho 6746: };
6747:
6748: /*
6749: ** CAPI3REF: Virtual Table Indexing Information
6750: ** KEYWORDS: sqlite3_index_info
6751: **
6752: ** The sqlite3_index_info structure and its substructures is used as part
6753: ** of the [virtual table] interface to
6754: ** pass information into and receive the reply from the [xBestIndex]
6755: ** method of a [virtual table module]. The fields under **Inputs** are the
6756: ** inputs to xBestIndex and are read-only. xBestIndex inserts its
6757: ** results into the **Outputs** fields.
6758: **
6759: ** ^(The aConstraint[] array records WHERE clause constraints of the form:
6760: **
6761: ** <blockquote>column OP expr</blockquote>
6762: **
6763: ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is
6764: ** stored in aConstraint[].op using one of the
6765: ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
6766: ** ^(The index of the column is stored in
6767: ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
6768: ** expr on the right-hand side can be evaluated (and thus the constraint
6769: ** is usable) and false if it cannot.)^
6770: **
6771: ** ^The optimizer automatically inverts terms of the form "expr OP column"
6772: ** and makes other simplifications to the WHERE clause in an attempt to
6773: ** get as many WHERE clause terms into the form shown above as possible.
6774: ** ^The aConstraint[] array only reports WHERE clause terms that are
6775: ** relevant to the particular virtual table being queried.
6776: **
6777: ** ^Information about the ORDER BY clause is stored in aOrderBy[].
6778: ** ^Each term of aOrderBy records a column of the ORDER BY clause.
6779: **
1.4 misho 6780: ** The colUsed field indicates which columns of the virtual table may be
6781: ** required by the current scan. Virtual table columns are numbered from
6782: ** zero in the order in which they appear within the CREATE TABLE statement
6783: ** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
6784: ** the corresponding bit is set within the colUsed mask if the column may be
6785: ** required by SQLite. If the table has at least 64 columns and any column
6786: ** to the right of the first 63 is required, then bit 63 of colUsed is also
6787: ** set. In other words, column iCol may be required if the expression
1.4.2.3 ! misho 6788: ** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to
1.4 misho 6789: ** non-zero.
6790: **
1.2 misho 6791: ** The [xBestIndex] method must fill aConstraintUsage[] with information
6792: ** about what parameters to pass to xFilter. ^If argvIndex>0 then
6793: ** the right-hand side of the corresponding aConstraint[] is evaluated
6794: ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
6795: ** is true, then the constraint is assumed to be fully handled by the
1.4.2.3 ! misho 6796: ** virtual table and might not be checked again by the byte code.)^ ^(The
! 6797: ** aConstraintUsage[].omit flag is an optimization hint. When the omit flag
! 6798: ** is left in its default setting of false, the constraint will always be
! 6799: ** checked separately in byte code. If the omit flag is change to true, then
! 6800: ** the constraint may or may not be checked in byte code. In other words,
! 6801: ** when the omit flag is true there is no guarantee that the constraint will
! 6802: ** not be checked again using byte code.)^
1.2 misho 6803: **
6804: ** ^The idxNum and idxPtr values are recorded and passed into the
6805: ** [xFilter] method.
6806: ** ^[sqlite3_free()] is used to free idxPtr if and only if
6807: ** needToFreeIdxPtr is true.
6808: **
6809: ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
6810: ** the correct order to satisfy the ORDER BY clause so that no separate
6811: ** sorting step is required.
6812: **
1.4 misho 6813: ** ^The estimatedCost value is an estimate of the cost of a particular
6814: ** strategy. A cost of N indicates that the cost of the strategy is similar
1.4.2.3 ! misho 6815: ** to a linear scan of an SQLite table with N rows. A cost of log(N)
1.4 misho 6816: ** indicates that the expense of the operation is similar to that of a
6817: ** binary search on a unique indexed field of an SQLite table with N rows.
6818: **
6819: ** ^The estimatedRows value is an estimate of the number of rows that
6820: ** will be returned by the strategy.
6821: **
1.4.2.3 ! misho 6822: ** The xBestIndex method may optionally populate the idxFlags field with a
1.4 misho 6823: ** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag -
6824: ** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite
1.4.2.3 ! misho 6825: ** assumes that the strategy may visit at most one row.
1.4 misho 6826: **
6827: ** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then
6828: ** SQLite also assumes that if a call to the xUpdate() method is made as
6829: ** part of the same statement to delete or update a virtual table row and the
6830: ** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback
6831: ** any database changes. In other words, if the xUpdate() returns
6832: ** SQLITE_CONSTRAINT, the database contents must be exactly as they were
6833: ** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not
6834: ** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by
6835: ** the xUpdate method are automatically rolled back by SQLite.
6836: **
6837: ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
1.4.2.3 ! misho 6838: ** structure for SQLite [version 3.8.2] ([dateof:3.8.2]).
1.4.2.1 misho 6839: ** If a virtual table extension is
1.4.2.3 ! misho 6840: ** used with an SQLite version earlier than 3.8.2, the results of attempting
! 6841: ** to read or write the estimatedRows field are undefined (but are likely
! 6842: ** to include crashing the application). The estimatedRows field should
1.4 misho 6843: ** therefore only be used if [sqlite3_libversion_number()] returns a
6844: ** value greater than or equal to 3008002. Similarly, the idxFlags field
1.4.2.3 ! misho 6845: ** was added for [version 3.9.0] ([dateof:3.9.0]).
1.4.2.1 misho 6846: ** It may therefore only be used if
1.4 misho 6847: ** sqlite3_libversion_number() returns a value greater than or equal to
6848: ** 3009000.
1.2 misho 6849: */
6850: struct sqlite3_index_info {
6851: /* Inputs */
6852: int nConstraint; /* Number of entries in aConstraint */
6853: struct sqlite3_index_constraint {
1.4 misho 6854: int iColumn; /* Column constrained. -1 for ROWID */
1.2 misho 6855: unsigned char op; /* Constraint operator */
6856: unsigned char usable; /* True if this constraint is usable */
6857: int iTermOffset; /* Used internally - xBestIndex should ignore */
6858: } *aConstraint; /* Table of WHERE clause constraints */
6859: int nOrderBy; /* Number of terms in the ORDER BY clause */
6860: struct sqlite3_index_orderby {
6861: int iColumn; /* Column number */
6862: unsigned char desc; /* True for DESC. False for ASC. */
6863: } *aOrderBy; /* The ORDER BY clause */
6864: /* Outputs */
6865: struct sqlite3_index_constraint_usage {
6866: int argvIndex; /* if >0, constraint is part of argv to xFilter */
6867: unsigned char omit; /* Do not code a test for this constraint */
6868: } *aConstraintUsage;
6869: int idxNum; /* Number used to identify the index */
6870: char *idxStr; /* String, possibly obtained from sqlite3_malloc */
6871: int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
6872: int orderByConsumed; /* True if output is already ordered */
1.4 misho 6873: double estimatedCost; /* Estimated cost of using this index */
6874: /* Fields below are only available in SQLite 3.8.2 and later */
6875: sqlite3_int64 estimatedRows; /* Estimated number of rows returned */
6876: /* Fields below are only available in SQLite 3.9.0 and later */
6877: int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */
6878: /* Fields below are only available in SQLite 3.10.0 and later */
6879: sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */
1.2 misho 6880: };
6881:
6882: /*
1.4 misho 6883: ** CAPI3REF: Virtual Table Scan Flags
1.4.2.2 misho 6884: **
1.4.2.3 ! misho 6885: ** Virtual table implementations are allowed to set the
1.4.2.2 misho 6886: ** [sqlite3_index_info].idxFlags field to some combination of
6887: ** these bits.
1.4 misho 6888: */
6889: #define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */
6890:
6891: /*
1.2 misho 6892: ** CAPI3REF: Virtual Table Constraint Operator Codes
6893: **
1.4.2.3 ! misho 6894: ** These macros define the allowed values for the
1.2 misho 6895: ** [sqlite3_index_info].aConstraint[].op field. Each value represents
6896: ** an operator that is part of a constraint term in the wHERE clause of
6897: ** a query that uses a [virtual table].
6898: */
1.4.2.2 misho 6899: #define SQLITE_INDEX_CONSTRAINT_EQ 2
6900: #define SQLITE_INDEX_CONSTRAINT_GT 4
6901: #define SQLITE_INDEX_CONSTRAINT_LE 8
6902: #define SQLITE_INDEX_CONSTRAINT_LT 16
6903: #define SQLITE_INDEX_CONSTRAINT_GE 32
6904: #define SQLITE_INDEX_CONSTRAINT_MATCH 64
6905: #define SQLITE_INDEX_CONSTRAINT_LIKE 65
6906: #define SQLITE_INDEX_CONSTRAINT_GLOB 66
6907: #define SQLITE_INDEX_CONSTRAINT_REGEXP 67
6908: #define SQLITE_INDEX_CONSTRAINT_NE 68
6909: #define SQLITE_INDEX_CONSTRAINT_ISNOT 69
6910: #define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70
6911: #define SQLITE_INDEX_CONSTRAINT_ISNULL 71
6912: #define SQLITE_INDEX_CONSTRAINT_IS 72
6913: #define SQLITE_INDEX_CONSTRAINT_FUNCTION 150
1.2 misho 6914:
6915: /*
6916: ** CAPI3REF: Register A Virtual Table Implementation
1.4 misho 6917: ** METHOD: sqlite3
1.2 misho 6918: **
6919: ** ^These routines are used to register a new [virtual table module] name.
6920: ** ^Module names must be registered before
6921: ** creating a new [virtual table] using the module and before using a
6922: ** preexisting [virtual table] for the module.
6923: **
6924: ** ^The module name is registered on the [database connection] specified
1.4.2.3 ! misho 6925: ** by the first parameter. ^The name of the module is given by the
1.2 misho 6926: ** second parameter. ^The third parameter is a pointer to
6927: ** the implementation of the [virtual table module]. ^The fourth
6928: ** parameter is an arbitrary client data pointer that is passed through
6929: ** into the [xCreate] and [xConnect] methods of the virtual table module
6930: ** when a new virtual table is be being created or reinitialized.
6931: **
6932: ** ^The sqlite3_create_module_v2() interface has a fifth parameter which
6933: ** is a pointer to a destructor for the pClientData. ^SQLite will
6934: ** invoke the destructor function (if it is not NULL) when SQLite
6935: ** no longer needs the pClientData pointer. ^The destructor will also
6936: ** be invoked if the call to sqlite3_create_module_v2() fails.
6937: ** ^The sqlite3_create_module()
6938: ** interface is equivalent to sqlite3_create_module_v2() with a NULL
6939: ** destructor.
1.4.2.3 ! misho 6940: **
! 6941: ** ^If the third parameter (the pointer to the sqlite3_module object) is
! 6942: ** NULL then no new module is create and any existing modules with the
! 6943: ** same name are dropped.
! 6944: **
! 6945: ** See also: [sqlite3_drop_modules()]
1.2 misho 6946: */
6947: SQLITE_API int sqlite3_create_module(
6948: sqlite3 *db, /* SQLite connection to register module with */
6949: const char *zName, /* Name of the module */
6950: const sqlite3_module *p, /* Methods for the module */
6951: void *pClientData /* Client data for xCreate/xConnect */
6952: );
6953: SQLITE_API int sqlite3_create_module_v2(
6954: sqlite3 *db, /* SQLite connection to register module with */
6955: const char *zName, /* Name of the module */
6956: const sqlite3_module *p, /* Methods for the module */
6957: void *pClientData, /* Client data for xCreate/xConnect */
6958: void(*xDestroy)(void*) /* Module destructor function */
6959: );
6960:
6961: /*
1.4.2.3 ! misho 6962: ** CAPI3REF: Remove Unnecessary Virtual Table Implementations
! 6963: ** METHOD: sqlite3
! 6964: **
! 6965: ** ^The sqlite3_drop_modules(D,L) interface removes all virtual
! 6966: ** table modules from database connection D except those named on list L.
! 6967: ** The L parameter must be either NULL or a pointer to an array of pointers
! 6968: ** to strings where the array is terminated by a single NULL pointer.
! 6969: ** ^If the L parameter is NULL, then all virtual table modules are removed.
! 6970: **
! 6971: ** See also: [sqlite3_create_module()]
! 6972: */
! 6973: SQLITE_API int sqlite3_drop_modules(
! 6974: sqlite3 *db, /* Remove modules from this connection */
! 6975: const char **azKeep /* Except, do not remove the ones named here */
! 6976: );
! 6977:
! 6978: /*
1.2 misho 6979: ** CAPI3REF: Virtual Table Instance Object
6980: ** KEYWORDS: sqlite3_vtab
6981: **
6982: ** Every [virtual table module] implementation uses a subclass
6983: ** of this object to describe a particular instance
6984: ** of the [virtual table]. Each subclass will
6985: ** be tailored to the specific needs of the module implementation.
6986: ** The purpose of this superclass is to define certain fields that are
6987: ** common to all module implementations.
6988: **
6989: ** ^Virtual tables methods can set an error message by assigning a
6990: ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
6991: ** take care that any prior string is freed by a call to [sqlite3_free()]
6992: ** prior to assigning a new string to zErrMsg. ^After the error message
6993: ** is delivered up to the client application, the string will be automatically
6994: ** freed by sqlite3_free() and the zErrMsg field will be zeroed.
6995: */
6996: struct sqlite3_vtab {
6997: const sqlite3_module *pModule; /* The module for this virtual table */
1.4 misho 6998: int nRef; /* Number of open cursors */
1.2 misho 6999: char *zErrMsg; /* Error message from sqlite3_mprintf() */
7000: /* Virtual table implementations will typically add additional fields */
7001: };
7002:
7003: /*
7004: ** CAPI3REF: Virtual Table Cursor Object
7005: ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
7006: **
7007: ** Every [virtual table module] implementation uses a subclass of the
7008: ** following structure to describe cursors that point into the
7009: ** [virtual table] and are used
7010: ** to loop through the virtual table. Cursors are created using the
7011: ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
7012: ** by the [sqlite3_module.xClose | xClose] method. Cursors are used
7013: ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
7014: ** of the module. Each module implementation will define
7015: ** the content of a cursor structure to suit its own needs.
7016: **
7017: ** This superclass exists in order to define fields of the cursor that
7018: ** are common to all implementations.
7019: */
7020: struct sqlite3_vtab_cursor {
7021: sqlite3_vtab *pVtab; /* Virtual table of this cursor */
7022: /* Virtual table implementations will typically add additional fields */
7023: };
7024:
7025: /*
7026: ** CAPI3REF: Declare The Schema Of A Virtual Table
7027: **
7028: ** ^The [xCreate] and [xConnect] methods of a
7029: ** [virtual table module] call this interface
7030: ** to declare the format (the names and datatypes of the columns) of
7031: ** the virtual tables they implement.
7032: */
7033: SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
7034:
7035: /*
7036: ** CAPI3REF: Overload A Function For A Virtual Table
1.4 misho 7037: ** METHOD: sqlite3
1.2 misho 7038: **
7039: ** ^(Virtual tables can provide alternative implementations of functions
1.4.2.3 ! misho 7040: ** using the [xFindFunction] method of the [virtual table module].
1.2 misho 7041: ** But global versions of those functions
7042: ** must exist in order to be overloaded.)^
7043: **
7044: ** ^(This API makes sure a global version of a function with a particular
7045: ** name and number of parameters exists. If no such function exists
7046: ** before this API is called, a new function is created.)^ ^The implementation
7047: ** of the new function always causes an exception to be thrown. So
7048: ** the new function is not good for anything by itself. Its only
7049: ** purpose is to be a placeholder function that can be overloaded
7050: ** by a [virtual table].
7051: */
7052: SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
7053:
7054: /*
7055: ** The interface to the virtual-table mechanism defined above (back up
7056: ** to a comment remarkably similar to this one) is currently considered
7057: ** to be experimental. The interface might change in incompatible ways.
7058: ** If this is a problem for you, do not use the interface at this time.
7059: **
7060: ** When the virtual-table mechanism stabilizes, we will declare the
7061: ** interface fixed, support it indefinitely, and remove this comment.
7062: */
7063:
7064: /*
7065: ** CAPI3REF: A Handle To An Open BLOB
7066: ** KEYWORDS: {BLOB handle} {BLOB handles}
7067: **
7068: ** An instance of this object represents an open BLOB on which
7069: ** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
7070: ** ^Objects of this type are created by [sqlite3_blob_open()]
7071: ** and destroyed by [sqlite3_blob_close()].
7072: ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
7073: ** can be used to read or write small subsections of the BLOB.
7074: ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
7075: */
7076: typedef struct sqlite3_blob sqlite3_blob;
7077:
7078: /*
7079: ** CAPI3REF: Open A BLOB For Incremental I/O
1.4 misho 7080: ** METHOD: sqlite3
7081: ** CONSTRUCTOR: sqlite3_blob
1.2 misho 7082: **
7083: ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
7084: ** in row iRow, column zColumn, table zTable in database zDb;
7085: ** in other words, the same BLOB that would be selected by:
7086: **
7087: ** <pre>
7088: ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
7089: ** </pre>)^
7090: **
1.4.2.3 ! misho 7091: ** ^(Parameter zDb is not the filename that contains the database, but
1.4 misho 7092: ** rather the symbolic name of the database. For attached databases, this is
7093: ** the name that appears after the AS keyword in the [ATTACH] statement.
7094: ** For the main database file, the database name is "main". For TEMP
7095: ** tables, the database name is "temp".)^
7096: **
1.2 misho 7097: ** ^If the flags parameter is non-zero, then the BLOB is opened for read
1.4 misho 7098: ** and write access. ^If the flags parameter is zero, the BLOB is opened for
7099: ** read-only access.
7100: **
7101: ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored
7102: ** in *ppBlob. Otherwise an [error code] is returned and, unless the error
7103: ** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided
1.4.2.3 ! misho 7104: ** the API is not misused, it is always safe to call [sqlite3_blob_close()]
1.4 misho 7105: ** on *ppBlob after this function it returns.
7106: **
7107: ** This function fails with SQLITE_ERROR if any of the following are true:
7108: ** <ul>
1.4.2.3 ! misho 7109: ** <li> ^(Database zDb does not exist)^,
! 7110: ** <li> ^(Table zTable does not exist within database zDb)^,
! 7111: ** <li> ^(Table zTable is a WITHOUT ROWID table)^,
1.4 misho 7112: ** <li> ^(Column zColumn does not exist)^,
7113: ** <li> ^(Row iRow is not present in the table)^,
7114: ** <li> ^(The specified column of row iRow contains a value that is not
7115: ** a TEXT or BLOB value)^,
1.4.2.3 ! misho 7116: ** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE
1.4 misho 7117: ** constraint and the blob is being opened for read/write access)^,
1.4.2.3 ! misho 7118: ** <li> ^([foreign key constraints | Foreign key constraints] are enabled,
1.4 misho 7119: ** column zColumn is part of a [child key] definition and the blob is
7120: ** being opened for read/write access)^.
7121: ** </ul>
7122: **
1.4.2.3 ! misho 7123: ** ^Unless it returns SQLITE_MISUSE, this function sets the
! 7124: ** [database connection] error code and message accessible via
! 7125: ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
1.4 misho 7126: **
1.4.2.1 misho 7127: ** A BLOB referenced by sqlite3_blob_open() may be read using the
7128: ** [sqlite3_blob_read()] interface and modified by using
7129: ** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a
7130: ** different row of the same table using the [sqlite3_blob_reopen()]
7131: ** interface. However, the column, table, or database of a [BLOB handle]
7132: ** cannot be changed after the [BLOB handle] is opened.
1.2 misho 7133: **
7134: ** ^(If the row that a BLOB handle points to is modified by an
7135: ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
7136: ** then the BLOB handle is marked as "expired".
7137: ** This is true if any column of the row is changed, even a column
7138: ** other than the one the BLOB handle is open on.)^
7139: ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
7140: ** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
7141: ** ^(Changes written into a BLOB prior to the BLOB expiring are not
7142: ** rolled back by the expiration of the BLOB. Such changes will eventually
7143: ** commit if the transaction continues to completion.)^
7144: **
7145: ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
7146: ** the opened blob. ^The size of a blob may not be changed by this
7147: ** interface. Use the [UPDATE] SQL command to change the size of a
7148: ** blob.
7149: **
7150: ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
1.4.2.3 ! misho 7151: ** and the built-in [zeroblob] SQL function may be used to create a
1.4 misho 7152: ** zero-filled blob to read or write using the incremental-blob interface.
1.2 misho 7153: **
7154: ** To avoid a resource leak, every open [BLOB handle] should eventually
7155: ** be released by a call to [sqlite3_blob_close()].
1.4.2.1 misho 7156: **
7157: ** See also: [sqlite3_blob_close()],
7158: ** [sqlite3_blob_reopen()], [sqlite3_blob_read()],
7159: ** [sqlite3_blob_bytes()], [sqlite3_blob_write()].
1.2 misho 7160: */
7161: SQLITE_API int sqlite3_blob_open(
7162: sqlite3*,
7163: const char *zDb,
7164: const char *zTable,
7165: const char *zColumn,
7166: sqlite3_int64 iRow,
7167: int flags,
7168: sqlite3_blob **ppBlob
7169: );
7170:
7171: /*
7172: ** CAPI3REF: Move a BLOB Handle to a New Row
1.4 misho 7173: ** METHOD: sqlite3_blob
1.2 misho 7174: **
1.4.2.1 misho 7175: ** ^This function is used to move an existing [BLOB handle] so that it points
1.2 misho 7176: ** to a different row of the same database table. ^The new row is identified
7177: ** by the rowid value passed as the second argument. Only the row can be
7178: ** changed. ^The database, table and column on which the blob handle is open
1.4.2.1 misho 7179: ** remain the same. Moving an existing [BLOB handle] to a new row is
1.2 misho 7180: ** faster than closing the existing handle and opening a new one.
7181: **
7182: ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
7183: ** it must exist and there must be either a blob or text value stored in
7184: ** the nominated column.)^ ^If the new row is not present in the table, or if
7185: ** it does not contain a blob or text value, or if another error occurs, an
7186: ** SQLite error code is returned and the blob handle is considered aborted.
7187: ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
7188: ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
7189: ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
7190: ** always returns zero.
7191: **
7192: ** ^This function sets the database handle error code and message.
7193: */
1.4 misho 7194: SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
1.2 misho 7195:
7196: /*
7197: ** CAPI3REF: Close A BLOB Handle
1.4 misho 7198: ** DESTRUCTOR: sqlite3_blob
1.2 misho 7199: **
1.4 misho 7200: ** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed
1.4.2.3 ! misho 7201: ** unconditionally. Even if this routine returns an error code, the
1.4 misho 7202: ** handle is still closed.)^
7203: **
7204: ** ^If the blob handle being closed was opened for read-write access, and if
7205: ** the database is in auto-commit mode and there are no other open read-write
7206: ** blob handles or active write statements, the current transaction is
7207: ** committed. ^If an error occurs while committing the transaction, an error
7208: ** code is returned and the transaction rolled back.
7209: **
7210: ** Calling this function with an argument that is not a NULL pointer or an
1.4.2.3 ! misho 7211: ** open blob handle results in undefined behaviour. ^Calling this routine
! 7212: ** with a null pointer (such as would be returned by a failed call to
1.4 misho 7213: ** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
1.4.2.3 ! misho 7214: ** is passed a valid open blob handle, the values returned by the
1.4 misho 7215: ** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
1.2 misho 7216: */
7217: SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
7218:
7219: /*
7220: ** CAPI3REF: Return The Size Of An Open BLOB
1.4 misho 7221: ** METHOD: sqlite3_blob
1.2 misho 7222: **
1.4.2.3 ! misho 7223: ** ^Returns the size in bytes of the BLOB accessible via the
1.2 misho 7224: ** successfully opened [BLOB handle] in its only argument. ^The
7225: ** incremental blob I/O routines can only read or overwriting existing
7226: ** blob content; they cannot change the size of a blob.
7227: **
7228: ** This routine only works on a [BLOB handle] which has been created
7229: ** by a prior successful call to [sqlite3_blob_open()] and which has not
7230: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
7231: ** to this routine results in undefined and probably undesirable behavior.
7232: */
7233: SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
7234:
7235: /*
7236: ** CAPI3REF: Read Data From A BLOB Incrementally
1.4 misho 7237: ** METHOD: sqlite3_blob
1.2 misho 7238: **
7239: ** ^(This function is used to read data from an open [BLOB handle] into a
7240: ** caller-supplied buffer. N bytes of data are copied into buffer Z
7241: ** from the open BLOB, starting at offset iOffset.)^
7242: **
7243: ** ^If offset iOffset is less than N bytes from the end of the BLOB,
7244: ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
7245: ** less than zero, [SQLITE_ERROR] is returned and no data is read.
7246: ** ^The size of the blob (and hence the maximum value of N+iOffset)
7247: ** can be determined using the [sqlite3_blob_bytes()] interface.
7248: **
7249: ** ^An attempt to read from an expired [BLOB handle] fails with an
7250: ** error code of [SQLITE_ABORT].
7251: **
7252: ** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
7253: ** Otherwise, an [error code] or an [extended error code] is returned.)^
7254: **
7255: ** This routine only works on a [BLOB handle] which has been created
7256: ** by a prior successful call to [sqlite3_blob_open()] and which has not
7257: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
7258: ** to this routine results in undefined and probably undesirable behavior.
7259: **
7260: ** See also: [sqlite3_blob_write()].
7261: */
7262: SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
7263:
7264: /*
7265: ** CAPI3REF: Write Data Into A BLOB Incrementally
1.4 misho 7266: ** METHOD: sqlite3_blob
1.2 misho 7267: **
1.4 misho 7268: ** ^(This function is used to write data into an open [BLOB handle] from a
7269: ** caller-supplied buffer. N bytes of data are copied from the buffer Z
7270: ** into the open BLOB, starting at offset iOffset.)^
7271: **
7272: ** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
7273: ** Otherwise, an [error code] or an [extended error code] is returned.)^
1.4.2.3 ! misho 7274: ** ^Unless SQLITE_MISUSE is returned, this function sets the
! 7275: ** [database connection] error code and message accessible via
! 7276: ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
1.2 misho 7277: **
7278: ** ^If the [BLOB handle] passed as the first argument was not opened for
7279: ** writing (the flags parameter to [sqlite3_blob_open()] was zero),
7280: ** this function returns [SQLITE_READONLY].
7281: **
1.4 misho 7282: ** This function may only modify the contents of the BLOB; it is
1.2 misho 7283: ** not possible to increase the size of a BLOB using this API.
7284: ** ^If offset iOffset is less than N bytes from the end of the BLOB,
1.4.2.3 ! misho 7285: ** [SQLITE_ERROR] is returned and no data is written. The size of the
! 7286: ** BLOB (and hence the maximum value of N+iOffset) can be determined
! 7287: ** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less
1.4 misho 7288: ** than zero [SQLITE_ERROR] is returned and no data is written.
1.2 misho 7289: **
7290: ** ^An attempt to write to an expired [BLOB handle] fails with an
7291: ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
7292: ** before the [BLOB handle] expired are not rolled back by the
7293: ** expiration of the handle, though of course those changes might
7294: ** have been overwritten by the statement that expired the BLOB handle
7295: ** or by other independent statements.
7296: **
7297: ** This routine only works on a [BLOB handle] which has been created
7298: ** by a prior successful call to [sqlite3_blob_open()] and which has not
7299: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
7300: ** to this routine results in undefined and probably undesirable behavior.
7301: **
7302: ** See also: [sqlite3_blob_read()].
7303: */
7304: SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
7305:
7306: /*
7307: ** CAPI3REF: Virtual File System Objects
7308: **
7309: ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
7310: ** that SQLite uses to interact
7311: ** with the underlying operating system. Most SQLite builds come with a
7312: ** single default VFS that is appropriate for the host computer.
7313: ** New VFSes can be registered and existing VFSes can be unregistered.
7314: ** The following interfaces are provided.
7315: **
7316: ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
7317: ** ^Names are case sensitive.
7318: ** ^Names are zero-terminated UTF-8 strings.
7319: ** ^If there is no match, a NULL pointer is returned.
7320: ** ^If zVfsName is NULL then the default VFS is returned.
7321: **
7322: ** ^New VFSes are registered with sqlite3_vfs_register().
7323: ** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
7324: ** ^The same VFS can be registered multiple times without injury.
7325: ** ^To make an existing VFS into the default VFS, register it again
7326: ** with the makeDflt flag set. If two different VFSes with the
7327: ** same name are registered, the behavior is undefined. If a
7328: ** VFS is registered with a name that is NULL or an empty string,
7329: ** then the behavior is undefined.
7330: **
7331: ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
7332: ** ^(If the default VFS is unregistered, another VFS is chosen as
7333: ** the default. The choice for the new VFS is arbitrary.)^
7334: */
7335: SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
7336: SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
7337: SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
7338:
7339: /*
7340: ** CAPI3REF: Mutexes
7341: **
7342: ** The SQLite core uses these routines for thread
7343: ** synchronization. Though they are intended for internal
7344: ** use by SQLite, code that links against SQLite is
7345: ** permitted to use any of these routines.
7346: **
7347: ** The SQLite source code contains multiple implementations
7348: ** of these mutex routines. An appropriate implementation
1.4 misho 7349: ** is selected automatically at compile-time. The following
1.2 misho 7350: ** implementations are available in the SQLite core:
7351: **
7352: ** <ul>
7353: ** <li> SQLITE_MUTEX_PTHREADS
7354: ** <li> SQLITE_MUTEX_W32
7355: ** <li> SQLITE_MUTEX_NOOP
1.4 misho 7356: ** </ul>
1.2 misho 7357: **
1.4 misho 7358: ** The SQLITE_MUTEX_NOOP implementation is a set of routines
1.2 misho 7359: ** that does no real locking and is appropriate for use in
1.4 misho 7360: ** a single-threaded application. The SQLITE_MUTEX_PTHREADS and
1.3 misho 7361: ** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
7362: ** and Windows.
1.2 misho 7363: **
1.4 misho 7364: ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
1.2 misho 7365: ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
7366: ** implementation is included with the library. In this case the
7367: ** application must supply a custom mutex implementation using the
7368: ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
7369: ** before calling sqlite3_initialize() or any other public sqlite3_
1.4 misho 7370: ** function that calls sqlite3_initialize().
1.2 misho 7371: **
7372: ** ^The sqlite3_mutex_alloc() routine allocates a new
1.4 misho 7373: ** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()
7374: ** routine returns NULL if it is unable to allocate the requested
7375: ** mutex. The argument to sqlite3_mutex_alloc() must one of these
7376: ** integer constants:
1.2 misho 7377: **
7378: ** <ul>
7379: ** <li> SQLITE_MUTEX_FAST
7380: ** <li> SQLITE_MUTEX_RECURSIVE
1.4.2.3 ! misho 7381: ** <li> SQLITE_MUTEX_STATIC_MAIN
1.2 misho 7382: ** <li> SQLITE_MUTEX_STATIC_MEM
1.4 misho 7383: ** <li> SQLITE_MUTEX_STATIC_OPEN
1.2 misho 7384: ** <li> SQLITE_MUTEX_STATIC_PRNG
7385: ** <li> SQLITE_MUTEX_STATIC_LRU
1.4 misho 7386: ** <li> SQLITE_MUTEX_STATIC_PMEM
7387: ** <li> SQLITE_MUTEX_STATIC_APP1
7388: ** <li> SQLITE_MUTEX_STATIC_APP2
7389: ** <li> SQLITE_MUTEX_STATIC_APP3
7390: ** <li> SQLITE_MUTEX_STATIC_VFS1
7391: ** <li> SQLITE_MUTEX_STATIC_VFS2
7392: ** <li> SQLITE_MUTEX_STATIC_VFS3
7393: ** </ul>
1.2 misho 7394: **
7395: ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
7396: ** cause sqlite3_mutex_alloc() to create
7397: ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
7398: ** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
7399: ** The mutex implementation does not need to make a distinction
7400: ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
1.4 misho 7401: ** not want to. SQLite will only request a recursive mutex in
7402: ** cases where it really needs one. If a faster non-recursive mutex
1.2 misho 7403: ** implementation is available on the host platform, the mutex subsystem
7404: ** might return such a mutex in response to SQLITE_MUTEX_FAST.
7405: **
7406: ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
7407: ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
1.4 misho 7408: ** a pointer to a static preexisting mutex. ^Nine static mutexes are
1.2 misho 7409: ** used by the current version of SQLite. Future versions of SQLite
7410: ** may add additional static mutexes. Static mutexes are for internal
7411: ** use by SQLite only. Applications that use SQLite mutexes should
7412: ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
7413: ** SQLITE_MUTEX_RECURSIVE.
7414: **
7415: ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
7416: ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
1.4 misho 7417: ** returns a different mutex on every call. ^For the static
1.2 misho 7418: ** mutex types, the same mutex is returned on every call that has
7419: ** the same type number.
7420: **
7421: ** ^The sqlite3_mutex_free() routine deallocates a previously
1.4 misho 7422: ** allocated dynamic mutex. Attempting to deallocate a static
7423: ** mutex results in undefined behavior.
1.2 misho 7424: **
7425: ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
7426: ** to enter a mutex. ^If another thread is already within the mutex,
7427: ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
7428: ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
7429: ** upon successful entry. ^(Mutexes created using
7430: ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
1.4 misho 7431: ** In such cases, the
1.2 misho 7432: ** mutex must be exited an equal number of times before another thread
1.4 misho 7433: ** can enter.)^ If the same thread tries to enter any mutex other
7434: ** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.
1.2 misho 7435: **
7436: ** ^(Some systems (for example, Windows 95) do not support the operation
7437: ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
1.4 misho 7438: ** will always return SQLITE_BUSY. The SQLite core only ever uses
1.4.2.3 ! misho 7439: ** sqlite3_mutex_try() as an optimization so this is acceptable
1.4 misho 7440: ** behavior.)^
1.2 misho 7441: **
7442: ** ^The sqlite3_mutex_leave() routine exits a mutex that was
1.4 misho 7443: ** previously entered by the same thread. The behavior
1.2 misho 7444: ** is undefined if the mutex is not currently entered by the
1.4 misho 7445: ** calling thread or is not currently allocated.
1.2 misho 7446: **
7447: ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
7448: ** sqlite3_mutex_leave() is a NULL pointer, then all three routines
7449: ** behave as no-ops.
7450: **
7451: ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
7452: */
7453: SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
7454: SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
7455: SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
7456: SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
7457: SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
7458:
7459: /*
7460: ** CAPI3REF: Mutex Methods Object
7461: **
7462: ** An instance of this structure defines the low-level routines
7463: ** used to allocate and use mutexes.
7464: **
7465: ** Usually, the default mutex implementations provided by SQLite are
1.4 misho 7466: ** sufficient, however the application has the option of substituting a custom
1.2 misho 7467: ** implementation for specialized deployments or systems for which SQLite
1.4 misho 7468: ** does not provide a suitable implementation. In this case, the application
1.2 misho 7469: ** creates and populates an instance of this structure to pass
7470: ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
7471: ** Additionally, an instance of this structure can be used as an
7472: ** output variable when querying the system for the current mutex
7473: ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
7474: **
7475: ** ^The xMutexInit method defined by this structure is invoked as
7476: ** part of system initialization by the sqlite3_initialize() function.
7477: ** ^The xMutexInit routine is called by SQLite exactly once for each
7478: ** effective call to [sqlite3_initialize()].
7479: **
7480: ** ^The xMutexEnd method defined by this structure is invoked as
7481: ** part of system shutdown by the sqlite3_shutdown() function. The
7482: ** implementation of this method is expected to release all outstanding
7483: ** resources obtained by the mutex methods implementation, especially
7484: ** those obtained by the xMutexInit method. ^The xMutexEnd()
7485: ** interface is invoked exactly once for each call to [sqlite3_shutdown()].
7486: **
7487: ** ^(The remaining seven methods defined by this structure (xMutexAlloc,
7488: ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
7489: ** xMutexNotheld) implement the following interfaces (respectively):
7490: **
7491: ** <ul>
7492: ** <li> [sqlite3_mutex_alloc()] </li>
7493: ** <li> [sqlite3_mutex_free()] </li>
7494: ** <li> [sqlite3_mutex_enter()] </li>
7495: ** <li> [sqlite3_mutex_try()] </li>
7496: ** <li> [sqlite3_mutex_leave()] </li>
7497: ** <li> [sqlite3_mutex_held()] </li>
7498: ** <li> [sqlite3_mutex_notheld()] </li>
7499: ** </ul>)^
7500: **
7501: ** The only difference is that the public sqlite3_XXX functions enumerated
7502: ** above silently ignore any invocations that pass a NULL pointer instead
7503: ** of a valid mutex handle. The implementations of the methods defined
1.4.2.3 ! misho 7504: ** by this structure are not required to handle this case. The results
1.2 misho 7505: ** of passing a NULL pointer instead of a valid mutex handle are undefined
7506: ** (i.e. it is acceptable to provide an implementation that segfaults if
7507: ** it is passed a NULL pointer).
7508: **
1.4 misho 7509: ** The xMutexInit() method must be threadsafe. It must be harmless to
1.2 misho 7510: ** invoke xMutexInit() multiple times within the same process and without
7511: ** intervening calls to xMutexEnd(). Second and subsequent calls to
7512: ** xMutexInit() must be no-ops.
7513: **
1.4 misho 7514: ** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
7515: ** and its associates). Similarly, xMutexAlloc() must not use SQLite memory
1.2 misho 7516: ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
7517: ** memory allocation for a fast or recursive mutex.
7518: **
7519: ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
7520: ** called, but only if the prior call to xMutexInit returned SQLITE_OK.
7521: ** If xMutexInit fails in any way, it is expected to clean up after itself
7522: ** prior to returning.
7523: */
7524: typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
7525: struct sqlite3_mutex_methods {
7526: int (*xMutexInit)(void);
7527: int (*xMutexEnd)(void);
7528: sqlite3_mutex *(*xMutexAlloc)(int);
7529: void (*xMutexFree)(sqlite3_mutex *);
7530: void (*xMutexEnter)(sqlite3_mutex *);
7531: int (*xMutexTry)(sqlite3_mutex *);
7532: void (*xMutexLeave)(sqlite3_mutex *);
7533: int (*xMutexHeld)(sqlite3_mutex *);
7534: int (*xMutexNotheld)(sqlite3_mutex *);
7535: };
7536:
7537: /*
7538: ** CAPI3REF: Mutex Verification Routines
7539: **
7540: ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
1.4 misho 7541: ** are intended for use inside assert() statements. The SQLite core
1.2 misho 7542: ** never uses these routines except inside an assert() and applications
1.4 misho 7543: ** are advised to follow the lead of the core. The SQLite core only
1.2 misho 7544: ** provides implementations for these routines when it is compiled
1.4 misho 7545: ** with the SQLITE_DEBUG flag. External mutex implementations
1.2 misho 7546: ** are only required to provide these routines if SQLITE_DEBUG is
7547: ** defined and if NDEBUG is not defined.
7548: **
1.4 misho 7549: ** These routines should return true if the mutex in their argument
1.2 misho 7550: ** is held or not held, respectively, by the calling thread.
7551: **
1.4 misho 7552: ** The implementation is not required to provide versions of these
1.2 misho 7553: ** routines that actually work. If the implementation does not provide working
7554: ** versions of these routines, it should at least provide stubs that always
7555: ** return true so that one does not get spurious assertion failures.
7556: **
1.4 misho 7557: ** If the argument to sqlite3_mutex_held() is a NULL pointer then
1.2 misho 7558: ** the routine should return 1. This seems counter-intuitive since
7559: ** clearly the mutex cannot be held if it does not exist. But
7560: ** the reason the mutex does not exist is because the build is not
7561: ** using mutexes. And we do not want the assert() containing the
7562: ** call to sqlite3_mutex_held() to fail, so a non-zero return is
1.4 misho 7563: ** the appropriate thing to do. The sqlite3_mutex_notheld()
1.2 misho 7564: ** interface should also return 1 when given a NULL pointer.
7565: */
7566: #ifndef NDEBUG
7567: SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
7568: SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
7569: #endif
7570:
7571: /*
7572: ** CAPI3REF: Mutex Types
7573: **
7574: ** The [sqlite3_mutex_alloc()] interface takes a single argument
7575: ** which is one of these integer constants.
7576: **
7577: ** The set of static mutexes may change from one SQLite release to the
7578: ** next. Applications that override the built-in mutex logic must be
7579: ** prepared to accommodate additional static mutexes.
7580: */
7581: #define SQLITE_MUTEX_FAST 0
7582: #define SQLITE_MUTEX_RECURSIVE 1
1.4.2.3 ! misho 7583: #define SQLITE_MUTEX_STATIC_MAIN 2
1.2 misho 7584: #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
7585: #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
7586: #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
1.4.2.1 misho 7587: #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */
1.2 misho 7588: #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
7589: #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */
7590: #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */
1.4 misho 7591: #define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */
7592: #define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */
7593: #define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */
7594: #define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */
7595: #define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */
7596: #define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */
1.2 misho 7597:
1.4.2.3 ! misho 7598: /* Legacy compatibility: */
! 7599: #define SQLITE_MUTEX_STATIC_MASTER 2
! 7600:
! 7601:
1.2 misho 7602: /*
7603: ** CAPI3REF: Retrieve the mutex for a database connection
1.4 misho 7604: ** METHOD: sqlite3
1.2 misho 7605: **
1.4.2.3 ! misho 7606: ** ^This interface returns a pointer the [sqlite3_mutex] object that
1.2 misho 7607: ** serializes access to the [database connection] given in the argument
7608: ** when the [threading mode] is Serialized.
7609: ** ^If the [threading mode] is Single-thread or Multi-thread then this
7610: ** routine returns a NULL pointer.
7611: */
7612: SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
7613:
7614: /*
7615: ** CAPI3REF: Low-Level Control Of Database Files
1.4 misho 7616: ** METHOD: sqlite3
1.4.2.2 misho 7617: ** KEYWORDS: {file control}
1.2 misho 7618: **
7619: ** ^The [sqlite3_file_control()] interface makes a direct call to the
7620: ** xFileControl method for the [sqlite3_io_methods] object associated
7621: ** with a particular database identified by the second argument. ^The
7622: ** name of the database is "main" for the main database or "temp" for the
7623: ** TEMP database, or the name that appears after the AS keyword for
7624: ** databases that are added using the [ATTACH] SQL command.
7625: ** ^A NULL pointer can be used in place of "main" to refer to the
7626: ** main database file.
7627: ** ^The third and fourth parameters to this routine
7628: ** are passed directly through to the second and third parameters of
7629: ** the xFileControl method. ^The return value of the xFileControl
7630: ** method becomes the return value of this routine.
7631: **
1.4.2.2 misho 7632: ** A few opcodes for [sqlite3_file_control()] are handled directly
1.4.2.3 ! misho 7633: ** by the SQLite core and never invoke the
1.4.2.2 misho 7634: ** sqlite3_io_methods.xFileControl method.
7635: ** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes
1.2 misho 7636: ** a pointer to the underlying [sqlite3_file] object to be written into
1.4.2.2 misho 7637: ** the space pointed to by the 4th parameter. The
7638: ** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns
7639: ** the [sqlite3_file] object associated with the journal file instead of
7640: ** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns
7641: ** a pointer to the underlying [sqlite3_vfs] object for the file.
7642: ** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter
7643: ** from the pager.
1.2 misho 7644: **
7645: ** ^If the second parameter (zDbName) does not match the name of any
7646: ** open database file, then SQLITE_ERROR is returned. ^This error
7647: ** code is not remembered and will not be recalled by [sqlite3_errcode()]
7648: ** or [sqlite3_errmsg()]. The underlying xFileControl method might
7649: ** also return SQLITE_ERROR. There is no way to distinguish between
7650: ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
7651: ** xFileControl method.
7652: **
1.4.2.2 misho 7653: ** See also: [file control opcodes]
1.2 misho 7654: */
7655: SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
7656:
7657: /*
7658: ** CAPI3REF: Testing Interface
7659: **
7660: ** ^The sqlite3_test_control() interface is used to read out internal
7661: ** state of SQLite and to inject faults into SQLite for testing
7662: ** purposes. ^The first parameter is an operation code that determines
7663: ** the number, meaning, and operation of all subsequent parameters.
7664: **
7665: ** This interface is not for use by applications. It exists solely
7666: ** for verifying the correct operation of the SQLite library. Depending
7667: ** on how the SQLite library is compiled, this interface might not exist.
7668: **
7669: ** The details of the operation codes, their meanings, the parameters
7670: ** they take, and what they do are all subject to change without notice.
7671: ** Unlike most of the SQLite API, this function is not guaranteed to
7672: ** operate consistently from one release to the next.
7673: */
7674: SQLITE_API int sqlite3_test_control(int op, ...);
7675:
7676: /*
7677: ** CAPI3REF: Testing Interface Operation Codes
7678: **
7679: ** These constants are the valid operation code parameters used
7680: ** as the first argument to [sqlite3_test_control()].
7681: **
7682: ** These parameters and their meanings are subject to change
7683: ** without notice. These values are for testing purposes only.
7684: ** Applications should not use any of these parameters or the
7685: ** [sqlite3_test_control()] interface.
7686: */
7687: #define SQLITE_TESTCTRL_FIRST 5
7688: #define SQLITE_TESTCTRL_PRNG_SAVE 5
7689: #define SQLITE_TESTCTRL_PRNG_RESTORE 6
1.4.2.3 ! misho 7690: #define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */
1.2 misho 7691: #define SQLITE_TESTCTRL_BITVEC_TEST 8
7692: #define SQLITE_TESTCTRL_FAULT_INSTALL 9
7693: #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
7694: #define SQLITE_TESTCTRL_PENDING_BYTE 11
7695: #define SQLITE_TESTCTRL_ASSERT 12
7696: #define SQLITE_TESTCTRL_ALWAYS 13
1.4.2.3 ! misho 7697: #define SQLITE_TESTCTRL_RESERVE 14 /* NOT USED */
1.2 misho 7698: #define SQLITE_TESTCTRL_OPTIMIZATIONS 15
1.4.2.2 misho 7699: #define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */
7700: #define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */
7701: #define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17
1.2 misho 7702: #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18
1.4 misho 7703: #define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */
1.4.2.1 misho 7704: #define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19
1.4 misho 7705: #define SQLITE_TESTCTRL_NEVER_CORRUPT 20
7706: #define SQLITE_TESTCTRL_VDBE_COVERAGE 21
7707: #define SQLITE_TESTCTRL_BYTEORDER 22
7708: #define SQLITE_TESTCTRL_ISINIT 23
7709: #define SQLITE_TESTCTRL_SORTER_MMAP 24
7710: #define SQLITE_TESTCTRL_IMPOSTER 25
1.4.2.2 misho 7711: #define SQLITE_TESTCTRL_PARSER_COVERAGE 26
7712: #define SQLITE_TESTCTRL_RESULT_INTREAL 27
1.4.2.3 ! misho 7713: #define SQLITE_TESTCTRL_PRNG_SEED 28
! 7714: #define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS 29
! 7715: #define SQLITE_TESTCTRL_LAST 29 /* Largest TESTCTRL */
1.4.2.2 misho 7716:
7717: /*
7718: ** CAPI3REF: SQL Keyword Checking
7719: **
1.4.2.3 ! misho 7720: ** These routines provide access to the set of SQL language keywords
1.4.2.2 misho 7721: ** recognized by SQLite. Applications can uses these routines to determine
7722: ** whether or not a specific identifier needs to be escaped (for example,
7723: ** by enclosing in double-quotes) so as not to confuse the parser.
7724: **
7725: ** The sqlite3_keyword_count() interface returns the number of distinct
7726: ** keywords understood by SQLite.
7727: **
7728: ** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and
7729: ** makes *Z point to that keyword expressed as UTF8 and writes the number
7730: ** of bytes in the keyword into *L. The string that *Z points to is not
7731: ** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns
7732: ** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z
7733: ** or L are NULL or invalid pointers then calls to
7734: ** sqlite3_keyword_name(N,Z,L) result in undefined behavior.
7735: **
7736: ** The sqlite3_keyword_check(Z,L) interface checks to see whether or not
7737: ** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero
7738: ** if it is and zero if not.
7739: **
7740: ** The parser used by SQLite is forgiving. It is often possible to use
7741: ** a keyword as an identifier as long as such use does not result in a
7742: ** parsing ambiguity. For example, the statement
7743: ** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and
7744: ** creates a new table named "BEGIN" with three columns named
7745: ** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid
7746: ** using keywords as identifiers. Common techniques used to avoid keyword
7747: ** name collisions include:
7748: ** <ul>
7749: ** <li> Put all identifier names inside double-quotes. This is the official
7750: ** SQL way to escape identifier names.
7751: ** <li> Put identifier names inside [...]. This is not standard SQL,
7752: ** but it is what SQL Server does and so lots of programmers use this
7753: ** technique.
7754: ** <li> Begin every identifier with the letter "Z" as no SQL keywords start
7755: ** with "Z".
7756: ** <li> Include a digit somewhere in every identifier name.
7757: ** </ul>
7758: **
7759: ** Note that the number of keywords understood by SQLite can depend on
7760: ** compile-time options. For example, "VACUUM" is not a keyword if
7761: ** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also,
7762: ** new keywords may be added to future releases of SQLite.
7763: */
7764: SQLITE_API int sqlite3_keyword_count(void);
7765: SQLITE_API int sqlite3_keyword_name(int,const char**,int*);
7766: SQLITE_API int sqlite3_keyword_check(const char*,int);
7767:
7768: /*
7769: ** CAPI3REF: Dynamic String Object
7770: ** KEYWORDS: {dynamic string}
7771: **
7772: ** An instance of the sqlite3_str object contains a dynamically-sized
7773: ** string under construction.
7774: **
7775: ** The lifecycle of an sqlite3_str object is as follows:
7776: ** <ol>
7777: ** <li> ^The sqlite3_str object is created using [sqlite3_str_new()].
7778: ** <li> ^Text is appended to the sqlite3_str object using various
7779: ** methods, such as [sqlite3_str_appendf()].
7780: ** <li> ^The sqlite3_str object is destroyed and the string it created
7781: ** is returned using the [sqlite3_str_finish()] interface.
7782: ** </ol>
7783: */
7784: typedef struct sqlite3_str sqlite3_str;
7785:
7786: /*
7787: ** CAPI3REF: Create A New Dynamic String Object
7788: ** CONSTRUCTOR: sqlite3_str
7789: **
7790: ** ^The [sqlite3_str_new(D)] interface allocates and initializes
7791: ** a new [sqlite3_str] object. To avoid memory leaks, the object returned by
1.4.2.3 ! misho 7792: ** [sqlite3_str_new()] must be freed by a subsequent call to
1.4.2.2 misho 7793: ** [sqlite3_str_finish(X)].
7794: **
7795: ** ^The [sqlite3_str_new(D)] interface always returns a pointer to a
7796: ** valid [sqlite3_str] object, though in the event of an out-of-memory
7797: ** error the returned object might be a special singleton that will
1.4.2.3 ! misho 7798: ** silently reject new text, always return SQLITE_NOMEM from
! 7799: ** [sqlite3_str_errcode()], always return 0 for
1.4.2.2 misho 7800: ** [sqlite3_str_length()], and always return NULL from
7801: ** [sqlite3_str_finish(X)]. It is always safe to use the value
7802: ** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter
7803: ** to any of the other [sqlite3_str] methods.
7804: **
7805: ** The D parameter to [sqlite3_str_new(D)] may be NULL. If the
7806: ** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum
7807: ** length of the string contained in the [sqlite3_str] object will be
7808: ** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead
7809: ** of [SQLITE_MAX_LENGTH].
7810: */
7811: SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*);
7812:
7813: /*
7814: ** CAPI3REF: Finalize A Dynamic String
7815: ** DESTRUCTOR: sqlite3_str
7816: **
7817: ** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X
7818: ** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()]
7819: ** that contains the constructed string. The calling application should
7820: ** pass the returned value to [sqlite3_free()] to avoid a memory leak.
7821: ** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any
7822: ** errors were encountered during construction of the string. ^The
7823: ** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the
7824: ** string in [sqlite3_str] object X is zero bytes long.
7825: */
7826: SQLITE_API char *sqlite3_str_finish(sqlite3_str*);
7827:
7828: /*
7829: ** CAPI3REF: Add Content To A Dynamic String
7830: ** METHOD: sqlite3_str
7831: **
7832: ** These interfaces add content to an sqlite3_str object previously obtained
7833: ** from [sqlite3_str_new()].
7834: **
1.4.2.3 ! misho 7835: ** ^The [sqlite3_str_appendf(X,F,...)] and
1.4.2.2 misho 7836: ** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf]
1.4.2.3 ! misho 7837: ** functionality of SQLite to append formatted text onto the end of
1.4.2.2 misho 7838: ** [sqlite3_str] object X.
7839: **
7840: ** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S
7841: ** onto the end of the [sqlite3_str] object X. N must be non-negative.
7842: ** S must contain at least N non-zero bytes of content. To append a
7843: ** zero-terminated string in its entirety, use the [sqlite3_str_appendall()]
7844: ** method instead.
7845: **
7846: ** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of
7847: ** zero-terminated string S onto the end of [sqlite3_str] object X.
7848: **
7849: ** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the
7850: ** single-byte character C onto the end of [sqlite3_str] object X.
7851: ** ^This method can be used, for example, to add whitespace indentation.
7852: **
7853: ** ^The [sqlite3_str_reset(X)] method resets the string under construction
1.4.2.3 ! misho 7854: ** inside [sqlite3_str] object X back to zero bytes in length.
1.4.2.2 misho 7855: **
7856: ** These methods do not return a result code. ^If an error occurs, that fact
7857: ** is recorded in the [sqlite3_str] object and can be recovered by a
7858: ** subsequent call to [sqlite3_str_errcode(X)].
7859: */
7860: SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...);
7861: SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list);
7862: SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N);
7863: SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn);
7864: SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C);
7865: SQLITE_API void sqlite3_str_reset(sqlite3_str*);
7866:
7867: /*
7868: ** CAPI3REF: Status Of A Dynamic String
7869: ** METHOD: sqlite3_str
7870: **
7871: ** These interfaces return the current status of an [sqlite3_str] object.
7872: **
7873: ** ^If any prior errors have occurred while constructing the dynamic string
7874: ** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return
7875: ** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns
7876: ** [SQLITE_NOMEM] following any out-of-memory error, or
7877: ** [SQLITE_TOOBIG] if the size of the dynamic string exceeds
7878: ** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors.
7879: **
7880: ** ^The [sqlite3_str_length(X)] method returns the current length, in bytes,
7881: ** of the dynamic string under construction in [sqlite3_str] object X.
7882: ** ^The length returned by [sqlite3_str_length(X)] does not include the
7883: ** zero-termination byte.
7884: **
7885: ** ^The [sqlite3_str_value(X)] method returns a pointer to the current
7886: ** content of the dynamic string under construction in X. The value
7887: ** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X
7888: ** and might be freed or altered by any subsequent method on the same
7889: ** [sqlite3_str] object. Applications must not used the pointer returned
7890: ** [sqlite3_str_value(X)] after any subsequent method call on the same
7891: ** object. ^Applications may change the content of the string returned
7892: ** by [sqlite3_str_value(X)] as long as they do not write into any bytes
7893: ** outside the range of 0 to [sqlite3_str_length(X)] and do not read or
7894: ** write any byte after any subsequent sqlite3_str method call.
7895: */
7896: SQLITE_API int sqlite3_str_errcode(sqlite3_str*);
7897: SQLITE_API int sqlite3_str_length(sqlite3_str*);
7898: SQLITE_API char *sqlite3_str_value(sqlite3_str*);
1.2 misho 7899:
7900: /*
7901: ** CAPI3REF: SQLite Runtime Status
7902: **
1.4 misho 7903: ** ^These interfaces are used to retrieve runtime status information
1.2 misho 7904: ** about the performance of SQLite, and optionally to reset various
7905: ** highwater marks. ^The first argument is an integer code for
7906: ** the specific parameter to measure. ^(Recognized integer codes
7907: ** are of the form [status parameters | SQLITE_STATUS_...].)^
7908: ** ^The current value of the parameter is returned into *pCurrent.
7909: ** ^The highest recorded value is returned in *pHighwater. ^If the
7910: ** resetFlag is true, then the highest record value is reset after
7911: ** *pHighwater is written. ^(Some parameters do not record the highest
7912: ** value. For those parameters
7913: ** nothing is written into *pHighwater and the resetFlag is ignored.)^
7914: ** ^(Other parameters record only the highwater mark and not the current
7915: ** value. For these latter parameters nothing is written into *pCurrent.)^
7916: **
1.4 misho 7917: ** ^The sqlite3_status() and sqlite3_status64() routines return
7918: ** SQLITE_OK on success and a non-zero [error code] on failure.
1.2 misho 7919: **
1.4 misho 7920: ** If either the current value or the highwater mark is too large to
7921: ** be represented by a 32-bit integer, then the values returned by
7922: ** sqlite3_status() are undefined.
1.2 misho 7923: **
7924: ** See also: [sqlite3_db_status()]
7925: */
7926: SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
1.4 misho 7927: SQLITE_API int sqlite3_status64(
7928: int op,
7929: sqlite3_int64 *pCurrent,
7930: sqlite3_int64 *pHighwater,
7931: int resetFlag
7932: );
1.2 misho 7933:
7934:
7935: /*
7936: ** CAPI3REF: Status Parameters
7937: ** KEYWORDS: {status parameters}
7938: **
7939: ** These integer constants designate various run-time status parameters
7940: ** that can be returned by [sqlite3_status()].
7941: **
7942: ** <dl>
7943: ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
7944: ** <dd>This parameter is the current amount of memory checked out
7945: ** using [sqlite3_malloc()], either directly or indirectly. The
7946: ** figure includes calls made to [sqlite3_malloc()] by the application
1.4.2.2 misho 7947: ** and internal memory usage by the SQLite library. Auxiliary page-cache
1.2 misho 7948: ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
7949: ** this parameter. The amount returned is the sum of the allocation
7950: ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
7951: **
7952: ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
7953: ** <dd>This parameter records the largest memory allocation request
7954: ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
7955: ** internal equivalents). Only the value returned in the
1.4.2.3 ! misho 7956: ** *pHighwater parameter to [sqlite3_status()] is of interest.
1.2 misho 7957: ** The value written into the *pCurrent parameter is undefined.</dd>)^
7958: **
7959: ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
7960: ** <dd>This parameter records the number of separate memory allocations
7961: ** currently checked out.</dd>)^
7962: **
7963: ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
7964: ** <dd>This parameter returns the number of pages used out of the
1.4.2.3 ! misho 7965: ** [pagecache memory allocator] that was configured using
1.2 misho 7966: ** [SQLITE_CONFIG_PAGECACHE]. The
7967: ** value returned is in pages, not in bytes.</dd>)^
7968: **
1.4.2.3 ! misho 7969: ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
1.2 misho 7970: ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
7971: ** <dd>This parameter returns the number of bytes of page cache
7972: ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
7973: ** buffer and where forced to overflow to [sqlite3_malloc()]. The
7974: ** returned value includes allocations that overflowed because they
7975: ** where too large (they were larger than the "sz" parameter to
7976: ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
7977: ** no space was left in the page cache.</dd>)^
7978: **
7979: ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
7980: ** <dd>This parameter records the largest memory allocation request
1.4.2.3 ! misho 7981: ** handed to the [pagecache memory allocator]. Only the value returned in the
! 7982: ** *pHighwater parameter to [sqlite3_status()] is of interest.
1.2 misho 7983: ** The value written into the *pCurrent parameter is undefined.</dd>)^
7984: **
1.4.2.2 misho 7985: ** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt>
7986: ** <dd>No longer used.</dd>
1.2 misho 7987: **
7988: ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
1.4.2.2 misho 7989: ** <dd>No longer used.</dd>
1.2 misho 7990: **
1.4.2.2 misho 7991: ** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
7992: ** <dd>No longer used.</dd>
1.2 misho 7993: **
7994: ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
1.4.2.3 ! misho 7995: ** <dd>The *pHighwater parameter records the deepest parser stack.
1.4 misho 7996: ** The *pCurrent value is undefined. The *pHighwater value is only
1.2 misho 7997: ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
7998: ** </dl>
7999: **
8000: ** New status parameters may be added from time to time.
8001: */
8002: #define SQLITE_STATUS_MEMORY_USED 0
8003: #define SQLITE_STATUS_PAGECACHE_USED 1
8004: #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
1.4.2.2 misho 8005: #define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */
8006: #define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */
1.2 misho 8007: #define SQLITE_STATUS_MALLOC_SIZE 5
8008: #define SQLITE_STATUS_PARSER_STACK 6
8009: #define SQLITE_STATUS_PAGECACHE_SIZE 7
1.4.2.2 misho 8010: #define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */
1.2 misho 8011: #define SQLITE_STATUS_MALLOC_COUNT 9
8012:
8013: /*
8014: ** CAPI3REF: Database Connection Status
1.4 misho 8015: ** METHOD: sqlite3
1.2 misho 8016: **
1.4.2.3 ! misho 8017: ** ^This interface is used to retrieve runtime status information
1.2 misho 8018: ** about a single [database connection]. ^The first argument is the
8019: ** database connection object to be interrogated. ^The second argument
8020: ** is an integer constant, taken from the set of
8021: ** [SQLITE_DBSTATUS options], that
1.4.2.3 ! misho 8022: ** determines the parameter to interrogate. The set of
1.2 misho 8023: ** [SQLITE_DBSTATUS options] is likely
8024: ** to grow in future releases of SQLite.
8025: **
8026: ** ^The current value of the requested parameter is written into *pCur
8027: ** and the highest instantaneous value is written into *pHiwtr. ^If
8028: ** the resetFlg is true, then the highest instantaneous value is
8029: ** reset back down to the current value.
8030: **
8031: ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
8032: ** non-zero [error code] on failure.
8033: **
8034: ** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
8035: */
8036: SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
8037:
8038: /*
8039: ** CAPI3REF: Status Parameters for database connections
8040: ** KEYWORDS: {SQLITE_DBSTATUS options}
8041: **
8042: ** These constants are the available integer "verbs" that can be passed as
8043: ** the second argument to the [sqlite3_db_status()] interface.
8044: **
8045: ** New verbs may be added in future releases of SQLite. Existing verbs
8046: ** might be discontinued. Applications should check the return code from
8047: ** [sqlite3_db_status()] to make sure that the call worked.
8048: ** The [sqlite3_db_status()] interface will return a non-zero error code
8049: ** if a discontinued or unsupported verb is invoked.
8050: **
8051: ** <dl>
8052: ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
8053: ** <dd>This parameter returns the number of lookaside memory slots currently
8054: ** checked out.</dd>)^
8055: **
8056: ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
1.4.2.3 ! misho 8057: ** <dd>This parameter returns the number of malloc attempts that were
1.2 misho 8058: ** satisfied using lookaside memory. Only the high-water value is meaningful;
8059: ** the current value is always zero.)^
8060: **
8061: ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
8062: ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
8063: ** <dd>This parameter returns the number malloc attempts that might have
8064: ** been satisfied using lookaside memory but failed due to the amount of
8065: ** memory requested being larger than the lookaside slot size.
8066: ** Only the high-water value is meaningful;
8067: ** the current value is always zero.)^
8068: **
8069: ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
8070: ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
8071: ** <dd>This parameter returns the number malloc attempts that might have
8072: ** been satisfied using lookaside memory but failed due to all lookaside
8073: ** memory already being in use.
8074: ** Only the high-water value is meaningful;
8075: ** the current value is always zero.)^
8076: **
8077: ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
1.4 misho 8078: ** <dd>This parameter returns the approximate number of bytes of heap
1.2 misho 8079: ** memory used by all pager caches associated with the database connection.)^
8080: ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
8081: **
1.4.2.3 ! misho 8082: ** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]]
1.4 misho 8083: ** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt>
8084: ** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a
8085: ** pager cache is shared between two or more connections the bytes of heap
8086: ** memory used by that pager cache is divided evenly between the attached
8087: ** connections.)^ In other words, if none of the pager caches associated
8088: ** with the database connection are shared, this request returns the same
8089: ** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are
8090: ** shared, the value returned by this call will be smaller than that returned
8091: ** by DBSTATUS_CACHE_USED. ^The highwater mark associated with
8092: ** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.
8093: **
1.2 misho 8094: ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
1.4 misho 8095: ** <dd>This parameter returns the approximate number of bytes of heap
1.2 misho 8096: ** memory used to store the schema for all databases associated
1.4.2.3 ! misho 8097: ** with the connection - main, temp, and any [ATTACH]-ed databases.)^
1.2 misho 8098: ** ^The full amount of memory used by the schemas is reported, even if the
8099: ** schema memory is shared with other database connections due to
8100: ** [shared cache mode] being enabled.
8101: ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
8102: **
8103: ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
1.4 misho 8104: ** <dd>This parameter returns the approximate number of bytes of heap
1.2 misho 8105: ** and lookaside memory used by all prepared statements associated with
8106: ** the database connection.)^
8107: ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
8108: ** </dd>
8109: **
8110: ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
8111: ** <dd>This parameter returns the number of pager cache hits that have
1.4.2.3 ! misho 8112: ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
1.2 misho 8113: ** is always 0.
8114: ** </dd>
8115: **
8116: ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
8117: ** <dd>This parameter returns the number of pager cache misses that have
1.4.2.3 ! misho 8118: ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
1.2 misho 8119: ** is always 0.
8120: ** </dd>
1.3 misho 8121: **
8122: ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>
8123: ** <dd>This parameter returns the number of dirty cache entries that have
8124: ** been written to disk. Specifically, the number of pages written to the
8125: ** wal file in wal mode databases, or the number of pages written to the
8126: ** database file in rollback mode databases. Any pages written as part of
8127: ** transaction rollback or database recovery operations are not included.
8128: ** If an IO or other error occurs while writing a page to disk, the effect
8129: ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
8130: ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
8131: ** </dd>
1.4 misho 8132: **
1.4.2.2 misho 8133: ** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt>
8134: ** <dd>This parameter returns the number of dirty cache entries that have
8135: ** been written to disk in the middle of a transaction due to the page
8136: ** cache overflowing. Transactions are more efficient if they are written
8137: ** to disk all at once. When pages spill mid-transaction, that introduces
8138: ** additional overhead. This parameter can be used help identify
1.4.2.3 ! misho 8139: ** inefficiencies that can be resolved by increasing the cache size.
1.4.2.2 misho 8140: ** </dd>
8141: **
1.4 misho 8142: ** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
8143: ** <dd>This parameter returns zero for the current value if and only if
8144: ** all foreign key constraints (deferred or immediate) have been
8145: ** resolved.)^ ^The highwater mark is always 0.
8146: ** </dd>
1.2 misho 8147: ** </dl>
8148: */
8149: #define SQLITE_DBSTATUS_LOOKASIDE_USED 0
8150: #define SQLITE_DBSTATUS_CACHE_USED 1
8151: #define SQLITE_DBSTATUS_SCHEMA_USED 2
8152: #define SQLITE_DBSTATUS_STMT_USED 3
8153: #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4
8154: #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5
8155: #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6
8156: #define SQLITE_DBSTATUS_CACHE_HIT 7
8157: #define SQLITE_DBSTATUS_CACHE_MISS 8
1.3 misho 8158: #define SQLITE_DBSTATUS_CACHE_WRITE 9
1.4 misho 8159: #define SQLITE_DBSTATUS_DEFERRED_FKS 10
8160: #define SQLITE_DBSTATUS_CACHE_USED_SHARED 11
1.4.2.2 misho 8161: #define SQLITE_DBSTATUS_CACHE_SPILL 12
8162: #define SQLITE_DBSTATUS_MAX 12 /* Largest defined DBSTATUS */
1.2 misho 8163:
8164:
8165: /*
8166: ** CAPI3REF: Prepared Statement Status
1.4 misho 8167: ** METHOD: sqlite3_stmt
1.2 misho 8168: **
8169: ** ^(Each prepared statement maintains various
8170: ** [SQLITE_STMTSTATUS counters] that measure the number
8171: ** of times it has performed specific operations.)^ These counters can
8172: ** be used to monitor the performance characteristics of the prepared
8173: ** statements. For example, if the number of table steps greatly exceeds
8174: ** the number of table searches or result rows, that would tend to indicate
8175: ** that the prepared statement is using a full table scan rather than
1.4.2.3 ! misho 8176: ** an index.
1.2 misho 8177: **
8178: ** ^(This interface is used to retrieve and reset counter values from
8179: ** a [prepared statement]. The first argument is the prepared statement
8180: ** object to be interrogated. The second argument
8181: ** is an integer code for a specific [SQLITE_STMTSTATUS counter]
8182: ** to be interrogated.)^
8183: ** ^The current value of the requested counter is returned.
8184: ** ^If the resetFlg is true, then the counter is reset to zero after this
8185: ** interface call returns.
8186: **
8187: ** See also: [sqlite3_status()] and [sqlite3_db_status()].
8188: */
8189: SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
8190:
8191: /*
8192: ** CAPI3REF: Status Parameters for prepared statements
8193: ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
8194: **
8195: ** These preprocessor macros define integer codes that name counter
8196: ** values associated with the [sqlite3_stmt_status()] interface.
8197: ** The meanings of the various counters are as follows:
8198: **
8199: ** <dl>
8200: ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
8201: ** <dd>^This is the number of times that SQLite has stepped forward in
8202: ** a table as part of a full table scan. Large numbers for this counter
1.4.2.3 ! misho 8203: ** may indicate opportunities for performance improvement through
1.2 misho 8204: ** careful use of indices.</dd>
8205: **
8206: ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
8207: ** <dd>^This is the number of sort operations that have occurred.
8208: ** A non-zero value in this counter may indicate an opportunity to
8209: ** improvement performance through careful use of indices.</dd>
8210: **
8211: ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
8212: ** <dd>^This is the number of rows inserted into transient indices that
8213: ** were created automatically in order to help joins run faster.
8214: ** A non-zero value in this counter may indicate an opportunity to
8215: ** improvement performance by adding permanent indices that do not
8216: ** need to be reinitialized each time the statement is run.</dd>
1.4 misho 8217: **
8218: ** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
8219: ** <dd>^This is the number of virtual machine operations executed
8220: ** by the prepared statement if that number is less than or equal
1.4.2.3 ! misho 8221: ** to 2147483647. The number of virtual machine operations can be
1.4 misho 8222: ** used as a proxy for the total work done by the prepared statement.
8223: ** If the number of virtual machine operations exceeds 2147483647
8224: ** then the value returned by this statement status code is undefined.
1.4.2.2 misho 8225: **
8226: ** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt>
8227: ** <dd>^This is the number of times that the prepare statement has been
1.4.2.3 ! misho 8228: ** automatically regenerated due to schema changes or changes to
1.4.2.2 misho 8229: ** [bound parameters] that might affect the query plan.
8230: **
8231: ** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt>
8232: ** <dd>^This is the number of times that the prepared statement has
8233: ** been run. A single "run" for the purposes of this counter is one
8234: ** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()].
8235: ** The counter is incremented on the first [sqlite3_step()] call of each
8236: ** cycle.
8237: **
8238: ** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt>
8239: ** <dd>^This is the approximate number of bytes of heap memory
8240: ** used to store the prepared statement. ^This value is not actually
8241: ** a counter, and so the resetFlg parameter to sqlite3_stmt_status()
8242: ** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED.
1.4 misho 8243: ** </dd>
1.2 misho 8244: ** </dl>
8245: */
8246: #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
8247: #define SQLITE_STMTSTATUS_SORT 2
8248: #define SQLITE_STMTSTATUS_AUTOINDEX 3
1.4 misho 8249: #define SQLITE_STMTSTATUS_VM_STEP 4
1.4.2.2 misho 8250: #define SQLITE_STMTSTATUS_REPREPARE 5
8251: #define SQLITE_STMTSTATUS_RUN 6
8252: #define SQLITE_STMTSTATUS_MEMUSED 99
1.2 misho 8253:
8254: /*
8255: ** CAPI3REF: Custom Page Cache Object
8256: **
8257: ** The sqlite3_pcache type is opaque. It is implemented by
8258: ** the pluggable module. The SQLite core has no knowledge of
8259: ** its size or internal structure and never deals with the
8260: ** sqlite3_pcache object except by holding and passing pointers
8261: ** to the object.
8262: **
8263: ** See [sqlite3_pcache_methods2] for additional information.
8264: */
8265: typedef struct sqlite3_pcache sqlite3_pcache;
8266:
8267: /*
8268: ** CAPI3REF: Custom Page Cache Object
8269: **
8270: ** The sqlite3_pcache_page object represents a single page in the
8271: ** page cache. The page cache will allocate instances of this
8272: ** object. Various methods of the page cache use pointers to instances
8273: ** of this object as parameters or as their return value.
8274: **
8275: ** See [sqlite3_pcache_methods2] for additional information.
8276: */
8277: typedef struct sqlite3_pcache_page sqlite3_pcache_page;
8278: struct sqlite3_pcache_page {
8279: void *pBuf; /* The content of the page */
8280: void *pExtra; /* Extra information associated with the page */
8281: };
8282:
8283: /*
8284: ** CAPI3REF: Application Defined Page Cache.
8285: ** KEYWORDS: {page cache}
8286: **
8287: ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
1.4.2.3 ! misho 8288: ** register an alternative page cache implementation by passing in an
1.2 misho 8289: ** instance of the sqlite3_pcache_methods2 structure.)^
1.4.2.3 ! misho 8290: ** In many applications, most of the heap memory allocated by
1.2 misho 8291: ** SQLite is used for the page cache.
1.4.2.3 ! misho 8292: ** By implementing a
1.2 misho 8293: ** custom page cache using this API, an application can better control
1.4.2.3 ! misho 8294: ** the amount of memory consumed by SQLite, the way in which
! 8295: ** that memory is allocated and released, and the policies used to
! 8296: ** determine exactly which parts of a database file are cached and for
1.2 misho 8297: ** how long.
8298: **
8299: ** The alternative page cache mechanism is an
8300: ** extreme measure that is only needed by the most demanding applications.
8301: ** The built-in page cache is recommended for most uses.
8302: **
8303: ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
8304: ** internal buffer by SQLite within the call to [sqlite3_config]. Hence
8305: ** the application may discard the parameter after the call to
8306: ** [sqlite3_config()] returns.)^
8307: **
8308: ** [[the xInit() page cache method]]
1.4.2.3 ! misho 8309: ** ^(The xInit() method is called once for each effective
1.2 misho 8310: ** call to [sqlite3_initialize()])^
8311: ** (usually only once during the lifetime of the process). ^(The xInit()
8312: ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
1.4.2.3 ! misho 8313: ** The intent of the xInit() method is to set up global data structures
! 8314: ** required by the custom page cache implementation.
! 8315: ** ^(If the xInit() method is NULL, then the
1.2 misho 8316: ** built-in default page cache is used instead of the application defined
8317: ** page cache.)^
8318: **
8319: ** [[the xShutdown() page cache method]]
8320: ** ^The xShutdown() method is called by [sqlite3_shutdown()].
1.4.2.3 ! misho 8321: ** It can be used to clean up
1.2 misho 8322: ** any outstanding resources before process shutdown, if required.
8323: ** ^The xShutdown() method may be NULL.
8324: **
8325: ** ^SQLite automatically serializes calls to the xInit method,
8326: ** so the xInit method need not be threadsafe. ^The
8327: ** xShutdown method is only called from [sqlite3_shutdown()] so it does
8328: ** not need to be threadsafe either. All other methods must be threadsafe
8329: ** in multithreaded applications.
8330: **
8331: ** ^SQLite will never invoke xInit() more than once without an intervening
8332: ** call to xShutdown().
8333: **
8334: ** [[the xCreate() page cache methods]]
8335: ** ^SQLite invokes the xCreate() method to construct a new cache instance.
8336: ** SQLite will typically create one cache instance for each open database file,
8337: ** though this is not guaranteed. ^The
8338: ** first parameter, szPage, is the size in bytes of the pages that must
8339: ** be allocated by the cache. ^szPage will always a power of two. ^The
1.4.2.3 ! misho 8340: ** second parameter szExtra is a number of bytes of extra storage
1.2 misho 8341: ** associated with each page cache entry. ^The szExtra parameter will
8342: ** a number less than 250. SQLite will use the
8343: ** extra szExtra bytes on each page to store metadata about the underlying
8344: ** database page on disk. The value passed into szExtra depends
8345: ** on the SQLite version, the target platform, and how SQLite was compiled.
8346: ** ^The third argument to xCreate(), bPurgeable, is true if the cache being
8347: ** created will be used to cache database pages of a file stored on disk, or
8348: ** false if it is used for an in-memory database. The cache implementation
8349: ** does not have to do anything special based with the value of bPurgeable;
8350: ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
8351: ** never invoke xUnpin() except to deliberately delete a page.
8352: ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
1.4.2.3 ! misho 8353: ** false will always have the "discard" flag set to true.
1.2 misho 8354: ** ^Hence, a cache created with bPurgeable false will
8355: ** never contain any unpinned pages.
8356: **
8357: ** [[the xCachesize() page cache method]]
8358: ** ^(The xCachesize() method may be called at any time by SQLite to set the
8359: ** suggested maximum cache-size (number of pages stored by) the cache
8360: ** instance passed as the first argument. This is the value configured using
8361: ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable
8362: ** parameter, the implementation is not required to do anything with this
8363: ** value; it is advisory only.
8364: **
8365: ** [[the xPagecount() page cache methods]]
8366: ** The xPagecount() method must return the number of pages currently
8367: ** stored in the cache, both pinned and unpinned.
1.4.2.3 ! misho 8368: **
1.2 misho 8369: ** [[the xFetch() page cache methods]]
1.4.2.3 ! misho 8370: ** The xFetch() method locates a page in the cache and returns a pointer to
1.2 misho 8371: ** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
8372: ** The pBuf element of the returned sqlite3_pcache_page object will be a
1.4.2.3 ! misho 8373: ** pointer to a buffer of szPage bytes used to store the content of a
1.2 misho 8374: ** single database page. The pExtra element of sqlite3_pcache_page will be
8375: ** a pointer to the szExtra bytes of extra storage that SQLite has requested
8376: ** for each entry in the page cache.
8377: **
8378: ** The page to be fetched is determined by the key. ^The minimum key value
8379: ** is 1. After it has been retrieved using xFetch, the page is considered
8380: ** to be "pinned".
8381: **
8382: ** If the requested page is already in the page cache, then the page cache
8383: ** implementation must return a pointer to the page buffer with its content
8384: ** intact. If the requested page is not already in the cache, then the
8385: ** cache implementation should use the value of the createFlag
8386: ** parameter to help it determined what action to take:
8387: **
8388: ** <table border=1 width=85% align=center>
1.4 misho 8389: ** <tr><th> createFlag <th> Behavior when page is not already in cache
1.2 misho 8390: ** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
8391: ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
8392: ** Otherwise return NULL.
8393: ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
8394: ** NULL if allocating a new page is effectively impossible.
8395: ** </table>
8396: **
8397: ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite
8398: ** will only use a createFlag of 2 after a prior call with a createFlag of 1
1.4.2.3 ! misho 8399: ** failed.)^ In between the xFetch() calls, SQLite may
1.2 misho 8400: ** attempt to unpin one or more cache pages by spilling the content of
8401: ** pinned pages to disk and synching the operating system disk cache.
8402: **
8403: ** [[the xUnpin() page cache method]]
8404: ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
8405: ** as its second argument. If the third parameter, discard, is non-zero,
8406: ** then the page must be evicted from the cache.
8407: ** ^If the discard parameter is
8408: ** zero, then the page may be discarded or retained at the discretion of
8409: ** page cache implementation. ^The page cache implementation
8410: ** may choose to evict unpinned pages at any time.
8411: **
1.4.2.3 ! misho 8412: ** The cache must not perform any reference counting. A single
! 8413: ** call to xUnpin() unpins the page regardless of the number of prior calls
1.2 misho 8414: ** to xFetch().
8415: **
8416: ** [[the xRekey() page cache methods]]
8417: ** The xRekey() method is used to change the key value associated with the
8418: ** page passed as the second argument. If the cache
8419: ** previously contains an entry associated with newKey, it must be
8420: ** discarded. ^Any prior cache entry associated with newKey is guaranteed not
8421: ** to be pinned.
8422: **
8423: ** When SQLite calls the xTruncate() method, the cache must discard all
8424: ** existing cache entries with page numbers (keys) greater than or equal
8425: ** to the value of the iLimit parameter passed to xTruncate(). If any
8426: ** of these pages are pinned, they are implicitly unpinned, meaning that
8427: ** they can be safely discarded.
8428: **
8429: ** [[the xDestroy() page cache method]]
8430: ** ^The xDestroy() method is used to delete a cache allocated by xCreate().
8431: ** All resources associated with the specified cache should be freed. ^After
8432: ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
8433: ** handle invalid, and will not use it with any other sqlite3_pcache_methods2
8434: ** functions.
8435: **
8436: ** [[the xShrink() page cache method]]
8437: ** ^SQLite invokes the xShrink() method when it wants the page cache to
8438: ** free up as much of heap memory as possible. The page cache implementation
8439: ** is not obligated to free any memory, but well-behaved implementations should
8440: ** do their best.
8441: */
8442: typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
8443: struct sqlite3_pcache_methods2 {
8444: int iVersion;
8445: void *pArg;
8446: int (*xInit)(void*);
8447: void (*xShutdown)(void*);
8448: sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
8449: void (*xCachesize)(sqlite3_pcache*, int nCachesize);
8450: int (*xPagecount)(sqlite3_pcache*);
8451: sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
8452: void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
1.4.2.3 ! misho 8453: void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
1.2 misho 8454: unsigned oldKey, unsigned newKey);
8455: void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
8456: void (*xDestroy)(sqlite3_pcache*);
8457: void (*xShrink)(sqlite3_pcache*);
8458: };
8459:
8460: /*
8461: ** This is the obsolete pcache_methods object that has now been replaced
8462: ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is
8463: ** retained in the header file for backwards compatibility only.
8464: */
8465: typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
8466: struct sqlite3_pcache_methods {
8467: void *pArg;
8468: int (*xInit)(void*);
8469: void (*xShutdown)(void*);
8470: sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
8471: void (*xCachesize)(sqlite3_pcache*, int nCachesize);
8472: int (*xPagecount)(sqlite3_pcache*);
8473: void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
8474: void (*xUnpin)(sqlite3_pcache*, void*, int discard);
8475: void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
8476: void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
8477: void (*xDestroy)(sqlite3_pcache*);
8478: };
8479:
8480:
8481: /*
8482: ** CAPI3REF: Online Backup Object
8483: **
8484: ** The sqlite3_backup object records state information about an ongoing
8485: ** online backup operation. ^The sqlite3_backup object is created by
8486: ** a call to [sqlite3_backup_init()] and is destroyed by a call to
8487: ** [sqlite3_backup_finish()].
8488: **
8489: ** See Also: [Using the SQLite Online Backup API]
8490: */
8491: typedef struct sqlite3_backup sqlite3_backup;
8492:
8493: /*
8494: ** CAPI3REF: Online Backup API.
8495: **
8496: ** The backup API copies the content of one database into another.
8497: ** It is useful either for creating backups of databases or
1.4.2.3 ! misho 8498: ** for copying in-memory databases to or from persistent files.
1.2 misho 8499: **
8500: ** See Also: [Using the SQLite Online Backup API]
8501: **
8502: ** ^SQLite holds a write transaction open on the destination database file
8503: ** for the duration of the backup operation.
8504: ** ^The source database is read-locked only while it is being read;
8505: ** it is not locked continuously for the entire backup operation.
8506: ** ^Thus, the backup may be performed on a live source database without
8507: ** preventing other database connections from
8508: ** reading or writing to the source database while the backup is underway.
1.4.2.3 ! misho 8509: **
! 8510: ** ^(To perform a backup operation:
1.2 misho 8511: ** <ol>
8512: ** <li><b>sqlite3_backup_init()</b> is called once to initialize the
1.4.2.3 ! misho 8513: ** backup,
! 8514: ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
1.2 misho 8515: ** the data between the two databases, and finally
1.4.2.3 ! misho 8516: ** <li><b>sqlite3_backup_finish()</b> is called to release all resources
! 8517: ** associated with the backup operation.
1.2 misho 8518: ** </ol>)^
8519: ** There should be exactly one call to sqlite3_backup_finish() for each
8520: ** successful call to sqlite3_backup_init().
8521: **
8522: ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
8523: **
1.4.2.3 ! misho 8524: ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
! 8525: ** [database connection] associated with the destination database
1.2 misho 8526: ** and the database name, respectively.
8527: ** ^The database name is "main" for the main database, "temp" for the
8528: ** temporary database, or the name specified after the AS keyword in
8529: ** an [ATTACH] statement for an attached database.
1.4.2.3 ! misho 8530: ** ^The S and M arguments passed to
1.2 misho 8531: ** sqlite3_backup_init(D,N,S,M) identify the [database connection]
8532: ** and database name of the source database, respectively.
8533: ** ^The source and destination [database connections] (parameters S and D)
8534: ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
8535: ** an error.
8536: **
1.4.2.3 ! misho 8537: ** ^A call to sqlite3_backup_init() will fail, returning NULL, if
! 8538: ** there is already a read or read-write transaction open on the
1.4 misho 8539: ** destination database.
8540: **
1.2 misho 8541: ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
8542: ** returned and an error code and error message are stored in the
8543: ** destination [database connection] D.
8544: ** ^The error code and message for the failed call to sqlite3_backup_init()
8545: ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
8546: ** [sqlite3_errmsg16()] functions.
8547: ** ^A successful call to sqlite3_backup_init() returns a pointer to an
8548: ** [sqlite3_backup] object.
8549: ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
1.4.2.3 ! misho 8550: ** sqlite3_backup_finish() functions to perform the specified backup
1.2 misho 8551: ** operation.
8552: **
8553: ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
8554: **
1.4.2.3 ! misho 8555: ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
1.2 misho 8556: ** the source and destination databases specified by [sqlite3_backup] object B.
1.4.2.3 ! misho 8557: ** ^If N is negative, all remaining source pages are copied.
1.2 misho 8558: ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
8559: ** are still more pages to be copied, then the function returns [SQLITE_OK].
8560: ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
8561: ** from source to destination, then it returns [SQLITE_DONE].
8562: ** ^If an error occurs while running sqlite3_backup_step(B,N),
8563: ** then an [error code] is returned. ^As well as [SQLITE_OK] and
8564: ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
8565: ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
8566: ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
8567: **
8568: ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
8569: ** <ol>
8570: ** <li> the destination database was opened read-only, or
8571: ** <li> the destination database is using write-ahead-log journaling
8572: ** and the destination and source page sizes differ, or
8573: ** <li> the destination database is an in-memory database and the
8574: ** destination and source page sizes differ.
8575: ** </ol>)^
8576: **
8577: ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
8578: ** the [sqlite3_busy_handler | busy-handler function]
1.4.2.3 ! misho 8579: ** is invoked (if one is specified). ^If the
! 8580: ** busy-handler returns non-zero before the lock is available, then
1.2 misho 8581: ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
8582: ** sqlite3_backup_step() can be retried later. ^If the source
8583: ** [database connection]
8584: ** is being used to write to the source database when sqlite3_backup_step()
8585: ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
8586: ** case the call to sqlite3_backup_step() can be retried later on. ^(If
8587: ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
1.4.2.3 ! misho 8588: ** [SQLITE_READONLY] is returned, then
! 8589: ** there is no point in retrying the call to sqlite3_backup_step(). These
! 8590: ** errors are considered fatal.)^ The application must accept
! 8591: ** that the backup operation has failed and pass the backup operation handle
1.2 misho 8592: ** to the sqlite3_backup_finish() to release associated resources.
8593: **
8594: ** ^The first call to sqlite3_backup_step() obtains an exclusive lock
1.4.2.3 ! misho 8595: ** on the destination file. ^The exclusive lock is not released until either
! 8596: ** sqlite3_backup_finish() is called or the backup operation is complete
1.2 misho 8597: ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
8598: ** sqlite3_backup_step() obtains a [shared lock] on the source database that
8599: ** lasts for the duration of the sqlite3_backup_step() call.
8600: ** ^Because the source database is not locked between calls to
8601: ** sqlite3_backup_step(), the source database may be modified mid-way
8602: ** through the backup process. ^If the source database is modified by an
8603: ** external process or via a database connection other than the one being
8604: ** used by the backup operation, then the backup will be automatically
1.4.2.3 ! misho 8605: ** restarted by the next call to sqlite3_backup_step(). ^If the source
1.2 misho 8606: ** database is modified by the using the same database connection as is used
8607: ** by the backup operation, then the backup database is automatically
8608: ** updated at the same time.
8609: **
8610: ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
8611: **
1.4.2.3 ! misho 8612: ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
1.2 misho 8613: ** application wishes to abandon the backup operation, the application
8614: ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
8615: ** ^The sqlite3_backup_finish() interfaces releases all
1.4.2.3 ! misho 8616: ** resources associated with the [sqlite3_backup] object.
1.2 misho 8617: ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
8618: ** active write-transaction on the destination database is rolled back.
8619: ** The [sqlite3_backup] object is invalid
8620: ** and may not be used following a call to sqlite3_backup_finish().
8621: **
8622: ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
8623: ** sqlite3_backup_step() errors occurred, regardless or whether or not
8624: ** sqlite3_backup_step() completed.
8625: ** ^If an out-of-memory condition or IO error occurred during any prior
8626: ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
8627: ** sqlite3_backup_finish() returns the corresponding [error code].
8628: **
8629: ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
8630: ** is not a permanent error and does not affect the return value of
8631: ** sqlite3_backup_finish().
8632: **
1.4 misho 8633: ** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]
1.2 misho 8634: ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
8635: **
1.4 misho 8636: ** ^The sqlite3_backup_remaining() routine returns the number of pages still
8637: ** to be backed up at the conclusion of the most recent sqlite3_backup_step().
8638: ** ^The sqlite3_backup_pagecount() routine returns the total number of pages
8639: ** in the source database at the conclusion of the most recent
8640: ** sqlite3_backup_step().
8641: ** ^(The values returned by these functions are only updated by
8642: ** sqlite3_backup_step(). If the source database is modified in a way that
8643: ** changes the size of the source database or the number of pages remaining,
8644: ** those changes are not reflected in the output of sqlite3_backup_pagecount()
8645: ** and sqlite3_backup_remaining() until after the next
8646: ** sqlite3_backup_step().)^
1.2 misho 8647: **
8648: ** <b>Concurrent Usage of Database Handles</b>
8649: **
8650: ** ^The source [database connection] may be used by the application for other
8651: ** purposes while a backup operation is underway or being initialized.
8652: ** ^If SQLite is compiled and configured to support threadsafe database
8653: ** connections, then the source database connection may be used concurrently
8654: ** from within other threads.
8655: **
1.4.2.3 ! misho 8656: ** However, the application must guarantee that the destination
! 8657: ** [database connection] is not passed to any other API (by any thread) after
1.2 misho 8658: ** sqlite3_backup_init() is called and before the corresponding call to
8659: ** sqlite3_backup_finish(). SQLite does not currently check to see
8660: ** if the application incorrectly accesses the destination [database connection]
8661: ** and so no error code is reported, but the operations may malfunction
8662: ** nevertheless. Use of the destination database connection while a
8663: ** backup is in progress might also also cause a mutex deadlock.
8664: **
8665: ** If running in [shared cache mode], the application must
8666: ** guarantee that the shared cache used by the destination database
8667: ** is not accessed while the backup is running. In practice this means
1.4.2.3 ! misho 8668: ** that the application must guarantee that the disk file being
1.2 misho 8669: ** backed up to is not accessed by any connection within the process,
8670: ** not just the specific connection that was passed to sqlite3_backup_init().
8671: **
1.4.2.3 ! misho 8672: ** The [sqlite3_backup] object itself is partially threadsafe. Multiple
1.2 misho 8673: ** threads may safely make multiple concurrent calls to sqlite3_backup_step().
8674: ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
8675: ** APIs are not strictly speaking threadsafe. If they are invoked at the
8676: ** same time as another thread is invoking sqlite3_backup_step() it is
8677: ** possible that they return invalid values.
8678: */
8679: SQLITE_API sqlite3_backup *sqlite3_backup_init(
8680: sqlite3 *pDest, /* Destination database handle */
8681: const char *zDestName, /* Destination database name */
8682: sqlite3 *pSource, /* Source database handle */
8683: const char *zSourceName /* Source database name */
8684: );
8685: SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
8686: SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
8687: SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
8688: SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
8689:
8690: /*
8691: ** CAPI3REF: Unlock Notification
1.4 misho 8692: ** METHOD: sqlite3
1.2 misho 8693: **
8694: ** ^When running in shared-cache mode, a database operation may fail with
8695: ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
8696: ** individual tables within the shared-cache cannot be obtained. See
1.4.2.3 ! misho 8697: ** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
! 8698: ** ^This API may be used to register a callback that SQLite will invoke
1.2 misho 8699: ** when the connection currently holding the required lock relinquishes it.
8700: ** ^This API is only available if the library was compiled with the
8701: ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
8702: **
8703: ** See Also: [Using the SQLite Unlock Notification Feature].
8704: **
8705: ** ^Shared-cache locks are released when a database connection concludes
1.4.2.3 ! misho 8706: ** its current transaction, either by committing it or rolling it back.
1.2 misho 8707: **
8708: ** ^When a connection (known as the blocked connection) fails to obtain a
8709: ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
8710: ** identity of the database connection (the blocking connection) that
1.4.2.3 ! misho 8711: ** has locked the required resource is stored internally. ^After an
1.2 misho 8712: ** application receives an SQLITE_LOCKED error, it may call the
1.4.2.3 ! misho 8713: ** sqlite3_unlock_notify() method with the blocked connection handle as
1.2 misho 8714: ** the first argument to register for a callback that will be invoked
8715: ** when the blocking connections current transaction is concluded. ^The
8716: ** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
1.4.2.3 ! misho 8717: ** call that concludes the blocking connection's transaction.
1.2 misho 8718: **
8719: ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
8720: ** there is a chance that the blocking connection will have already
8721: ** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
8722: ** If this happens, then the specified callback is invoked immediately,
8723: ** from within the call to sqlite3_unlock_notify().)^
8724: **
8725: ** ^If the blocked connection is attempting to obtain a write-lock on a
8726: ** shared-cache table, and more than one other connection currently holds
1.4.2.3 ! misho 8727: ** a read-lock on the same table, then SQLite arbitrarily selects one of
1.2 misho 8728: ** the other connections to use as the blocking connection.
8729: **
1.4.2.3 ! misho 8730: ** ^(There may be at most one unlock-notify callback registered by a
1.2 misho 8731: ** blocked connection. If sqlite3_unlock_notify() is called when the
8732: ** blocked connection already has a registered unlock-notify callback,
8733: ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
8734: ** called with a NULL pointer as its second argument, then any existing
1.4.2.3 ! misho 8735: ** unlock-notify callback is canceled. ^The blocked connections
1.2 misho 8736: ** unlock-notify callback may also be canceled by closing the blocked
8737: ** connection using [sqlite3_close()].
8738: **
8739: ** The unlock-notify callback is not reentrant. If an application invokes
8740: ** any sqlite3_xxx API functions from within an unlock-notify callback, a
8741: ** crash or deadlock may be the result.
8742: **
8743: ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
8744: ** returns SQLITE_OK.
8745: **
8746: ** <b>Callback Invocation Details</b>
8747: **
1.4.2.3 ! misho 8748: ** When an unlock-notify callback is registered, the application provides a
1.2 misho 8749: ** single void* pointer that is passed to the callback when it is invoked.
8750: ** However, the signature of the callback function allows SQLite to pass
8751: ** it an array of void* context pointers. The first argument passed to
8752: ** an unlock-notify callback is a pointer to an array of void* pointers,
8753: ** and the second is the number of entries in the array.
8754: **
1.4.2.3 ! misho 8755: ** When a blocking connection's transaction is concluded, there may be
1.2 misho 8756: ** more than one blocked connection that has registered for an unlock-notify
8757: ** callback. ^If two or more such blocked connections have specified the
8758: ** same callback function, then instead of invoking the callback function
8759: ** multiple times, it is invoked once with the set of void* context pointers
8760: ** specified by the blocked connections bundled together into an array.
1.4.2.3 ! misho 8761: ** This gives the application an opportunity to prioritize any actions
1.2 misho 8762: ** related to the set of unblocked database connections.
8763: **
8764: ** <b>Deadlock Detection</b>
8765: **
1.4.2.3 ! misho 8766: ** Assuming that after registering for an unlock-notify callback a
1.2 misho 8767: ** database waits for the callback to be issued before taking any further
8768: ** action (a reasonable assumption), then using this API may cause the
8769: ** application to deadlock. For example, if connection X is waiting for
8770: ** connection Y's transaction to be concluded, and similarly connection
8771: ** Y is waiting on connection X's transaction, then neither connection
8772: ** will proceed and the system may remain deadlocked indefinitely.
8773: **
8774: ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
8775: ** detection. ^If a given call to sqlite3_unlock_notify() would put the
8776: ** system in a deadlocked state, then SQLITE_LOCKED is returned and no
8777: ** unlock-notify callback is registered. The system is said to be in
8778: ** a deadlocked state if connection A has registered for an unlock-notify
8779: ** callback on the conclusion of connection B's transaction, and connection
8780: ** B has itself registered for an unlock-notify callback when connection
8781: ** A's transaction is concluded. ^Indirect deadlock is also detected, so
8782: ** the system is also considered to be deadlocked if connection B has
8783: ** registered for an unlock-notify callback on the conclusion of connection
8784: ** C's transaction, where connection C is waiting on connection A. ^Any
8785: ** number of levels of indirection are allowed.
8786: **
8787: ** <b>The "DROP TABLE" Exception</b>
8788: **
1.4.2.3 ! misho 8789: ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
1.2 misho 8790: ** always appropriate to call sqlite3_unlock_notify(). There is however,
8791: ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
8792: ** SQLite checks if there are any currently executing SELECT statements
8793: ** that belong to the same connection. If there are, SQLITE_LOCKED is
8794: ** returned. In this case there is no "blocking connection", so invoking
8795: ** sqlite3_unlock_notify() results in the unlock-notify callback being
8796: ** invoked immediately. If the application then re-attempts the "DROP TABLE"
8797: ** or "DROP INDEX" query, an infinite loop might be the result.
8798: **
8799: ** One way around this problem is to check the extended error code returned
8800: ** by an sqlite3_step() call. ^(If there is a blocking connection, then the
8801: ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
1.4.2.3 ! misho 8802: ** the special "DROP TABLE/INDEX" case, the extended error code is just
1.2 misho 8803: ** SQLITE_LOCKED.)^
8804: */
8805: SQLITE_API int sqlite3_unlock_notify(
8806: sqlite3 *pBlocked, /* Waiting connection */
8807: void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
8808: void *pNotifyArg /* Argument to pass to xNotify */
8809: );
8810:
8811:
8812: /*
8813: ** CAPI3REF: String Comparison
8814: **
1.3 misho 8815: ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
8816: ** and extensions to compare the contents of two buffers containing UTF-8
8817: ** strings in a case-independent fashion, using the same definition of "case
8818: ** independence" that SQLite uses internally when comparing identifiers.
1.2 misho 8819: */
1.3 misho 8820: SQLITE_API int sqlite3_stricmp(const char *, const char *);
1.2 misho 8821: SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
8822:
8823: /*
1.4 misho 8824: ** CAPI3REF: String Globbing
8825: *
8826: ** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if
8827: ** string X matches the [GLOB] pattern P.
8828: ** ^The definition of [GLOB] pattern matching used in
8829: ** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
8830: ** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function
8831: ** is case sensitive.
8832: **
8833: ** Note that this routine returns zero on a match and non-zero if the strings
8834: ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
8835: **
8836: ** See also: [sqlite3_strlike()].
8837: */
8838: SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
8839:
8840: /*
8841: ** CAPI3REF: String LIKE Matching
8842: *
8843: ** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if
8844: ** string X matches the [LIKE] pattern P with escape character E.
8845: ** ^The definition of [LIKE] pattern matching used in
8846: ** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"
8847: ** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without
8848: ** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.
8849: ** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case
8850: ** insensitive - equivalent upper and lower case ASCII characters match
8851: ** one another.
8852: **
8853: ** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though
8854: ** only ASCII characters are case folded.
8855: **
8856: ** Note that this routine returns zero on a match and non-zero if the strings
8857: ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
8858: **
8859: ** See also: [sqlite3_strglob()].
8860: */
8861: SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc);
8862:
8863: /*
1.2 misho 8864: ** CAPI3REF: Error Logging Interface
8865: **
1.4 misho 8866: ** ^The [sqlite3_log()] interface writes a message into the [error log]
1.2 misho 8867: ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
8868: ** ^If logging is enabled, the zFormat string and subsequent arguments are
8869: ** used with [sqlite3_snprintf()] to generate the final output string.
8870: **
8871: ** The sqlite3_log() interface is intended for use by extensions such as
8872: ** virtual tables, collating functions, and SQL functions. While there is
8873: ** nothing to prevent an application from calling sqlite3_log(), doing so
8874: ** is considered bad form.
8875: **
8876: ** The zFormat string must not be NULL.
8877: **
8878: ** To avoid deadlocks and other threading problems, the sqlite3_log() routine
8879: ** will not use dynamically allocated memory. The log message is stored in
8880: ** a fixed-length buffer on the stack. If the log message is longer than
8881: ** a few hundred characters, it will be truncated to the length of the
8882: ** buffer.
8883: */
8884: SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
8885:
8886: /*
8887: ** CAPI3REF: Write-Ahead Log Commit Hook
1.4 misho 8888: ** METHOD: sqlite3
1.2 misho 8889: **
8890: ** ^The [sqlite3_wal_hook()] function is used to register a callback that
1.4 misho 8891: ** is invoked each time data is committed to a database in wal mode.
1.2 misho 8892: **
1.4.2.3 ! misho 8893: ** ^(The callback is invoked by SQLite after the commit has taken place and
! 8894: ** the associated write-lock on the database released)^, so the implementation
1.2 misho 8895: ** may read, write or [checkpoint] the database as required.
8896: **
8897: ** ^The first parameter passed to the callback function when it is invoked
8898: ** is a copy of the third parameter passed to sqlite3_wal_hook() when
8899: ** registering the callback. ^The second is a copy of the database handle.
8900: ** ^The third parameter is the name of the database that was written to -
8901: ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
8902: ** is the number of pages currently in the write-ahead log file,
8903: ** including those that were just committed.
8904: **
8905: ** The callback function should normally return [SQLITE_OK]. ^If an error
8906: ** code is returned, that error will propagate back up through the
8907: ** SQLite code base to cause the statement that provoked the callback
8908: ** to report an error, though the commit will have still occurred. If the
8909: ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
8910: ** that does not correspond to any valid SQLite error code, the results
8911: ** are undefined.
8912: **
1.4.2.3 ! misho 8913: ** A single database handle may have at most a single write-ahead log callback
1.2 misho 8914: ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
8915: ** previously registered write-ahead log callback. ^Note that the
8916: ** [sqlite3_wal_autocheckpoint()] interface and the
8917: ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
1.4 misho 8918: ** overwrite any prior [sqlite3_wal_hook()] settings.
1.2 misho 8919: */
8920: SQLITE_API void *sqlite3_wal_hook(
1.4.2.3 ! misho 8921: sqlite3*,
1.2 misho 8922: int(*)(void *,sqlite3*,const char*,int),
8923: void*
8924: );
8925:
8926: /*
8927: ** CAPI3REF: Configure an auto-checkpoint
1.4 misho 8928: ** METHOD: sqlite3
1.2 misho 8929: **
8930: ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
8931: ** [sqlite3_wal_hook()] that causes any database on [database connection] D
8932: ** to automatically [checkpoint]
8933: ** after committing a transaction if there are N or
1.4.2.3 ! misho 8934: ** more frames in the [write-ahead log] file. ^Passing zero or
1.2 misho 8935: ** a negative value as the nFrame parameter disables automatic
8936: ** checkpoints entirely.
8937: **
8938: ** ^The callback registered by this function replaces any existing callback
8939: ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
8940: ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
8941: ** configured by this function.
8942: **
8943: ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
8944: ** from SQL.
8945: **
1.4 misho 8946: ** ^Checkpoints initiated by this mechanism are
8947: ** [sqlite3_wal_checkpoint_v2|PASSIVE].
8948: **
1.2 misho 8949: ** ^Every new [database connection] defaults to having the auto-checkpoint
8950: ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
8951: ** pages. The use of this interface
8952: ** is only necessary if the default setting is found to be suboptimal
8953: ** for a particular application.
8954: */
8955: SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
8956:
8957: /*
8958: ** CAPI3REF: Checkpoint a database
1.4 misho 8959: ** METHOD: sqlite3
1.2 misho 8960: **
1.4 misho 8961: ** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to
8962: ** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^
1.2 misho 8963: **
1.4.2.3 ! misho 8964: ** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the
1.4 misho 8965: ** [write-ahead log] for database X on [database connection] D to be
8966: ** transferred into the database file and for the write-ahead log to
8967: ** be reset. See the [checkpointing] documentation for addition
8968: ** information.
8969: **
8970: ** This interface used to be the only way to cause a checkpoint to
8971: ** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]
8972: ** interface was added. This interface is retained for backwards
8973: ** compatibility and as a convenience for applications that need to manually
8974: ** start a callback but which do not need the full power (and corresponding
8975: ** complication) of [sqlite3_wal_checkpoint_v2()].
1.2 misho 8976: */
8977: SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
8978:
8979: /*
8980: ** CAPI3REF: Checkpoint a database
1.4 misho 8981: ** METHOD: sqlite3
1.2 misho 8982: **
1.4 misho 8983: ** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint
8984: ** operation on database X of [database connection] D in mode M. Status
8985: ** information is written back into integers pointed to by L and C.)^
8986: ** ^(The M parameter must be a valid [checkpoint mode]:)^
1.2 misho 8987: **
8988: ** <dl>
8989: ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
1.4.2.3 ! misho 8990: ** ^Checkpoint as many frames as possible without waiting for any database
! 8991: ** readers or writers to finish, then sync the database file if all frames
1.4 misho 8992: ** in the log were checkpointed. ^The [busy-handler callback]
1.4.2.3 ! misho 8993: ** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode.
1.4 misho 8994: ** ^On the other hand, passive mode might leave the checkpoint unfinished
8995: ** if there are concurrent readers or writers.
1.2 misho 8996: **
8997: ** <dt>SQLITE_CHECKPOINT_FULL<dd>
1.4 misho 8998: ** ^This mode blocks (it invokes the
8999: ** [sqlite3_busy_handler|busy-handler callback]) until there is no
1.2 misho 9000: ** database writer and all readers are reading from the most recent database
1.4 misho 9001: ** snapshot. ^It then checkpoints all frames in the log file and syncs the
9002: ** database file. ^This mode blocks new database writers while it is pending,
9003: ** but new database readers are allowed to continue unimpeded.
1.2 misho 9004: **
9005: ** <dt>SQLITE_CHECKPOINT_RESTART<dd>
1.4 misho 9006: ** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition
1.4.2.3 ! misho 9007: ** that after checkpointing the log file it blocks (calls the
1.4 misho 9008: ** [busy-handler callback])
1.4.2.3 ! misho 9009: ** until all readers are reading from the database file only. ^This ensures
1.4 misho 9010: ** that the next writer will restart the log file from the beginning.
9011: ** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new
9012: ** database writer attempts while it is pending, but does not impede readers.
9013: **
9014: ** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd>
9015: ** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the
9016: ** addition that it also truncates the log file to zero bytes just prior
9017: ** to a successful return.
1.2 misho 9018: ** </dl>
9019: **
1.4 misho 9020: ** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in
9021: ** the log file or to -1 if the checkpoint could not run because
9022: ** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not
9023: ** NULL,then *pnCkpt is set to the total number of checkpointed frames in the
9024: ** log file (including any that were already checkpointed before the function
9025: ** was called) or to -1 if the checkpoint could not run due to an error or
9026: ** because the database is not in WAL mode. ^Note that upon successful
9027: ** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been
9028: ** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.
1.2 misho 9029: **
1.4 misho 9030: ** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If
1.4.2.3 ! misho 9031: ** any other process is running a checkpoint operation at the same time, the
! 9032: ** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a
1.2 misho 9033: ** busy-handler configured, it will not be invoked in this case.
9034: **
1.4.2.3 ! misho 9035: ** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the
1.4 misho 9036: ** exclusive "writer" lock on the database file. ^If the writer lock cannot be
9037: ** obtained immediately, and a busy-handler is configured, it is invoked and
9038: ** the writer lock retried until either the busy-handler returns 0 or the lock
9039: ** is successfully obtained. ^The busy-handler is also invoked while waiting for
9040: ** database readers as described above. ^If the busy-handler returns 0 before
1.2 misho 9041: ** the writer lock is obtained or while waiting for database readers, the
1.4.2.3 ! misho 9042: ** checkpoint operation proceeds from that point in the same way as
! 9043: ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
1.4 misho 9044: ** without blocking any further. ^SQLITE_BUSY is returned in this case.
1.2 misho 9045: **
1.4 misho 9046: ** ^If parameter zDb is NULL or points to a zero length string, then the
1.4.2.3 ! misho 9047: ** specified operation is attempted on all WAL databases [attached] to
1.4 misho 9048: ** [database connection] db. In this case the
1.4.2.3 ! misho 9049: ** values written to output parameters *pnLog and *pnCkpt are undefined. ^If
! 9050: ** an SQLITE_BUSY error is encountered when processing one or more of the
! 9051: ** attached WAL databases, the operation is still attempted on any remaining
! 9052: ** attached databases and SQLITE_BUSY is returned at the end. ^If any other
! 9053: ** error occurs while processing an attached database, processing is abandoned
! 9054: ** and the error code is returned to the caller immediately. ^If no error
! 9055: ** (SQLITE_BUSY or otherwise) is encountered while processing the attached
1.2 misho 9056: ** databases, SQLITE_OK is returned.
9057: **
1.4 misho 9058: ** ^If database zDb is the name of an attached database that is not in WAL
9059: ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If
1.2 misho 9060: ** zDb is not NULL (or a zero length string) and is not the name of any
9061: ** attached database, SQLITE_ERROR is returned to the caller.
1.4 misho 9062: **
9063: ** ^Unless it returns SQLITE_MISUSE,
9064: ** the sqlite3_wal_checkpoint_v2() interface
9065: ** sets the error information that is queried by
9066: ** [sqlite3_errcode()] and [sqlite3_errmsg()].
9067: **
9068: ** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface
9069: ** from SQL.
1.2 misho 9070: */
9071: SQLITE_API int sqlite3_wal_checkpoint_v2(
9072: sqlite3 *db, /* Database handle */
9073: const char *zDb, /* Name of attached database (or NULL) */
9074: int eMode, /* SQLITE_CHECKPOINT_* value */
9075: int *pnLog, /* OUT: Size of WAL log in frames */
9076: int *pnCkpt /* OUT: Total number of frames checkpointed */
9077: );
9078:
9079: /*
1.4 misho 9080: ** CAPI3REF: Checkpoint Mode Values
9081: ** KEYWORDS: {checkpoint mode}
1.2 misho 9082: **
1.4 misho 9083: ** These constants define all valid values for the "checkpoint mode" passed
9084: ** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.
9085: ** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the
9086: ** meaning of each of these checkpoint modes.
9087: */
9088: #define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */
9089: #define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */
9090: #define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for for readers */
9091: #define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */
1.2 misho 9092:
9093: /*
9094: ** CAPI3REF: Virtual Table Interface Configuration
9095: **
9096: ** This function may be called by either the [xConnect] or [xCreate] method
9097: ** of a [virtual table] implementation to configure
9098: ** various facets of the virtual table interface.
9099: **
9100: ** If this interface is invoked outside the context of an xConnect or
9101: ** xCreate virtual table method then the behavior is undefined.
9102: **
1.4.2.3 ! misho 9103: ** In the call sqlite3_vtab_config(D,C,...) the D parameter is the
! 9104: ** [database connection] in which the virtual table is being created and
! 9105: ** which is passed in as the first argument to the [xConnect] or [xCreate]
! 9106: ** method that is invoking sqlite3_vtab_config(). The C parameter is one
! 9107: ** of the [virtual table configuration options]. The presence and meaning
! 9108: ** of parameters after C depend on which [virtual table configuration option]
! 9109: ** is used.
1.2 misho 9110: */
9111: SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
9112:
9113: /*
9114: ** CAPI3REF: Virtual Table Configuration Options
1.4.2.3 ! misho 9115: ** KEYWORDS: {virtual table configuration options}
! 9116: ** KEYWORDS: {virtual table configuration option}
1.2 misho 9117: **
9118: ** These macros define the various options to the
9119: ** [sqlite3_vtab_config()] interface that [virtual table] implementations
9120: ** can use to customize and optimize their behavior.
9121: **
9122: ** <dl>
1.4.2.2 misho 9123: ** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]]
1.4.2.3 ! misho 9124: ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt>
1.2 misho 9125: ** <dd>Calls of the form
9126: ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
9127: ** where X is an integer. If X is zero, then the [virtual table] whose
9128: ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
9129: ** support constraints. In this configuration (which is the default) if
9130: ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
9131: ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
9132: ** specified as part of the users SQL statement, regardless of the actual
9133: ** ON CONFLICT mode specified.
9134: **
9135: ** If X is non-zero, then the virtual table implementation guarantees
9136: ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
9137: ** any modifications to internal or persistent data structures have been made.
1.4.2.3 ! misho 9138: ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
1.2 misho 9139: ** is able to roll back a statement or database transaction, and abandon
1.4.2.3 ! misho 9140: ** or continue processing the current SQL statement as appropriate.
1.2 misho 9141: ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
9142: ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
9143: ** had been ABORT.
9144: **
9145: ** Virtual table implementations that are required to handle OR REPLACE
1.4.2.3 ! misho 9146: ** must do so within the [xUpdate] method. If a call to the
! 9147: ** [sqlite3_vtab_on_conflict()] function indicates that the current ON
! 9148: ** CONFLICT policy is REPLACE, the virtual table implementation should
1.2 misho 9149: ** silently replace the appropriate rows within the xUpdate callback and
9150: ** return SQLITE_OK. Or, if this is not possible, it may return
1.4.2.3 ! misho 9151: ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
1.2 misho 9152: ** constraint handling.
1.4.2.3 ! misho 9153: ** </dd>
! 9154: **
! 9155: ** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt>
! 9156: ** <dd>Calls of the form
! 9157: ** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the
! 9158: ** the [xConnect] or [xCreate] methods of a [virtual table] implmentation
! 9159: ** prohibits that virtual table from being used from within triggers and
! 9160: ** views.
! 9161: ** </dd>
! 9162: **
! 9163: ** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt>
! 9164: ** <dd>Calls of the form
! 9165: ** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the
! 9166: ** the [xConnect] or [xCreate] methods of a [virtual table] implmentation
! 9167: ** identify that virtual table as being safe to use from within triggers
! 9168: ** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the
! 9169: ** virtual table can do no serious harm even if it is controlled by a
! 9170: ** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS
! 9171: ** flag unless absolutely necessary.
! 9172: ** </dd>
1.2 misho 9173: ** </dl>
9174: */
9175: #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
1.4.2.3 ! misho 9176: #define SQLITE_VTAB_INNOCUOUS 2
! 9177: #define SQLITE_VTAB_DIRECTONLY 3
1.2 misho 9178:
9179: /*
9180: ** CAPI3REF: Determine The Virtual Table Conflict Policy
9181: **
9182: ** This function may only be called from within a call to the [xUpdate] method
9183: ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
9184: ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
9185: ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
9186: ** of the SQL statement that triggered the call to the [xUpdate] method of the
9187: ** [virtual table].
9188: */
9189: SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
9190:
9191: /*
1.4.2.2 misho 9192: ** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE
9193: **
9194: ** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn]
9195: ** method of a [virtual table], then it returns true if and only if the
9196: ** column is being fetched as part of an UPDATE operation during which the
9197: ** column value will not change. Applications might use this to substitute
9198: ** a return value that is less expensive to compute and that the corresponding
9199: ** [xUpdate] method understands as a "no-change" value.
9200: **
9201: ** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that
9202: ** the column is not changed by the UPDATE statement, then the xColumn
9203: ** method can optionally return without setting a result, without calling
9204: ** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces].
9205: ** In that case, [sqlite3_value_nochange(X)] will return true for the
9206: ** same column in the [xUpdate] method.
9207: */
9208: SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*);
9209:
9210: /*
9211: ** CAPI3REF: Determine The Collation For a Virtual Table Constraint
9212: **
9213: ** This function may only be called from within a call to the [xBestIndex]
1.4.2.3 ! misho 9214: ** method of a [virtual table].
1.4.2.2 misho 9215: **
9216: ** The first argument must be the sqlite3_index_info object that is the
9217: ** first parameter to the xBestIndex() method. The second argument must be
9218: ** an index into the aConstraint[] array belonging to the sqlite3_index_info
1.4.2.3 ! misho 9219: ** structure passed to xBestIndex. This function returns a pointer to a buffer
1.4.2.2 misho 9220: ** containing the name of the collation sequence for the corresponding
9221: ** constraint.
9222: */
9223: SQLITE_API SQLITE_EXPERIMENTAL const char *sqlite3_vtab_collation(sqlite3_index_info*,int);
9224:
9225: /*
1.2 misho 9226: ** CAPI3REF: Conflict resolution modes
1.4 misho 9227: ** KEYWORDS: {conflict resolution mode}
1.2 misho 9228: **
9229: ** These constants are returned by [sqlite3_vtab_on_conflict()] to
9230: ** inform a [virtual table] implementation what the [ON CONFLICT] mode
9231: ** is for the SQL statement being evaluated.
9232: **
9233: ** Note that the [SQLITE_IGNORE] constant is also used as a potential
9234: ** return value from the [sqlite3_set_authorizer()] callback and that
9235: ** [SQLITE_ABORT] is also a [result code].
9236: */
9237: #define SQLITE_ROLLBACK 1
9238: /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
9239: #define SQLITE_FAIL 3
9240: /* #define SQLITE_ABORT 4 // Also an error code */
9241: #define SQLITE_REPLACE 5
9242:
1.4 misho 9243: /*
9244: ** CAPI3REF: Prepared Statement Scan Status Opcodes
9245: ** KEYWORDS: {scanstatus options}
9246: **
9247: ** The following constants can be used for the T parameter to the
9248: ** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a
9249: ** different metric for sqlite3_stmt_scanstatus() to return.
9250: **
9251: ** When the value returned to V is a string, space to hold that string is
9252: ** managed by the prepared statement S and will be automatically freed when
9253: ** S is finalized.
9254: **
9255: ** <dl>
9256: ** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>
1.4.2.3 ! misho 9257: ** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be
1.4 misho 9258: ** set to the total number of times that the X-th loop has run.</dd>
9259: **
9260: ** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt>
1.4.2.3 ! misho 9261: ** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set
1.4 misho 9262: ** to the total number of rows examined by all iterations of the X-th loop.</dd>
9263: **
9264: ** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt>
1.4.2.3 ! misho 9265: ** <dd>^The "double" variable pointed to by the V parameter will be set to the
1.4 misho 9266: ** query planner's estimate for the average number of rows output from each
9267: ** iteration of the X-th loop. If the query planner's estimates was accurate,
9268: ** then this value will approximate the quotient NVISIT/NLOOP and the
9269: ** product of this value for all prior loops with the same SELECTID will
9270: ** be the NLOOP value for the current loop.
9271: **
9272: ** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt>
1.4.2.3 ! misho 9273: ** <dd>^The "const char *" variable pointed to by the V parameter will be set
1.4 misho 9274: ** to a zero-terminated UTF-8 string containing the name of the index or table
9275: ** used for the X-th loop.
9276: **
9277: ** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>
1.4.2.3 ! misho 9278: ** <dd>^The "const char *" variable pointed to by the V parameter will be set
1.4 misho 9279: ** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]
9280: ** description for the X-th loop.
9281: **
9282: ** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt>
1.4.2.3 ! misho 9283: ** <dd>^The "int" variable pointed to by the V parameter will be set to the
1.4 misho 9284: ** "select-id" for the X-th loop. The select-id identifies which query or
9285: ** subquery the loop is part of. The main query has a select-id of zero.
9286: ** The select-id is the same value as is output in the first column
9287: ** of an [EXPLAIN QUERY PLAN] query.
9288: ** </dl>
9289: */
9290: #define SQLITE_SCANSTAT_NLOOP 0
9291: #define SQLITE_SCANSTAT_NVISIT 1
9292: #define SQLITE_SCANSTAT_EST 2
9293: #define SQLITE_SCANSTAT_NAME 3
9294: #define SQLITE_SCANSTAT_EXPLAIN 4
9295: #define SQLITE_SCANSTAT_SELECTID 5
9296:
9297: /*
9298: ** CAPI3REF: Prepared Statement Scan Status
9299: ** METHOD: sqlite3_stmt
9300: **
9301: ** This interface returns information about the predicted and measured
9302: ** performance for pStmt. Advanced applications can use this
9303: ** interface to compare the predicted and the measured performance and
9304: ** issue warnings and/or rerun [ANALYZE] if discrepancies are found.
9305: **
9306: ** Since this interface is expected to be rarely used, it is only
9307: ** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]
9308: ** compile-time option.
9309: **
9310: ** The "iScanStatusOp" parameter determines which status information to return.
9311: ** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior
9312: ** of this interface is undefined.
9313: ** ^The requested measurement is written into a variable pointed to by
9314: ** the "pOut" parameter.
9315: ** Parameter "idx" identifies the specific loop to retrieve statistics for.
9316: ** Loops are numbered starting from zero. ^If idx is out of range - less than
9317: ** zero or greater than or equal to the total number of loops used to implement
9318: ** the statement - a non-zero value is returned and the variable that pOut
9319: ** points to is unchanged.
9320: **
9321: ** ^Statistics might not be available for all loops in all statements. ^In cases
9322: ** where there exist loops with no available statistics, this function behaves
9323: ** as if the loop did not exist - it returns non-zero and leave the variable
9324: ** that pOut points to unchanged.
9325: **
9326: ** See also: [sqlite3_stmt_scanstatus_reset()]
9327: */
9328: SQLITE_API int sqlite3_stmt_scanstatus(
9329: sqlite3_stmt *pStmt, /* Prepared statement for which info desired */
9330: int idx, /* Index of loop to report on */
9331: int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */
9332: void *pOut /* Result written here */
1.4.2.3 ! misho 9333: );
1.4 misho 9334:
9335: /*
9336: ** CAPI3REF: Zero Scan-Status Counters
9337: ** METHOD: sqlite3_stmt
9338: **
9339: ** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
9340: **
9341: ** This API is only available if the library is built with pre-processor
9342: ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
9343: */
9344: SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
9345:
9346: /*
9347: ** CAPI3REF: Flush caches to disk mid-transaction
9348: **
9349: ** ^If a write-transaction is open on [database connection] D when the
9350: ** [sqlite3_db_cacheflush(D)] interface invoked, any dirty
1.4.2.3 ! misho 9351: ** pages in the pager-cache that are not currently in use are written out
1.4 misho 9352: ** to disk. A dirty page may be in use if a database cursor created by an
9353: ** active SQL statement is reading from it, or if it is page 1 of a database
9354: ** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)]
9355: ** interface flushes caches for all schemas - "main", "temp", and
9356: ** any [attached] databases.
9357: **
1.4.2.3 ! misho 9358: ** ^If this function needs to obtain extra database locks before dirty pages
! 9359: ** can be flushed to disk, it does so. ^If those locks cannot be obtained
1.4 misho 9360: ** immediately and there is a busy-handler callback configured, it is invoked
9361: ** in the usual manner. ^If the required lock still cannot be obtained, then
9362: ** the database is skipped and an attempt made to flush any dirty pages
9363: ** belonging to the next (if any) database. ^If any databases are skipped
9364: ** because locks cannot be obtained, but no other error occurs, this
9365: ** function returns SQLITE_BUSY.
9366: **
9367: ** ^If any other error occurs while flushing dirty pages to disk (for
9368: ** example an IO error or out-of-memory condition), then processing is
9369: ** abandoned and an SQLite [error code] is returned to the caller immediately.
9370: **
9371: ** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK.
9372: **
9373: ** ^This function does not set the database handle error code or message
9374: ** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions.
9375: */
9376: SQLITE_API int sqlite3_db_cacheflush(sqlite3*);
9377:
9378: /*
9379: ** CAPI3REF: The pre-update hook.
9380: **
9381: ** ^These interfaces are only available if SQLite is compiled using the
9382: ** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option.
9383: **
9384: ** ^The [sqlite3_preupdate_hook()] interface registers a callback function
9385: ** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation
1.4.2.1 misho 9386: ** on a database table.
1.4 misho 9387: ** ^At most one preupdate hook may be registered at a time on a single
9388: ** [database connection]; each call to [sqlite3_preupdate_hook()] overrides
9389: ** the previous setting.
9390: ** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()]
9391: ** with a NULL pointer as the second parameter.
9392: ** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as
9393: ** the first parameter to callbacks.
9394: **
1.4.2.1 misho 9395: ** ^The preupdate hook only fires for changes to real database tables; the
9396: ** preupdate hook is not invoked for changes to [virtual tables] or to
1.4.2.3 ! misho 9397: ** system tables like sqlite_sequence or sqlite_stat1.
1.4 misho 9398: **
9399: ** ^The second parameter to the preupdate callback is a pointer to
9400: ** the [database connection] that registered the preupdate hook.
9401: ** ^The third parameter to the preupdate callback is one of the constants
9402: ** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the
9403: ** kind of update operation that is about to occur.
9404: ** ^(The fourth parameter to the preupdate callback is the name of the
9405: ** database within the database connection that is being modified. This
1.4.2.3 ! misho 9406: ** will be "main" for the main database or "temp" for TEMP tables or
1.4 misho 9407: ** the name given after the AS keyword in the [ATTACH] statement for attached
9408: ** databases.)^
9409: ** ^The fifth parameter to the preupdate callback is the name of the
9410: ** table that is being modified.
1.4.2.1 misho 9411: **
9412: ** For an UPDATE or DELETE operation on a [rowid table], the sixth
1.4.2.3 ! misho 9413: ** parameter passed to the preupdate callback is the initial [rowid] of the
1.4.2.1 misho 9414: ** row being modified or deleted. For an INSERT operation on a rowid table,
1.4.2.3 ! misho 9415: ** or any operation on a WITHOUT ROWID table, the value of the sixth
1.4.2.1 misho 9416: ** parameter is undefined. For an INSERT or UPDATE on a rowid table the
9417: ** seventh parameter is the final rowid value of the row being inserted
9418: ** or updated. The value of the seventh parameter passed to the callback
9419: ** function is not defined for operations on WITHOUT ROWID tables, or for
9420: ** INSERT operations on rowid tables.
1.4 misho 9421: **
9422: ** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()],
9423: ** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces
9424: ** provide additional information about a preupdate event. These routines
9425: ** may only be called from within a preupdate callback. Invoking any of
9426: ** these routines from outside of a preupdate callback or with a
9427: ** [database connection] pointer that is different from the one supplied
9428: ** to the preupdate callback results in undefined and probably undesirable
9429: ** behavior.
9430: **
9431: ** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns
9432: ** in the row that is being inserted, updated, or deleted.
9433: **
9434: ** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to
9435: ** a [protected sqlite3_value] that contains the value of the Nth column of
9436: ** the table row before it is updated. The N parameter must be between 0
9437: ** and one less than the number of columns or the behavior will be
9438: ** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE
9439: ** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the
9440: ** behavior is undefined. The [sqlite3_value] that P points to
9441: ** will be destroyed when the preupdate callback returns.
9442: **
9443: ** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to
9444: ** a [protected sqlite3_value] that contains the value of the Nth column of
9445: ** the table row after it is updated. The N parameter must be between 0
9446: ** and one less than the number of columns or the behavior will be
9447: ** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE
9448: ** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the
9449: ** behavior is undefined. The [sqlite3_value] that P points to
9450: ** will be destroyed when the preupdate callback returns.
9451: **
9452: ** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate
9453: ** callback was invoked as a result of a direct insert, update, or delete
1.4.2.3 ! misho 9454: ** operation; or 1 for inserts, updates, or deletes invoked by top-level
1.4 misho 9455: ** triggers; or 2 for changes resulting from triggers called by top-level
9456: ** triggers; and so forth.
9457: **
9458: ** See also: [sqlite3_update_hook()]
9459: */
1.4.2.1 misho 9460: #if defined(SQLITE_ENABLE_PREUPDATE_HOOK)
9461: SQLITE_API void *sqlite3_preupdate_hook(
1.4 misho 9462: sqlite3 *db,
9463: void(*xPreUpdate)(
9464: void *pCtx, /* Copy of third arg to preupdate_hook() */
9465: sqlite3 *db, /* Database handle */
9466: int op, /* SQLITE_UPDATE, DELETE or INSERT */
9467: char const *zDb, /* Database name */
9468: char const *zName, /* Table name */
9469: sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */
9470: sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */
9471: ),
9472: void*
9473: );
1.4.2.1 misho 9474: SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **);
9475: SQLITE_API int sqlite3_preupdate_count(sqlite3 *);
9476: SQLITE_API int sqlite3_preupdate_depth(sqlite3 *);
9477: SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **);
9478: #endif
1.4 misho 9479:
9480: /*
9481: ** CAPI3REF: Low-level system error code
9482: **
9483: ** ^Attempt to return the underlying operating system error code or error
9484: ** number that caused the most recent I/O error or failure to open a file.
9485: ** The return value is OS-dependent. For example, on unix systems, after
9486: ** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be
9487: ** called to get back the underlying "errno" that caused the problem, such
1.4.2.3 ! misho 9488: ** as ENOSPC, EAUTH, EISDIR, and so forth.
1.4 misho 9489: */
9490: SQLITE_API int sqlite3_system_errno(sqlite3*);
9491:
9492: /*
9493: ** CAPI3REF: Database Snapshot
1.4.2.1 misho 9494: ** KEYWORDS: {snapshot} {sqlite3_snapshot}
1.4 misho 9495: **
9496: ** An instance of the snapshot object records the state of a [WAL mode]
9497: ** database for some specific point in history.
9498: **
9499: ** In [WAL mode], multiple [database connections] that are open on the
9500: ** same database file can each be reading a different historical version
9501: ** of the database file. When a [database connection] begins a read
9502: ** transaction, that connection sees an unchanging copy of the database
9503: ** as it existed for the point in time when the transaction first started.
9504: ** Subsequent changes to the database from other connections are not seen
9505: ** by the reader until a new read transaction is started.
9506: **
9507: ** The sqlite3_snapshot object records state information about an historical
9508: ** version of the database file so that it is possible to later open a new read
9509: ** transaction that sees that historical version of the database rather than
9510: ** the most recent version.
9511: */
1.4.2.1 misho 9512: typedef struct sqlite3_snapshot {
9513: unsigned char hidden[48];
9514: } sqlite3_snapshot;
1.4 misho 9515:
9516: /*
9517: ** CAPI3REF: Record A Database Snapshot
1.4.2.2 misho 9518: ** CONSTRUCTOR: sqlite3_snapshot
1.4 misho 9519: **
9520: ** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a
9521: ** new [sqlite3_snapshot] object that records the current state of
9522: ** schema S in database connection D. ^On success, the
9523: ** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly
9524: ** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.
1.4.2.1 misho 9525: ** If there is not already a read-transaction open on schema S when
1.4.2.3 ! misho 9526: ** this function is called, one is opened automatically.
1.4.2.1 misho 9527: **
9528: ** The following must be true for this function to succeed. If any of
9529: ** the following statements are false when sqlite3_snapshot_get() is
9530: ** called, SQLITE_ERROR is returned. The final value of *P is undefined
1.4.2.3 ! misho 9531: ** in this case.
1.4.2.1 misho 9532: **
9533: ** <ul>
1.4.2.2 misho 9534: ** <li> The database handle must not be in [autocommit mode].
1.4.2.1 misho 9535: **
9536: ** <li> Schema S of [database connection] D must be a [WAL mode] database.
9537: **
9538: ** <li> There must not be a write transaction open on schema S of database
9539: ** connection D.
9540: **
9541: ** <li> One or more transactions must have been written to the current wal
9542: ** file since it was created on disk (by any connection). This means
1.4.2.3 ! misho 9543: ** that a snapshot cannot be taken on a wal mode database with no wal
1.4.2.1 misho 9544: ** file immediately after it is first opened. At least one transaction
9545: ** must be written to it first.
9546: ** </ul>
9547: **
9548: ** This function may also return SQLITE_NOMEM. If it is called with the
1.4.2.3 ! misho 9549: ** database handle in autocommit mode but fails for some other reason,
1.4.2.1 misho 9550: ** whether or not a read transaction is opened on schema S is undefined.
1.4 misho 9551: **
9552: ** The [sqlite3_snapshot] object returned from a successful call to
9553: ** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]
9554: ** to avoid a memory leak.
9555: **
9556: ** The [sqlite3_snapshot_get()] interface is only available when the
1.4.2.2 misho 9557: ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
1.4 misho 9558: */
9559: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get(
9560: sqlite3 *db,
9561: const char *zSchema,
9562: sqlite3_snapshot **ppSnapshot
9563: );
9564:
9565: /*
9566: ** CAPI3REF: Start a read transaction on an historical snapshot
1.4.2.2 misho 9567: ** METHOD: sqlite3_snapshot
9568: **
1.4.2.3 ! misho 9569: ** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read
! 9570: ** transaction or upgrades an existing one for schema S of
! 9571: ** [database connection] D such that the read transaction refers to
! 9572: ** historical [snapshot] P, rather than the most recent change to the
! 9573: ** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK
1.4.2.2 misho 9574: ** on success or an appropriate [error code] if it fails.
9575: **
1.4.2.3 ! misho 9576: ** ^In order to succeed, the database connection must not be in
1.4.2.2 misho 9577: ** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there
9578: ** is already a read transaction open on schema S, then the database handle
9579: ** must have no active statements (SELECT statements that have been passed
1.4.2.3 ! misho 9580: ** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()).
1.4.2.2 misho 9581: ** SQLITE_ERROR is returned if either of these conditions is violated, or
9582: ** if schema S does not exist, or if the snapshot object is invalid.
9583: **
9584: ** ^A call to sqlite3_snapshot_open() will fail to open if the specified
1.4.2.3 ! misho 9585: ** snapshot has been overwritten by a [checkpoint]. In this case
1.4.2.2 misho 9586: ** SQLITE_ERROR_SNAPSHOT is returned.
9587: **
1.4.2.3 ! misho 9588: ** If there is already a read transaction open when this function is
1.4.2.2 misho 9589: ** invoked, then the same read transaction remains open (on the same
9590: ** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT
9591: ** is returned. If another error code - for example SQLITE_PROTOCOL or an
9592: ** SQLITE_IOERR error code - is returned, then the final state of the
1.4.2.3 ! misho 9593: ** read transaction is undefined. If SQLITE_OK is returned, then the
1.4.2.2 misho 9594: ** read transaction is now open on database snapshot P.
1.4 misho 9595: **
9596: ** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the
9597: ** database connection D does not know that the database file for
9598: ** schema S is in [WAL mode]. A database connection might not know
9599: ** that the database file is in [WAL mode] if there has been no prior
1.4.2.3 ! misho 9600: ** I/O on that database connection, or if the database entered [WAL mode]
1.4 misho 9601: ** after the most recent I/O on the database connection.)^
9602: ** (Hint: Run "[PRAGMA application_id]" against a newly opened
9603: ** database connection in order to make it ready to use snapshots.)
9604: **
9605: ** The [sqlite3_snapshot_open()] interface is only available when the
1.4.2.2 misho 9606: ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
1.4 misho 9607: */
9608: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open(
9609: sqlite3 *db,
9610: const char *zSchema,
9611: sqlite3_snapshot *pSnapshot
9612: );
9613:
9614: /*
9615: ** CAPI3REF: Destroy a snapshot
1.4.2.2 misho 9616: ** DESTRUCTOR: sqlite3_snapshot
1.4 misho 9617: **
9618: ** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P.
9619: ** The application must eventually free every [sqlite3_snapshot] object
9620: ** using this routine to avoid a memory leak.
9621: **
9622: ** The [sqlite3_snapshot_free()] interface is only available when the
1.4.2.2 misho 9623: ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
1.4 misho 9624: */
9625: SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*);
1.2 misho 9626:
1.4 misho 9627: /*
9628: ** CAPI3REF: Compare the ages of two snapshot handles.
1.4.2.2 misho 9629: ** METHOD: sqlite3_snapshot
1.4 misho 9630: **
9631: ** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages
1.4.2.3 ! misho 9632: ** of two valid snapshot handles.
1.4 misho 9633: **
1.4.2.3 ! misho 9634: ** If the two snapshot handles are not associated with the same database
! 9635: ** file, the result of the comparison is undefined.
1.4 misho 9636: **
9637: ** Additionally, the result of the comparison is only valid if both of the
9638: ** snapshot handles were obtained by calling sqlite3_snapshot_get() since the
9639: ** last time the wal file was deleted. The wal file is deleted when the
9640: ** database is changed back to rollback mode or when the number of database
1.4.2.3 ! misho 9641: ** clients drops to zero. If either snapshot handle was obtained before the
! 9642: ** wal file was last deleted, the value returned by this function
1.4 misho 9643: ** is undefined.
9644: **
9645: ** Otherwise, this API returns a negative value if P1 refers to an older
9646: ** snapshot than P2, zero if the two handles refer to the same database
9647: ** snapshot, and a positive value if P1 is a newer snapshot than P2.
1.4.2.2 misho 9648: **
9649: ** This interface is only available if SQLite is compiled with the
9650: ** [SQLITE_ENABLE_SNAPSHOT] option.
1.4 misho 9651: */
9652: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp(
9653: sqlite3_snapshot *p1,
9654: sqlite3_snapshot *p2
9655: );
1.2 misho 9656:
9657: /*
1.4.2.1 misho 9658: ** CAPI3REF: Recover snapshots from a wal file
1.4.2.2 misho 9659: ** METHOD: sqlite3_snapshot
1.4.2.1 misho 9660: **
1.4.2.2 misho 9661: ** If a [WAL file] remains on disk after all database connections close
9662: ** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control]
9663: ** or because the last process to have the database opened exited without
9664: ** calling [sqlite3_close()]) and a new connection is subsequently opened
9665: ** on that database and [WAL file], the [sqlite3_snapshot_open()] interface
9666: ** will only be able to open the last transaction added to the WAL file
9667: ** even though the WAL file contains other valid transactions.
1.4.2.1 misho 9668: **
1.4.2.2 misho 9669: ** This function attempts to scan the WAL file associated with database zDb
1.4.2.1 misho 9670: ** of database handle db and make all valid snapshots available to
9671: ** sqlite3_snapshot_open(). It is an error if there is already a read
1.4.2.2 misho 9672: ** transaction open on the database, or if the database is not a WAL mode
1.4.2.1 misho 9673: ** database.
9674: **
9675: ** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
1.4.2.2 misho 9676: **
9677: ** This interface is only available if SQLite is compiled with the
9678: ** [SQLITE_ENABLE_SNAPSHOT] option.
1.4.2.1 misho 9679: */
9680: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb);
9681:
9682: /*
1.4.2.2 misho 9683: ** CAPI3REF: Serialize a database
9684: **
9685: ** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory
9686: ** that is a serialization of the S database on [database connection] D.
9687: ** If P is not a NULL pointer, then the size of the database in bytes
9688: ** is written into *P.
9689: **
9690: ** For an ordinary on-disk database file, the serialization is just a
9691: ** copy of the disk file. For an in-memory database or a "TEMP" database,
9692: ** the serialization is the same sequence of bytes which would be written
9693: ** to disk if that database where backed up to disk.
9694: **
9695: ** The usual case is that sqlite3_serialize() copies the serialization of
9696: ** the database into memory obtained from [sqlite3_malloc64()] and returns
9697: ** a pointer to that memory. The caller is responsible for freeing the
9698: ** returned value to avoid a memory leak. However, if the F argument
9699: ** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations
9700: ** are made, and the sqlite3_serialize() function will return a pointer
9701: ** to the contiguous memory representation of the database that SQLite
9702: ** is currently using for that database, or NULL if the no such contiguous
9703: ** memory representation of the database exists. A contiguous memory
9704: ** representation of the database will usually only exist if there has
9705: ** been a prior call to [sqlite3_deserialize(D,S,...)] with the same
9706: ** values of D and S.
1.4.2.3 ! misho 9707: ** The size of the database is written into *P even if the
1.4.2.2 misho 9708: ** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy
9709: ** of the database exists.
9710: **
9711: ** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the
9712: ** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory
9713: ** allocation error occurs.
9714: **
9715: ** This interface is only available if SQLite is compiled with the
9716: ** [SQLITE_ENABLE_DESERIALIZE] option.
9717: */
9718: SQLITE_API unsigned char *sqlite3_serialize(
9719: sqlite3 *db, /* The database connection */
9720: const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */
9721: sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */
9722: unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */
9723: );
9724:
9725: /*
9726: ** CAPI3REF: Flags for sqlite3_serialize
9727: **
9728: ** Zero or more of the following constants can be OR-ed together for
9729: ** the F argument to [sqlite3_serialize(D,S,P,F)].
9730: **
9731: ** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return
9732: ** a pointer to contiguous in-memory database that it is currently using,
9733: ** without making a copy of the database. If SQLite is not currently using
9734: ** a contiguous in-memory database, then this option causes
9735: ** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be
9736: ** using a contiguous in-memory database if it has been initialized by a
9737: ** prior call to [sqlite3_deserialize()].
9738: */
9739: #define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */
9740:
9741: /*
9742: ** CAPI3REF: Deserialize a database
9743: **
1.4.2.3 ! misho 9744: ** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the
1.4.2.2 misho 9745: ** [database connection] D to disconnect from database S and then
9746: ** reopen S as an in-memory database based on the serialization contained
9747: ** in P. The serialized database P is N bytes in size. M is the size of
9748: ** the buffer P, which might be larger than N. If M is larger than N, and
9749: ** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is
9750: ** permitted to add content to the in-memory database as long as the total
9751: ** size does not exceed M bytes.
9752: **
9753: ** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will
9754: ** invoke sqlite3_free() on the serialization buffer when the database
9755: ** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then
9756: ** SQLite will try to increase the buffer size using sqlite3_realloc64()
9757: ** if writes on the database cause it to grow larger than M bytes.
9758: **
9759: ** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the
9760: ** database is currently in a read transaction or is involved in a backup
9761: ** operation.
9762: **
1.4.2.3 ! misho 9763: ** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the
1.4.2.2 misho 9764: ** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then
9765: ** [sqlite3_free()] is invoked on argument P prior to returning.
9766: **
9767: ** This interface is only available if SQLite is compiled with the
9768: ** [SQLITE_ENABLE_DESERIALIZE] option.
9769: */
9770: SQLITE_API int sqlite3_deserialize(
9771: sqlite3 *db, /* The database connection */
9772: const char *zSchema, /* Which DB to reopen with the deserialization */
9773: unsigned char *pData, /* The serialized database content */
9774: sqlite3_int64 szDb, /* Number bytes in the deserialization */
9775: sqlite3_int64 szBuf, /* Total size of buffer pData[] */
9776: unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */
9777: );
9778:
9779: /*
9780: ** CAPI3REF: Flags for sqlite3_deserialize()
9781: **
9782: ** The following are allowed values for 6th argument (the F argument) to
9783: ** the [sqlite3_deserialize(D,S,P,N,M,F)] interface.
9784: **
9785: ** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization
9786: ** in the P argument is held in memory obtained from [sqlite3_malloc64()]
9787: ** and that SQLite should take ownership of this memory and automatically
9788: ** free it when it has finished using it. Without this flag, the caller
9789: ** is responsible for freeing any dynamically allocated memory.
9790: **
9791: ** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to
9792: ** grow the size of the database using calls to [sqlite3_realloc64()]. This
9793: ** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used.
9794: ** Without this flag, the deserialized database cannot increase in size beyond
9795: ** the number of bytes specified by the M parameter.
9796: **
9797: ** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database
9798: ** should be treated as read-only.
9799: */
9800: #define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */
9801: #define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */
9802: #define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */
9803:
9804: /*
1.2 misho 9805: ** Undo the hack that converts floating point types to integer for
9806: ** builds on processors without floating point support.
9807: */
9808: #ifdef SQLITE_OMIT_FLOATING_POINT
9809: # undef double
9810: #endif
9811:
9812: #ifdef __cplusplus
9813: } /* End of the 'extern "C"' block */
9814: #endif
1.4 misho 9815: #endif /* SQLITE3_H */
1.2 misho 9816:
1.4 misho 9817: /******** Begin file sqlite3rtree.h *********/
1.2 misho 9818: /*
9819: ** 2010 August 30
9820: **
9821: ** The author disclaims copyright to this source code. In place of
9822: ** a legal notice, here is a blessing:
9823: **
9824: ** May you do good and not evil.
9825: ** May you find forgiveness for yourself and forgive others.
9826: ** May you share freely, never taking more than you give.
9827: **
9828: *************************************************************************
9829: */
9830:
9831: #ifndef _SQLITE3RTREE_H_
9832: #define _SQLITE3RTREE_H_
9833:
9834:
9835: #ifdef __cplusplus
9836: extern "C" {
9837: #endif
9838:
9839: typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
1.4 misho 9840: typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info;
9841:
9842: /* The double-precision datatype used by RTree depends on the
9843: ** SQLITE_RTREE_INT_ONLY compile-time option.
9844: */
9845: #ifdef SQLITE_RTREE_INT_ONLY
9846: typedef sqlite3_int64 sqlite3_rtree_dbl;
9847: #else
9848: typedef double sqlite3_rtree_dbl;
9849: #endif
1.2 misho 9850:
9851: /*
9852: ** Register a geometry callback named zGeom that can be used as part of an
9853: ** R-Tree geometry query as follows:
9854: **
9855: ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
9856: */
9857: SQLITE_API int sqlite3_rtree_geometry_callback(
9858: sqlite3 *db,
9859: const char *zGeom,
1.4 misho 9860: int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*),
1.2 misho 9861: void *pContext
9862: );
9863:
9864:
9865: /*
9866: ** A pointer to a structure of the following type is passed as the first
9867: ** argument to callbacks registered using rtree_geometry_callback().
9868: */
9869: struct sqlite3_rtree_geometry {
9870: void *pContext; /* Copy of pContext passed to s_r_g_c() */
9871: int nParam; /* Size of array aParam[] */
1.4 misho 9872: sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */
1.2 misho 9873: void *pUser; /* Callback implementation user data */
9874: void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */
9875: };
9876:
1.4 misho 9877: /*
1.4.2.3 ! misho 9878: ** Register a 2nd-generation geometry callback named zScore that can be
1.4 misho 9879: ** used as part of an R-Tree geometry query as follows:
9880: **
9881: ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...)
9882: */
9883: SQLITE_API int sqlite3_rtree_query_callback(
9884: sqlite3 *db,
9885: const char *zQueryFunc,
9886: int (*xQueryFunc)(sqlite3_rtree_query_info*),
9887: void *pContext,
9888: void (*xDestructor)(void*)
9889: );
9890:
9891:
9892: /*
1.4.2.3 ! misho 9893: ** A pointer to a structure of the following type is passed as the
1.4 misho 9894: ** argument to scored geometry callback registered using
9895: ** sqlite3_rtree_query_callback().
9896: **
9897: ** Note that the first 5 fields of this structure are identical to
9898: ** sqlite3_rtree_geometry. This structure is a subclass of
9899: ** sqlite3_rtree_geometry.
9900: */
9901: struct sqlite3_rtree_query_info {
9902: void *pContext; /* pContext from when function registered */
9903: int nParam; /* Number of function parameters */
9904: sqlite3_rtree_dbl *aParam; /* value of function parameters */
9905: void *pUser; /* callback can use this, if desired */
9906: void (*xDelUser)(void*); /* function to free pUser */
9907: sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */
9908: unsigned int *anQueue; /* Number of pending entries in the queue */
9909: int nCoord; /* Number of coordinates */
9910: int iLevel; /* Level of current node or entry */
9911: int mxLevel; /* The largest iLevel value in the tree */
9912: sqlite3_int64 iRowid; /* Rowid for current entry */
9913: sqlite3_rtree_dbl rParentScore; /* Score of parent node */
9914: int eParentWithin; /* Visibility of parent node */
1.4.2.2 misho 9915: int eWithin; /* OUT: Visibility */
1.4 misho 9916: sqlite3_rtree_dbl rScore; /* OUT: Write the score here */
9917: /* The following fields are only available in 3.8.11 and later */
9918: sqlite3_value **apSqlParam; /* Original SQL values of parameters */
9919: };
9920:
9921: /*
9922: ** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
9923: */
9924: #define NOT_WITHIN 0 /* Object completely outside of query region */
9925: #define PARTLY_WITHIN 1 /* Object partially overlaps query region */
9926: #define FULLY_WITHIN 2 /* Object fully contained within query region */
9927:
1.2 misho 9928:
9929: #ifdef __cplusplus
9930: } /* end of the 'extern "C"' block */
9931: #endif
9932:
9933: #endif /* ifndef _SQLITE3RTREE_H_ */
9934:
1.4 misho 9935: /******** End of sqlite3rtree.h *********/
9936: /******** Begin file sqlite3session.h *********/
9937:
9938: #if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION)
9939: #define __SQLITESESSION_H_ 1
9940:
9941: /*
9942: ** Make sure we can call this stuff from C++.
9943: */
9944: #ifdef __cplusplus
9945: extern "C" {
9946: #endif
9947:
9948:
9949: /*
9950: ** CAPI3REF: Session Object Handle
1.4.2.2 misho 9951: **
9952: ** An instance of this object is a [session] that can be used to
9953: ** record changes to a database.
1.4 misho 9954: */
9955: typedef struct sqlite3_session sqlite3_session;
9956:
9957: /*
9958: ** CAPI3REF: Changeset Iterator Handle
1.4.2.2 misho 9959: **
9960: ** An instance of this object acts as a cursor for iterating
9961: ** over the elements of a [changeset] or [patchset].
1.4 misho 9962: */
9963: typedef struct sqlite3_changeset_iter sqlite3_changeset_iter;
9964:
9965: /*
9966: ** CAPI3REF: Create A New Session Object
1.4.2.2 misho 9967: ** CONSTRUCTOR: sqlite3_session
1.4 misho 9968: **
9969: ** Create a new session object attached to database handle db. If successful,
9970: ** a pointer to the new object is written to *ppSession and SQLITE_OK is
9971: ** returned. If an error occurs, *ppSession is set to NULL and an SQLite
9972: ** error code (e.g. SQLITE_NOMEM) is returned.
9973: **
9974: ** It is possible to create multiple session objects attached to a single
9975: ** database handle.
9976: **
9977: ** Session objects created using this function should be deleted using the
9978: ** [sqlite3session_delete()] function before the database handle that they
9979: ** are attached to is itself closed. If the database handle is closed before
9980: ** the session object is deleted, then the results of calling any session
9981: ** module function, including [sqlite3session_delete()] on the session object
9982: ** are undefined.
9983: **
9984: ** Because the session module uses the [sqlite3_preupdate_hook()] API, it
9985: ** is not possible for an application to register a pre-update hook on a
9986: ** database handle that has one or more session objects attached. Nor is
9987: ** it possible to create a session object attached to a database handle for
1.4.2.3 ! misho 9988: ** which a pre-update hook is already defined. The results of attempting
1.4 misho 9989: ** either of these things are undefined.
9990: **
9991: ** The session object will be used to create changesets for tables in
9992: ** database zDb, where zDb is either "main", or "temp", or the name of an
9993: ** attached database. It is not an error if database zDb is not attached
9994: ** to the database when the session object is created.
9995: */
1.4.2.1 misho 9996: SQLITE_API int sqlite3session_create(
1.4 misho 9997: sqlite3 *db, /* Database handle */
9998: const char *zDb, /* Name of db (e.g. "main") */
9999: sqlite3_session **ppSession /* OUT: New session object */
10000: );
10001:
10002: /*
10003: ** CAPI3REF: Delete A Session Object
1.4.2.2 misho 10004: ** DESTRUCTOR: sqlite3_session
1.4 misho 10005: **
1.4.2.3 ! misho 10006: ** Delete a session object previously allocated using
1.4 misho 10007: ** [sqlite3session_create()]. Once a session object has been deleted, the
10008: ** results of attempting to use pSession with any other session module
10009: ** function are undefined.
10010: **
10011: ** Session objects must be deleted before the database handle to which they
1.4.2.3 ! misho 10012: ** are attached is closed. Refer to the documentation for
1.4 misho 10013: ** [sqlite3session_create()] for details.
10014: */
1.4.2.1 misho 10015: SQLITE_API void sqlite3session_delete(sqlite3_session *pSession);
1.4 misho 10016:
10017:
10018: /*
10019: ** CAPI3REF: Enable Or Disable A Session Object
1.4.2.2 misho 10020: ** METHOD: sqlite3_session
1.4 misho 10021: **
10022: ** Enable or disable the recording of changes by a session object. When
10023: ** enabled, a session object records changes made to the database. When
10024: ** disabled - it does not. A newly created session object is enabled.
10025: ** Refer to the documentation for [sqlite3session_changeset()] for further
10026: ** details regarding how enabling and disabling a session object affects
10027: ** the eventual changesets.
10028: **
10029: ** Passing zero to this function disables the session. Passing a value
1.4.2.3 ! misho 10030: ** greater than zero enables it. Passing a value less than zero is a
1.4 misho 10031: ** no-op, and may be used to query the current state of the session.
10032: **
1.4.2.3 ! misho 10033: ** The return value indicates the final state of the session object: 0 if
1.4 misho 10034: ** the session is disabled, or 1 if it is enabled.
10035: */
1.4.2.1 misho 10036: SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable);
1.4 misho 10037:
10038: /*
10039: ** CAPI3REF: Set Or Clear the Indirect Change Flag
1.4.2.2 misho 10040: ** METHOD: sqlite3_session
1.4 misho 10041: **
10042: ** Each change recorded by a session object is marked as either direct or
10043: ** indirect. A change is marked as indirect if either:
10044: **
10045: ** <ul>
10046: ** <li> The session object "indirect" flag is set when the change is
10047: ** made, or
1.4.2.3 ! misho 10048: ** <li> The change is made by an SQL trigger or foreign key action
1.4 misho 10049: ** instead of directly as a result of a users SQL statement.
10050: ** </ul>
10051: **
10052: ** If a single row is affected by more than one operation within a session,
10053: ** then the change is considered indirect if all operations meet the criteria
10054: ** for an indirect change above, or direct otherwise.
10055: **
10056: ** This function is used to set, clear or query the session object indirect
10057: ** flag. If the second argument passed to this function is zero, then the
10058: ** indirect flag is cleared. If it is greater than zero, the indirect flag
10059: ** is set. Passing a value less than zero does not modify the current value
1.4.2.3 ! misho 10060: ** of the indirect flag, and may be used to query the current state of the
1.4 misho 10061: ** indirect flag for the specified session object.
10062: **
1.4.2.3 ! misho 10063: ** The return value indicates the final state of the indirect flag: 0 if
1.4 misho 10064: ** it is clear, or 1 if it is set.
10065: */
1.4.2.1 misho 10066: SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect);
1.4 misho 10067:
10068: /*
10069: ** CAPI3REF: Attach A Table To A Session Object
1.4.2.2 misho 10070: ** METHOD: sqlite3_session
1.4 misho 10071: **
10072: ** If argument zTab is not NULL, then it is the name of a table to attach
1.4.2.3 ! misho 10073: ** to the session object passed as the first argument. All subsequent changes
! 10074: ** made to the table while the session object is enabled will be recorded. See
1.4 misho 10075: ** documentation for [sqlite3session_changeset()] for further details.
10076: **
10077: ** Or, if argument zTab is NULL, then changes are recorded for all tables
1.4.2.3 ! misho 10078: ** in the database. If additional tables are added to the database (by
! 10079: ** executing "CREATE TABLE" statements) after this call is made, changes for
1.4 misho 10080: ** the new tables are also recorded.
10081: **
10082: ** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
1.4.2.3 ! misho 10083: ** defined as part of their CREATE TABLE statement. It does not matter if the
1.4 misho 10084: ** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
10085: ** KEY may consist of a single column, or may be a composite key.
1.4.2.3 ! misho 10086: **
1.4 misho 10087: ** It is not an error if the named table does not exist in the database. Nor
10088: ** is it an error if the named table does not have a PRIMARY KEY. However,
10089: ** no changes will be recorded in either of these scenarios.
10090: **
10091: ** Changes are not recorded for individual rows that have NULL values stored
10092: ** in one or more of their PRIMARY KEY columns.
10093: **
1.4.2.3 ! misho 10094: ** SQLITE_OK is returned if the call completes without error. Or, if an error
1.4 misho 10095: ** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
1.4.2.2 misho 10096: **
10097: ** <h3>Special sqlite_stat1 Handling</h3>
10098: **
1.4.2.3 ! misho 10099: ** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to
1.4.2.2 misho 10100: ** some of the rules above. In SQLite, the schema of sqlite_stat1 is:
10101: ** <pre>
1.4.2.3 ! misho 10102: ** CREATE TABLE sqlite_stat1(tbl,idx,stat)
1.4.2.2 misho 10103: ** </pre>
10104: **
1.4.2.3 ! misho 10105: ** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are
! 10106: ** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes
1.4.2.2 misho 10107: ** are recorded for rows for which (idx IS NULL) is true. However, for such
10108: ** rows a zero-length blob (SQL value X'') is stored in the changeset or
10109: ** patchset instead of a NULL value. This allows such changesets to be
10110: ** manipulated by legacy implementations of sqlite3changeset_invert(),
10111: ** concat() and similar.
10112: **
1.4.2.3 ! misho 10113: ** The sqlite3changeset_apply() function automatically converts the
1.4.2.2 misho 10114: ** zero-length blob back to a NULL value when updating the sqlite_stat1
10115: ** table. However, if the application calls sqlite3changeset_new(),
1.4.2.3 ! misho 10116: ** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset
1.4.2.2 misho 10117: ** iterator directly (including on a changeset iterator passed to a
10118: ** conflict-handler callback) then the X'' value is returned. The application
10119: ** must translate X'' to NULL itself if required.
10120: **
10121: ** Legacy (older than 3.22.0) versions of the sessions module cannot capture
10122: ** changes made to the sqlite_stat1 table. Legacy versions of the
10123: ** sqlite3changeset_apply() function silently ignore any modifications to the
10124: ** sqlite_stat1 table that are part of a changeset or patchset.
1.4 misho 10125: */
1.4.2.1 misho 10126: SQLITE_API int sqlite3session_attach(
1.4 misho 10127: sqlite3_session *pSession, /* Session object */
10128: const char *zTab /* Table name */
10129: );
10130:
10131: /*
10132: ** CAPI3REF: Set a table filter on a Session Object.
1.4.2.2 misho 10133: ** METHOD: sqlite3_session
1.4 misho 10134: **
1.4.2.3 ! misho 10135: ** The second argument (xFilter) is the "filter callback". For changes to rows
1.4.2.1 misho 10136: ** in tables that are not attached to the Session object, the filter is called
1.4.2.3 ! misho 10137: ** to determine whether changes to the table's rows should be tracked or not.
! 10138: ** If xFilter returns 0, changes are not tracked. Note that once a table is
1.4 misho 10139: ** attached, xFilter will not be called again.
10140: */
1.4.2.1 misho 10141: SQLITE_API void sqlite3session_table_filter(
1.4 misho 10142: sqlite3_session *pSession, /* Session object */
10143: int(*xFilter)(
10144: void *pCtx, /* Copy of third arg to _filter_table() */
10145: const char *zTab /* Table name */
10146: ),
10147: void *pCtx /* First argument passed to xFilter */
10148: );
10149:
10150: /*
10151: ** CAPI3REF: Generate A Changeset From A Session Object
1.4.2.2 misho 10152: ** METHOD: sqlite3_session
1.4 misho 10153: **
1.4.2.3 ! misho 10154: ** Obtain a changeset containing changes to the tables attached to the
! 10155: ** session object passed as the first argument. If successful,
! 10156: ** set *ppChangeset to point to a buffer containing the changeset
1.4 misho 10157: ** and *pnChangeset to the size of the changeset in bytes before returning
10158: ** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to
10159: ** zero and return an SQLite error code.
10160: **
10161: ** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes,
10162: ** each representing a change to a single row of an attached table. An INSERT
10163: ** change contains the values of each field of a new database row. A DELETE
10164: ** contains the original values of each field of a deleted database row. An
10165: ** UPDATE change contains the original values of each field of an updated
10166: ** database row along with the updated values for each updated non-primary-key
10167: ** column. It is not possible for an UPDATE change to represent a change that
10168: ** modifies the values of primary key columns. If such a change is made, it
10169: ** is represented in a changeset as a DELETE followed by an INSERT.
10170: **
1.4.2.3 ! misho 10171: ** Changes are not recorded for rows that have NULL values stored in one or
1.4 misho 10172: ** more of their PRIMARY KEY columns. If such a row is inserted or deleted,
10173: ** no corresponding change is present in the changesets returned by this
10174: ** function. If an existing row with one or more NULL values stored in
10175: ** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL,
10176: ** only an INSERT is appears in the changeset. Similarly, if an existing row
10177: ** with non-NULL PRIMARY KEY values is updated so that one or more of its
10178: ** PRIMARY KEY columns are set to NULL, the resulting changeset contains a
10179: ** DELETE change only.
10180: **
10181: ** The contents of a changeset may be traversed using an iterator created
10182: ** using the [sqlite3changeset_start()] API. A changeset may be applied to
10183: ** a database with a compatible schema using the [sqlite3changeset_apply()]
10184: ** API.
10185: **
10186: ** Within a changeset generated by this function, all changes related to a
10187: ** single table are grouped together. In other words, when iterating through
10188: ** a changeset or when applying a changeset to a database, all changes related
10189: ** to a single table are processed before moving on to the next table. Tables
10190: ** are sorted in the same order in which they were attached (or auto-attached)
10191: ** to the sqlite3_session object. The order in which the changes related to
10192: ** a single table are stored is undefined.
10193: **
10194: ** Following a successful call to this function, it is the responsibility of
10195: ** the caller to eventually free the buffer that *ppChangeset points to using
10196: ** [sqlite3_free()].
10197: **
10198: ** <h3>Changeset Generation</h3>
10199: **
10200: ** Once a table has been attached to a session object, the session object
10201: ** records the primary key values of all new rows inserted into the table.
10202: ** It also records the original primary key and other column values of any
10203: ** deleted or updated rows. For each unique primary key value, data is only
10204: ** recorded once - the first time a row with said primary key is inserted,
10205: ** updated or deleted in the lifetime of the session.
10206: **
10207: ** There is one exception to the previous paragraph: when a row is inserted,
10208: ** updated or deleted, if one or more of its primary key columns contain a
10209: ** NULL value, no record of the change is made.
10210: **
10211: ** The session object therefore accumulates two types of records - those
10212: ** that consist of primary key values only (created when the user inserts
10213: ** a new record) and those that consist of the primary key values and the
10214: ** original values of other table columns (created when the users deletes
10215: ** or updates a record).
10216: **
10217: ** When this function is called, the requested changeset is created using
10218: ** both the accumulated records and the current contents of the database
10219: ** file. Specifically:
10220: **
10221: ** <ul>
10222: ** <li> For each record generated by an insert, the database is queried
10223: ** for a row with a matching primary key. If one is found, an INSERT
1.4.2.3 ! misho 10224: ** change is added to the changeset. If no such row is found, no change
1.4 misho 10225: ** is added to the changeset.
10226: **
1.4.2.3 ! misho 10227: ** <li> For each record generated by an update or delete, the database is
1.4 misho 10228: ** queried for a row with a matching primary key. If such a row is
10229: ** found and one or more of the non-primary key fields have been
1.4.2.3 ! misho 10230: ** modified from their original values, an UPDATE change is added to
! 10231: ** the changeset. Or, if no such row is found in the table, a DELETE
1.4 misho 10232: ** change is added to the changeset. If there is a row with a matching
10233: ** primary key in the database, but all fields contain their original
10234: ** values, no change is added to the changeset.
10235: ** </ul>
10236: **
10237: ** This means, amongst other things, that if a row is inserted and then later
10238: ** deleted while a session object is active, neither the insert nor the delete
1.4.2.3 ! misho 10239: ** will be present in the changeset. Or if a row is deleted and then later a
1.4 misho 10240: ** row with the same primary key values inserted while a session object is
10241: ** active, the resulting changeset will contain an UPDATE change instead of
10242: ** a DELETE and an INSERT.
10243: **
10244: ** When a session object is disabled (see the [sqlite3session_enable()] API),
10245: ** it does not accumulate records when rows are inserted, updated or deleted.
10246: ** This may appear to have some counter-intuitive effects if a single row
10247: ** is written to more than once during a session. For example, if a row
1.4.2.3 ! misho 10248: ** is inserted while a session object is enabled, then later deleted while
1.4 misho 10249: ** the same session object is disabled, no INSERT record will appear in the
10250: ** changeset, even though the delete took place while the session was disabled.
1.4.2.3 ! misho 10251: ** Or, if one field of a row is updated while a session is disabled, and
1.4 misho 10252: ** another field of the same row is updated while the session is enabled, the
10253: ** resulting changeset will contain an UPDATE change that updates both fields.
10254: */
1.4.2.1 misho 10255: SQLITE_API int sqlite3session_changeset(
1.4 misho 10256: sqlite3_session *pSession, /* Session object */
10257: int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */
10258: void **ppChangeset /* OUT: Buffer containing changeset */
10259: );
10260:
10261: /*
1.4.2.2 misho 10262: ** CAPI3REF: Load The Difference Between Tables Into A Session
10263: ** METHOD: sqlite3_session
1.4 misho 10264: **
10265: ** If it is not already attached to the session object passed as the first
10266: ** argument, this function attaches table zTbl in the same manner as the
10267: ** [sqlite3session_attach()] function. If zTbl does not exist, or if it
10268: ** does not have a primary key, this function is a no-op (but does not return
10269: ** an error).
10270: **
10271: ** Argument zFromDb must be the name of a database ("main", "temp" etc.)
1.4.2.3 ! misho 10272: ** attached to the same database handle as the session object that contains
1.4 misho 10273: ** a table compatible with the table attached to the session by this function.
10274: ** A table is considered compatible if it:
10275: **
10276: ** <ul>
10277: ** <li> Has the same name,
10278: ** <li> Has the same set of columns declared in the same order, and
10279: ** <li> Has the same PRIMARY KEY definition.
10280: ** </ul>
10281: **
10282: ** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables
10283: ** are compatible but do not have any PRIMARY KEY columns, it is not an error
10284: ** but no changes are added to the session object. As with other session
10285: ** APIs, tables without PRIMARY KEYs are simply ignored.
10286: **
10287: ** This function adds a set of changes to the session object that could be
1.4.2.3 ! misho 10288: ** used to update the table in database zFrom (call this the "from-table")
! 10289: ** so that its content is the same as the table attached to the session
1.4 misho 10290: ** object (call this the "to-table"). Specifically:
10291: **
10292: ** <ul>
1.4.2.3 ! misho 10293: ** <li> For each row (primary key) that exists in the to-table but not in
1.4 misho 10294: ** the from-table, an INSERT record is added to the session object.
10295: **
1.4.2.3 ! misho 10296: ** <li> For each row (primary key) that exists in the to-table but not in
1.4 misho 10297: ** the from-table, a DELETE record is added to the session object.
10298: **
1.4.2.3 ! misho 10299: ** <li> For each row (primary key) that exists in both tables, but features
1.4.2.1 misho 10300: ** different non-PK values in each, an UPDATE record is added to the
1.4.2.3 ! misho 10301: ** session.
1.4 misho 10302: ** </ul>
10303: **
10304: ** To clarify, if this function is called and then a changeset constructed
1.4.2.3 ! misho 10305: ** using [sqlite3session_changeset()], then after applying that changeset to
! 10306: ** database zFrom the contents of the two compatible tables would be
1.4 misho 10307: ** identical.
10308: **
10309: ** It an error if database zFrom does not exist or does not contain the
10310: ** required compatible table.
10311: **
1.4.2.3 ! misho 10312: ** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite
1.4 misho 10313: ** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg
1.4.2.3 ! misho 10314: ** may be set to point to a buffer containing an English language error
1.4 misho 10315: ** message. It is the responsibility of the caller to free this buffer using
10316: ** sqlite3_free().
10317: */
1.4.2.1 misho 10318: SQLITE_API int sqlite3session_diff(
1.4 misho 10319: sqlite3_session *pSession,
10320: const char *zFromDb,
10321: const char *zTbl,
10322: char **pzErrMsg
10323: );
10324:
10325:
10326: /*
10327: ** CAPI3REF: Generate A Patchset From A Session Object
1.4.2.2 misho 10328: ** METHOD: sqlite3_session
1.4 misho 10329: **
10330: ** The differences between a patchset and a changeset are that:
10331: **
10332: ** <ul>
1.4.2.3 ! misho 10333: ** <li> DELETE records consist of the primary key fields only. The
1.4 misho 10334: ** original values of other fields are omitted.
1.4.2.3 ! misho 10335: ** <li> The original values of any modified fields are omitted from
1.4 misho 10336: ** UPDATE records.
10337: ** </ul>
10338: **
1.4.2.3 ! misho 10339: ** A patchset blob may be used with up to date versions of all
! 10340: ** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(),
1.4 misho 10341: ** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly,
10342: ** attempting to use a patchset blob with old versions of the
1.4.2.3 ! misho 10343: ** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error.
1.4 misho 10344: **
1.4.2.3 ! misho 10345: ** Because the non-primary key "old.*" fields are omitted, no
1.4 misho 10346: ** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset
10347: ** is passed to the sqlite3changeset_apply() API. Other conflict types work
10348: ** in the same way as for changesets.
10349: **
10350: ** Changes within a patchset are ordered in the same way as for changesets
10351: ** generated by the sqlite3session_changeset() function (i.e. all changes for
10352: ** a single table are grouped together, tables appear in the order in which
10353: ** they were attached to the session object).
10354: */
1.4.2.1 misho 10355: SQLITE_API int sqlite3session_patchset(
1.4 misho 10356: sqlite3_session *pSession, /* Session object */
1.4.2.2 misho 10357: int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */
10358: void **ppPatchset /* OUT: Buffer containing patchset */
1.4 misho 10359: );
10360:
10361: /*
10362: ** CAPI3REF: Test if a changeset has recorded any changes.
10363: **
1.4.2.3 ! misho 10364: ** Return non-zero if no changes to attached tables have been recorded by
! 10365: ** the session object passed as the first argument. Otherwise, if one or
1.4 misho 10366: ** more changes have been recorded, return zero.
10367: **
10368: ** Even if this function returns zero, it is possible that calling
10369: ** [sqlite3session_changeset()] on the session handle may still return a
1.4.2.3 ! misho 10370: ** changeset that contains no changes. This can happen when a row in
! 10371: ** an attached table is modified and then later on the original values
1.4 misho 10372: ** are restored. However, if this function returns non-zero, then it is
1.4.2.3 ! misho 10373: ** guaranteed that a call to sqlite3session_changeset() will return a
1.4 misho 10374: ** changeset containing zero changes.
10375: */
1.4.2.1 misho 10376: SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession);
1.4 misho 10377:
10378: /*
1.4.2.3 ! misho 10379: ** CAPI3REF: Create An Iterator To Traverse A Changeset
1.4.2.2 misho 10380: ** CONSTRUCTOR: sqlite3_changeset_iter
1.4 misho 10381: **
10382: ** Create an iterator used to iterate through the contents of a changeset.
10383: ** If successful, *pp is set to point to the iterator handle and SQLITE_OK
10384: ** is returned. Otherwise, if an error occurs, *pp is set to zero and an
10385: ** SQLite error code is returned.
10386: **
1.4.2.3 ! misho 10387: ** The following functions can be used to advance and query a changeset
1.4 misho 10388: ** iterator created by this function:
10389: **
10390: ** <ul>
10391: ** <li> [sqlite3changeset_next()]
10392: ** <li> [sqlite3changeset_op()]
10393: ** <li> [sqlite3changeset_new()]
10394: ** <li> [sqlite3changeset_old()]
10395: ** </ul>
10396: **
10397: ** It is the responsibility of the caller to eventually destroy the iterator
10398: ** by passing it to [sqlite3changeset_finalize()]. The buffer containing the
10399: ** changeset (pChangeset) must remain valid until after the iterator is
10400: ** destroyed.
10401: **
10402: ** Assuming the changeset blob was created by one of the
10403: ** [sqlite3session_changeset()], [sqlite3changeset_concat()] or
1.4.2.3 ! misho 10404: ** [sqlite3changeset_invert()] functions, all changes within the changeset
! 10405: ** that apply to a single table are grouped together. This means that when
! 10406: ** an application iterates through a changeset using an iterator created by
! 10407: ** this function, all changes that relate to a single table are visited
! 10408: ** consecutively. There is no chance that the iterator will visit a change
! 10409: ** the applies to table X, then one for table Y, and then later on visit
1.4 misho 10410: ** another change for table X.
1.4.2.2 misho 10411: **
10412: ** The behavior of sqlite3changeset_start_v2() and its streaming equivalent
10413: ** may be modified by passing a combination of
10414: ** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter.
10415: **
10416: ** Note that the sqlite3changeset_start_v2() API is still <b>experimental</b>
10417: ** and therefore subject to change.
1.4 misho 10418: */
1.4.2.1 misho 10419: SQLITE_API int sqlite3changeset_start(
1.4 misho 10420: sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */
10421: int nChangeset, /* Size of changeset blob in bytes */
10422: void *pChangeset /* Pointer to blob containing changeset */
10423: );
1.4.2.2 misho 10424: SQLITE_API int sqlite3changeset_start_v2(
10425: sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */
10426: int nChangeset, /* Size of changeset blob in bytes */
10427: void *pChangeset, /* Pointer to blob containing changeset */
10428: int flags /* SESSION_CHANGESETSTART_* flags */
10429: );
10430:
10431: /*
10432: ** CAPI3REF: Flags for sqlite3changeset_start_v2
10433: **
10434: ** The following flags may passed via the 4th parameter to
10435: ** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]:
10436: **
10437: ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd>
10438: ** Invert the changeset while iterating through it. This is equivalent to
10439: ** inverting a changeset using sqlite3changeset_invert() before applying it.
10440: ** It is an error to specify this flag with a patchset.
10441: */
10442: #define SQLITE_CHANGESETSTART_INVERT 0x0002
1.4 misho 10443:
10444:
10445: /*
10446: ** CAPI3REF: Advance A Changeset Iterator
1.4.2.2 misho 10447: ** METHOD: sqlite3_changeset_iter
1.4 misho 10448: **
1.4.2.3 ! misho 10449: ** This function may only be used with iterators created by the function
1.4 misho 10450: ** [sqlite3changeset_start()]. If it is called on an iterator passed to
10451: ** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE
10452: ** is returned and the call has no effect.
10453: **
10454: ** Immediately after an iterator is created by sqlite3changeset_start(), it
10455: ** does not point to any change in the changeset. Assuming the changeset
10456: ** is not empty, the first call to this function advances the iterator to
10457: ** point to the first change in the changeset. Each subsequent call advances
10458: ** the iterator to point to the next change in the changeset (if any). If
10459: ** no error occurs and the iterator points to a valid change after a call
1.4.2.3 ! misho 10460: ** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned.
1.4 misho 10461: ** Otherwise, if all changes in the changeset have already been visited,
10462: ** SQLITE_DONE is returned.
10463: **
1.4.2.3 ! misho 10464: ** If an error occurs, an SQLite error code is returned. Possible error
! 10465: ** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or
1.4 misho 10466: ** SQLITE_NOMEM.
10467: */
1.4.2.1 misho 10468: SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter);
1.4 misho 10469:
10470: /*
10471: ** CAPI3REF: Obtain The Current Operation From A Changeset Iterator
1.4.2.2 misho 10472: ** METHOD: sqlite3_changeset_iter
1.4 misho 10473: **
10474: ** The pIter argument passed to this function may either be an iterator
10475: ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
10476: ** created by [sqlite3changeset_start()]. In the latter case, the most recent
10477: ** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this
10478: ** is not the case, this function returns [SQLITE_MISUSE].
10479: **
10480: ** If argument pzTab is not NULL, then *pzTab is set to point to a
10481: ** nul-terminated utf-8 encoded string containing the name of the table
10482: ** affected by the current change. The buffer remains valid until either
1.4.2.3 ! misho 10483: ** sqlite3changeset_next() is called on the iterator or until the
! 10484: ** conflict-handler function returns. If pnCol is not NULL, then *pnCol is
1.4 misho 10485: ** set to the number of columns in the table affected by the change. If
1.4.2.2 misho 10486: ** pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change
1.4 misho 10487: ** is an indirect change, or false (0) otherwise. See the documentation for
10488: ** [sqlite3session_indirect()] for a description of direct and indirect
1.4.2.3 ! misho 10489: ** changes. Finally, if pOp is not NULL, then *pOp is set to one of
! 10490: ** [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], depending on the
1.4 misho 10491: ** type of change that the iterator currently points to.
10492: **
10493: ** If no error occurs, SQLITE_OK is returned. If an error does occur, an
10494: ** SQLite error code is returned. The values of the output variables may not
10495: ** be trusted in this case.
10496: */
1.4.2.1 misho 10497: SQLITE_API int sqlite3changeset_op(
1.4 misho 10498: sqlite3_changeset_iter *pIter, /* Iterator object */
10499: const char **pzTab, /* OUT: Pointer to table name */
10500: int *pnCol, /* OUT: Number of columns in table */
10501: int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */
10502: int *pbIndirect /* OUT: True for an 'indirect' change */
10503: );
10504:
10505: /*
10506: ** CAPI3REF: Obtain The Primary Key Definition Of A Table
1.4.2.2 misho 10507: ** METHOD: sqlite3_changeset_iter
1.4 misho 10508: **
10509: ** For each modified table, a changeset includes the following:
10510: **
10511: ** <ul>
10512: ** <li> The number of columns in the table, and
10513: ** <li> Which of those columns make up the tables PRIMARY KEY.
10514: ** </ul>
10515: **
10516: ** This function is used to find which columns comprise the PRIMARY KEY of
10517: ** the table modified by the change that iterator pIter currently points to.
10518: ** If successful, *pabPK is set to point to an array of nCol entries, where
10519: ** nCol is the number of columns in the table. Elements of *pabPK are set to
10520: ** 0x01 if the corresponding column is part of the tables primary key, or
10521: ** 0x00 if it is not.
10522: **
1.4.2.1 misho 10523: ** If argument pnCol is not NULL, then *pnCol is set to the number of columns
1.4 misho 10524: ** in the table.
10525: **
10526: ** If this function is called when the iterator does not point to a valid
10527: ** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise,
10528: ** SQLITE_OK is returned and the output variables populated as described
10529: ** above.
10530: */
1.4.2.1 misho 10531: SQLITE_API int sqlite3changeset_pk(
1.4 misho 10532: sqlite3_changeset_iter *pIter, /* Iterator object */
10533: unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */
10534: int *pnCol /* OUT: Number of entries in output array */
10535: );
10536:
10537: /*
10538: ** CAPI3REF: Obtain old.* Values From A Changeset Iterator
1.4.2.2 misho 10539: ** METHOD: sqlite3_changeset_iter
1.4 misho 10540: **
10541: ** The pIter argument passed to this function may either be an iterator
10542: ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
10543: ** created by [sqlite3changeset_start()]. In the latter case, the most recent
1.4.2.3 ! misho 10544: ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
1.4 misho 10545: ** Furthermore, it may only be called if the type of change that the iterator
10546: ** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise,
10547: ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
10548: **
10549: ** Argument iVal must be greater than or equal to 0, and less than the number
10550: ** of columns in the table affected by the current change. Otherwise,
10551: ** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
10552: **
10553: ** If successful, this function sets *ppValue to point to a protected
1.4.2.3 ! misho 10554: ** sqlite3_value object containing the iVal'th value from the vector of
1.4 misho 10555: ** original row values stored as part of the UPDATE or DELETE change and
1.4.2.3 ! misho 10556: ** returns SQLITE_OK. The name of the function comes from the fact that this
1.4 misho 10557: ** is similar to the "old.*" columns available to update or delete triggers.
10558: **
10559: ** If some other error occurs (e.g. an OOM condition), an SQLite error code
10560: ** is returned and *ppValue is set to NULL.
10561: */
1.4.2.1 misho 10562: SQLITE_API int sqlite3changeset_old(
1.4 misho 10563: sqlite3_changeset_iter *pIter, /* Changeset iterator */
10564: int iVal, /* Column number */
10565: sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */
10566: );
10567:
10568: /*
10569: ** CAPI3REF: Obtain new.* Values From A Changeset Iterator
1.4.2.2 misho 10570: ** METHOD: sqlite3_changeset_iter
1.4 misho 10571: **
10572: ** The pIter argument passed to this function may either be an iterator
10573: ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
10574: ** created by [sqlite3changeset_start()]. In the latter case, the most recent
1.4.2.3 ! misho 10575: ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
1.4 misho 10576: ** Furthermore, it may only be called if the type of change that the iterator
10577: ** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise,
10578: ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
10579: **
10580: ** Argument iVal must be greater than or equal to 0, and less than the number
10581: ** of columns in the table affected by the current change. Otherwise,
10582: ** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
10583: **
10584: ** If successful, this function sets *ppValue to point to a protected
1.4.2.3 ! misho 10585: ** sqlite3_value object containing the iVal'th value from the vector of
1.4 misho 10586: ** new row values stored as part of the UPDATE or INSERT change and
10587: ** returns SQLITE_OK. If the change is an UPDATE and does not include
1.4.2.3 ! misho 10588: ** a new value for the requested column, *ppValue is set to NULL and
! 10589: ** SQLITE_OK returned. The name of the function comes from the fact that
! 10590: ** this is similar to the "new.*" columns available to update or delete
1.4 misho 10591: ** triggers.
10592: **
10593: ** If some other error occurs (e.g. an OOM condition), an SQLite error code
10594: ** is returned and *ppValue is set to NULL.
10595: */
1.4.2.1 misho 10596: SQLITE_API int sqlite3changeset_new(
1.4 misho 10597: sqlite3_changeset_iter *pIter, /* Changeset iterator */
10598: int iVal, /* Column number */
10599: sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */
10600: );
10601:
10602: /*
10603: ** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator
1.4.2.2 misho 10604: ** METHOD: sqlite3_changeset_iter
1.4 misho 10605: **
10606: ** This function should only be used with iterator objects passed to a
10607: ** conflict-handler callback by [sqlite3changeset_apply()] with either
10608: ** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function
10609: ** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue
10610: ** is set to NULL.
10611: **
10612: ** Argument iVal must be greater than or equal to 0, and less than the number
10613: ** of columns in the table affected by the current change. Otherwise,
10614: ** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
10615: **
10616: ** If successful, this function sets *ppValue to point to a protected
1.4.2.3 ! misho 10617: ** sqlite3_value object containing the iVal'th value from the
1.4 misho 10618: ** "conflicting row" associated with the current conflict-handler callback
10619: ** and returns SQLITE_OK.
10620: **
10621: ** If some other error occurs (e.g. an OOM condition), an SQLite error code
10622: ** is returned and *ppValue is set to NULL.
10623: */
1.4.2.1 misho 10624: SQLITE_API int sqlite3changeset_conflict(
1.4 misho 10625: sqlite3_changeset_iter *pIter, /* Changeset iterator */
10626: int iVal, /* Column number */
10627: sqlite3_value **ppValue /* OUT: Value from conflicting row */
10628: );
10629:
10630: /*
10631: ** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations
1.4.2.2 misho 10632: ** METHOD: sqlite3_changeset_iter
1.4 misho 10633: **
10634: ** This function may only be called with an iterator passed to an
10635: ** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case
10636: ** it sets the output variable to the total number of known foreign key
10637: ** violations in the destination database and returns SQLITE_OK.
10638: **
10639: ** In all other cases this function returns SQLITE_MISUSE.
10640: */
1.4.2.1 misho 10641: SQLITE_API int sqlite3changeset_fk_conflicts(
1.4 misho 10642: sqlite3_changeset_iter *pIter, /* Changeset iterator */
10643: int *pnOut /* OUT: Number of FK violations */
10644: );
10645:
10646:
10647: /*
10648: ** CAPI3REF: Finalize A Changeset Iterator
1.4.2.2 misho 10649: ** METHOD: sqlite3_changeset_iter
1.4 misho 10650: **
10651: ** This function is used to finalize an iterator allocated with
10652: ** [sqlite3changeset_start()].
10653: **
10654: ** This function should only be called on iterators created using the
10655: ** [sqlite3changeset_start()] function. If an application calls this
10656: ** function with an iterator passed to a conflict-handler by
10657: ** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the
10658: ** call has no effect.
10659: **
10660: ** If an error was encountered within a call to an sqlite3changeset_xxx()
1.4.2.3 ! misho 10661: ** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an
1.4 misho 10662: ** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding
10663: ** to that error is returned by this function. Otherwise, SQLITE_OK is
10664: ** returned. This is to allow the following pattern (pseudo-code):
10665: **
1.4.2.2 misho 10666: ** <pre>
1.4 misho 10667: ** sqlite3changeset_start();
10668: ** while( SQLITE_ROW==sqlite3changeset_next() ){
10669: ** // Do something with change.
10670: ** }
10671: ** rc = sqlite3changeset_finalize();
10672: ** if( rc!=SQLITE_OK ){
1.4.2.3 ! misho 10673: ** // An error has occurred
1.4 misho 10674: ** }
1.4.2.2 misho 10675: ** </pre>
1.4 misho 10676: */
1.4.2.1 misho 10677: SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter);
1.4 misho 10678:
10679: /*
10680: ** CAPI3REF: Invert A Changeset
10681: **
10682: ** This function is used to "invert" a changeset object. Applying an inverted
10683: ** changeset to a database reverses the effects of applying the uninverted
10684: ** changeset. Specifically:
10685: **
10686: ** <ul>
10687: ** <li> Each DELETE change is changed to an INSERT, and
10688: ** <li> Each INSERT change is changed to a DELETE, and
10689: ** <li> For each UPDATE change, the old.* and new.* values are exchanged.
10690: ** </ul>
10691: **
10692: ** This function does not change the order in which changes appear within
10693: ** the changeset. It merely reverses the sense of each individual change.
10694: **
10695: ** If successful, a pointer to a buffer containing the inverted changeset
10696: ** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and
10697: ** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are
10698: ** zeroed and an SQLite error code returned.
10699: **
10700: ** It is the responsibility of the caller to eventually call sqlite3_free()
1.4.2.3 ! misho 10701: ** on the *ppOut pointer to free the buffer allocation following a successful
1.4 misho 10702: ** call to this function.
10703: **
10704: ** WARNING/TODO: This function currently assumes that the input is a valid
10705: ** changeset. If it is not, the results are undefined.
10706: */
1.4.2.1 misho 10707: SQLITE_API int sqlite3changeset_invert(
1.4 misho 10708: int nIn, const void *pIn, /* Input changeset */
10709: int *pnOut, void **ppOut /* OUT: Inverse of input */
10710: );
10711:
10712: /*
10713: ** CAPI3REF: Concatenate Two Changeset Objects
10714: **
1.4.2.3 ! misho 10715: ** This function is used to concatenate two changesets, A and B, into a
1.4 misho 10716: ** single changeset. The result is a changeset equivalent to applying
1.4.2.3 ! misho 10717: ** changeset A followed by changeset B.
1.4 misho 10718: **
1.4.2.3 ! misho 10719: ** This function combines the two input changesets using an
1.4 misho 10720: ** sqlite3_changegroup object. Calling it produces similar results as the
10721: ** following code fragment:
10722: **
1.4.2.2 misho 10723: ** <pre>
1.4 misho 10724: ** sqlite3_changegroup *pGrp;
10725: ** rc = sqlite3_changegroup_new(&pGrp);
10726: ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);
10727: ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);
10728: ** if( rc==SQLITE_OK ){
10729: ** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);
10730: ** }else{
10731: ** *ppOut = 0;
10732: ** *pnOut = 0;
10733: ** }
1.4.2.2 misho 10734: ** </pre>
1.4 misho 10735: **
10736: ** Refer to the sqlite3_changegroup documentation below for details.
10737: */
1.4.2.1 misho 10738: SQLITE_API int sqlite3changeset_concat(
1.4 misho 10739: int nA, /* Number of bytes in buffer pA */
10740: void *pA, /* Pointer to buffer containing changeset A */
10741: int nB, /* Number of bytes in buffer pB */
10742: void *pB, /* Pointer to buffer containing changeset B */
10743: int *pnOut, /* OUT: Number of bytes in output changeset */
10744: void **ppOut /* OUT: Buffer containing output changeset */
10745: );
10746:
10747:
10748: /*
1.4.2.1 misho 10749: ** CAPI3REF: Changegroup Handle
1.4.2.2 misho 10750: **
1.4.2.3 ! misho 10751: ** A changegroup is an object used to combine two or more
1.4.2.2 misho 10752: ** [changesets] or [patchsets]
1.4 misho 10753: */
10754: typedef struct sqlite3_changegroup sqlite3_changegroup;
10755:
10756: /*
1.4.2.1 misho 10757: ** CAPI3REF: Create A New Changegroup Object
1.4.2.2 misho 10758: ** CONSTRUCTOR: sqlite3_changegroup
1.4 misho 10759: **
10760: ** An sqlite3_changegroup object is used to combine two or more changesets
10761: ** (or patchsets) into a single changeset (or patchset). A single changegroup
10762: ** object may combine changesets or patchsets, but not both. The output is
10763: ** always in the same format as the input.
10764: **
10765: ** If successful, this function returns SQLITE_OK and populates (*pp) with
10766: ** a pointer to a new sqlite3_changegroup object before returning. The caller
1.4.2.3 ! misho 10767: ** should eventually free the returned object using a call to
1.4 misho 10768: ** sqlite3changegroup_delete(). If an error occurs, an SQLite error code
10769: ** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL.
10770: **
10771: ** The usual usage pattern for an sqlite3_changegroup object is as follows:
10772: **
10773: ** <ul>
10774: ** <li> It is created using a call to sqlite3changegroup_new().
10775: **
10776: ** <li> Zero or more changesets (or patchsets) are added to the object
10777: ** by calling sqlite3changegroup_add().
10778: **
1.4.2.3 ! misho 10779: ** <li> The result of combining all input changesets together is obtained
1.4 misho 10780: ** by the application via a call to sqlite3changegroup_output().
10781: **
10782: ** <li> The object is deleted using a call to sqlite3changegroup_delete().
10783: ** </ul>
10784: **
10785: ** Any number of calls to add() and output() may be made between the calls to
10786: ** new() and delete(), and in any order.
10787: **
1.4.2.3 ! misho 10788: ** As well as the regular sqlite3changegroup_add() and
1.4 misho 10789: ** sqlite3changegroup_output() functions, also available are the streaming
10790: ** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm().
10791: */
1.4.2.1 misho 10792: SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp);
1.4 misho 10793:
10794: /*
1.4.2.1 misho 10795: ** CAPI3REF: Add A Changeset To A Changegroup
1.4.2.2 misho 10796: ** METHOD: sqlite3_changegroup
1.4.2.1 misho 10797: **
1.4 misho 10798: ** Add all changes within the changeset (or patchset) in buffer pData (size
1.4.2.3 ! misho 10799: ** nData bytes) to the changegroup.
1.4 misho 10800: **
10801: ** If the buffer contains a patchset, then all prior calls to this function
10802: ** on the same changegroup object must also have specified patchsets. Or, if
10803: ** the buffer contains a changeset, so must have the earlier calls to this
10804: ** function. Otherwise, SQLITE_ERROR is returned and no changes are added
10805: ** to the changegroup.
10806: **
10807: ** Rows within the changeset and changegroup are identified by the values in
10808: ** their PRIMARY KEY columns. A change in the changeset is considered to
10809: ** apply to the same row as a change already present in the changegroup if
10810: ** the two rows have the same primary key.
10811: **
1.4.2.1 misho 10812: ** Changes to rows that do not already appear in the changegroup are
1.4 misho 10813: ** simply copied into it. Or, if both the new changeset and the changegroup
10814: ** contain changes that apply to a single row, the final contents of the
10815: ** changegroup depends on the type of each change, as follows:
10816: **
10817: ** <table border=1 style="margin-left:8ex;margin-right:8ex">
10818: ** <tr><th style="white-space:pre">Existing Change </th>
10819: ** <th style="white-space:pre">New Change </th>
10820: ** <th>Output Change
10821: ** <tr><td>INSERT <td>INSERT <td>
10822: ** The new change is ignored. This case does not occur if the new
10823: ** changeset was recorded immediately after the changesets already
10824: ** added to the changegroup.
10825: ** <tr><td>INSERT <td>UPDATE <td>
1.4.2.3 ! misho 10826: ** The INSERT change remains in the changegroup. The values in the
1.4 misho 10827: ** INSERT change are modified as if the row was inserted by the
10828: ** existing change and then updated according to the new change.
10829: ** <tr><td>INSERT <td>DELETE <td>
10830: ** The existing INSERT is removed from the changegroup. The DELETE is
10831: ** not added.
10832: ** <tr><td>UPDATE <td>INSERT <td>
10833: ** The new change is ignored. This case does not occur if the new
10834: ** changeset was recorded immediately after the changesets already
10835: ** added to the changegroup.
10836: ** <tr><td>UPDATE <td>UPDATE <td>
1.4.2.3 ! misho 10837: ** The existing UPDATE remains within the changegroup. It is amended
! 10838: ** so that the accompanying values are as if the row was updated once
1.4 misho 10839: ** by the existing change and then again by the new change.
10840: ** <tr><td>UPDATE <td>DELETE <td>
10841: ** The existing UPDATE is replaced by the new DELETE within the
10842: ** changegroup.
10843: ** <tr><td>DELETE <td>INSERT <td>
10844: ** If one or more of the column values in the row inserted by the
1.4.2.3 ! misho 10845: ** new change differ from those in the row deleted by the existing
1.4 misho 10846: ** change, the existing DELETE is replaced by an UPDATE within the
1.4.2.3 ! misho 10847: ** changegroup. Otherwise, if the inserted row is exactly the same
1.4 misho 10848: ** as the deleted row, the existing DELETE is simply discarded.
10849: ** <tr><td>DELETE <td>UPDATE <td>
10850: ** The new change is ignored. This case does not occur if the new
10851: ** changeset was recorded immediately after the changesets already
10852: ** added to the changegroup.
10853: ** <tr><td>DELETE <td>DELETE <td>
10854: ** The new change is ignored. This case does not occur if the new
10855: ** changeset was recorded immediately after the changesets already
10856: ** added to the changegroup.
10857: ** </table>
10858: **
10859: ** If the new changeset contains changes to a table that is already present
10860: ** in the changegroup, then the number of columns and the position of the
10861: ** primary key columns for the table must be consistent. If this is not the
10862: ** case, this function fails with SQLITE_SCHEMA. If the input changeset
10863: ** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is
10864: ** returned. Or, if an out-of-memory condition occurs during processing, this
1.4.2.3 ! misho 10865: ** function returns SQLITE_NOMEM. In all cases, if an error occurs the state
! 10866: ** of the final contents of the changegroup is undefined.
1.4 misho 10867: **
10868: ** If no error occurs, SQLITE_OK is returned.
10869: */
1.4.2.1 misho 10870: SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData);
1.4 misho 10871:
10872: /*
1.4.2.1 misho 10873: ** CAPI3REF: Obtain A Composite Changeset From A Changegroup
1.4.2.2 misho 10874: ** METHOD: sqlite3_changegroup
1.4.2.1 misho 10875: **
1.4 misho 10876: ** Obtain a buffer containing a changeset (or patchset) representing the
10877: ** current contents of the changegroup. If the inputs to the changegroup
10878: ** were themselves changesets, the output is a changeset. Or, if the
10879: ** inputs were patchsets, the output is also a patchset.
10880: **
10881: ** As with the output of the sqlite3session_changeset() and
10882: ** sqlite3session_patchset() functions, all changes related to a single
10883: ** table are grouped together in the output of this function. Tables appear
10884: ** in the same order as for the very first changeset added to the changegroup.
10885: ** If the second or subsequent changesets added to the changegroup contain
10886: ** changes for tables that do not appear in the first changeset, they are
10887: ** appended onto the end of the output changeset, again in the order in
10888: ** which they are first encountered.
10889: **
10890: ** If an error occurs, an SQLite error code is returned and the output
10891: ** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK
1.4.2.3 ! misho 10892: ** is returned and the output variables are set to the size of and a
1.4 misho 10893: ** pointer to the output buffer, respectively. In this case it is the
10894: ** responsibility of the caller to eventually free the buffer using a
10895: ** call to sqlite3_free().
10896: */
1.4.2.1 misho 10897: SQLITE_API int sqlite3changegroup_output(
1.4 misho 10898: sqlite3_changegroup*,
10899: int *pnData, /* OUT: Size of output buffer in bytes */
10900: void **ppData /* OUT: Pointer to output buffer */
10901: );
10902:
10903: /*
1.4.2.1 misho 10904: ** CAPI3REF: Delete A Changegroup Object
1.4.2.2 misho 10905: ** DESTRUCTOR: sqlite3_changegroup
1.4 misho 10906: */
1.4.2.1 misho 10907: SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*);
1.4 misho 10908:
10909: /*
10910: ** CAPI3REF: Apply A Changeset To A Database
10911: **
1.4.2.2 misho 10912: ** Apply a changeset or patchset to a database. These functions attempt to
10913: ** update the "main" database attached to handle db with the changes found in
1.4.2.3 ! misho 10914: ** the changeset passed via the second and third arguments.
1.4 misho 10915: **
1.4.2.2 misho 10916: ** The fourth argument (xFilter) passed to these functions is the "filter
1.4 misho 10917: ** callback". If it is not NULL, then for each table affected by at least one
10918: ** change in the changeset, the filter callback is invoked with
10919: ** the table name as the second argument, and a copy of the context pointer
1.4.2.2 misho 10920: ** passed as the sixth argument as the first. If the "filter callback"
10921: ** returns zero, then no attempt is made to apply any changes to the table.
10922: ** Otherwise, if the return value is non-zero or the xFilter argument to
10923: ** is NULL, all changes related to the table are attempted.
1.4 misho 10924: **
1.4.2.3 ! misho 10925: ** For each table that is not excluded by the filter callback, this function
! 10926: ** tests that the target database contains a compatible table. A table is
1.4 misho 10927: ** considered compatible if all of the following are true:
10928: **
10929: ** <ul>
1.4.2.3 ! misho 10930: ** <li> The table has the same name as the name recorded in the
1.4 misho 10931: ** changeset, and
1.4.2.3 ! misho 10932: ** <li> The table has at least as many columns as recorded in the
1.4 misho 10933: ** changeset, and
1.4.2.3 ! misho 10934: ** <li> The table has primary key columns in the same position as
1.4 misho 10935: ** recorded in the changeset.
10936: ** </ul>
10937: **
10938: ** If there is no compatible table, it is not an error, but none of the
10939: ** changes associated with the table are applied. A warning message is issued
10940: ** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most
10941: ** one such warning is issued for each table in the changeset.
10942: **
1.4.2.3 ! misho 10943: ** For each change for which there is a compatible table, an attempt is made
! 10944: ** to modify the table contents according to the UPDATE, INSERT or DELETE
! 10945: ** change. If a change cannot be applied cleanly, the conflict handler
! 10946: ** function passed as the fifth argument to sqlite3changeset_apply() may be
! 10947: ** invoked. A description of exactly when the conflict handler is invoked for
1.4 misho 10948: ** each type of change is below.
10949: **
10950: ** Unlike the xFilter argument, xConflict may not be passed NULL. The results
10951: ** of passing anything other than a valid function pointer as the xConflict
10952: ** argument are undefined.
10953: **
10954: ** Each time the conflict handler function is invoked, it must return one
1.4.2.3 ! misho 10955: ** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or
1.4 misho 10956: ** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned
10957: ** if the second argument passed to the conflict handler is either
10958: ** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler
10959: ** returns an illegal value, any changes already made are rolled back and
1.4.2.3 ! misho 10960: ** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different
1.4 misho 10961: ** actions are taken by sqlite3changeset_apply() depending on the value
10962: ** returned by each invocation of the conflict-handler function. Refer to
1.4.2.3 ! misho 10963: ** the documentation for the three
1.4 misho 10964: ** [SQLITE_CHANGESET_OMIT|available return values] for details.
10965: **
10966: ** <dl>
10967: ** <dt>DELETE Changes<dd>
1.4.2.3 ! misho 10968: ** For each DELETE change, the function checks if the target database
! 10969: ** contains a row with the same primary key value (or values) as the
! 10970: ** original row values stored in the changeset. If it does, and the values
! 10971: ** stored in all non-primary key columns also match the values stored in
1.4 misho 10972: ** the changeset the row is deleted from the target database.
10973: **
10974: ** If a row with matching primary key values is found, but one or more of
10975: ** the non-primary key fields contains a value different from the original
10976: ** row value stored in the changeset, the conflict-handler function is
1.4.2.1 misho 10977: ** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the
10978: ** database table has more columns than are recorded in the changeset,
10979: ** only the values of those non-primary key fields are compared against
10980: ** the current database contents - any trailing database table columns
10981: ** are ignored.
1.4 misho 10982: **
10983: ** If no row with matching primary key values is found in the database,
10984: ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
10985: ** passed as the second argument.
10986: **
10987: ** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT
10988: ** (which can only happen if a foreign key constraint is violated), the
10989: ** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT]
10990: ** passed as the second argument. This includes the case where the DELETE
10991: ** operation is attempted because an earlier call to the conflict handler
10992: ** function returned [SQLITE_CHANGESET_REPLACE].
10993: **
10994: ** <dt>INSERT Changes<dd>
10995: ** For each INSERT change, an attempt is made to insert the new row into
1.4.2.1 misho 10996: ** the database. If the changeset row contains fewer fields than the
10997: ** database table, the trailing fields are populated with their default
10998: ** values.
1.4 misho 10999: **
1.4.2.3 ! misho 11000: ** If the attempt to insert the row fails because the database already
1.4 misho 11001: ** contains a row with the same primary key values, the conflict handler
1.4.2.3 ! misho 11002: ** function is invoked with the second argument set to
1.4 misho 11003: ** [SQLITE_CHANGESET_CONFLICT].
11004: **
11005: ** If the attempt to insert the row fails because of some other constraint
1.4.2.3 ! misho 11006: ** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is
1.4 misho 11007: ** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT].
1.4.2.3 ! misho 11008: ** This includes the case where the INSERT operation is re-attempted because
! 11009: ** an earlier call to the conflict handler function returned
1.4 misho 11010: ** [SQLITE_CHANGESET_REPLACE].
11011: **
11012: ** <dt>UPDATE Changes<dd>
1.4.2.3 ! misho 11013: ** For each UPDATE change, the function checks if the target database
! 11014: ** contains a row with the same primary key value (or values) as the
! 11015: ** original row values stored in the changeset. If it does, and the values
1.4.2.1 misho 11016: ** stored in all modified non-primary key columns also match the values
11017: ** stored in the changeset the row is updated within the target database.
1.4 misho 11018: **
11019: ** If a row with matching primary key values is found, but one or more of
1.4.2.1 misho 11020: ** the modified non-primary key fields contains a value different from an
11021: ** original row value stored in the changeset, the conflict-handler function
11022: ** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since
1.4 misho 11023: ** UPDATE changes only contain values for non-primary key fields that are
11024: ** to be modified, only those fields need to match the original values to
11025: ** avoid the SQLITE_CHANGESET_DATA conflict-handler callback.
11026: **
11027: ** If no row with matching primary key values is found in the database,
11028: ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
11029: ** passed as the second argument.
11030: **
1.4.2.3 ! misho 11031: ** If the UPDATE operation is attempted, but SQLite returns
! 11032: ** SQLITE_CONSTRAINT, the conflict-handler function is invoked with
1.4 misho 11033: ** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument.
1.4.2.3 ! misho 11034: ** This includes the case where the UPDATE operation is attempted after
1.4 misho 11035: ** an earlier call to the conflict handler function returned
1.4.2.3 ! misho 11036: ** [SQLITE_CHANGESET_REPLACE].
1.4 misho 11037: ** </dl>
11038: **
11039: ** It is safe to execute SQL statements, including those that write to the
11040: ** table that the callback related to, from within the xConflict callback.
1.4.2.3 ! misho 11041: ** This can be used to further customize the application's conflict
1.4 misho 11042: ** resolution strategy.
11043: **
1.4.2.2 misho 11044: ** All changes made by these functions are enclosed in a savepoint transaction.
1.4 misho 11045: ** If any other error (aside from a constraint failure when attempting to
11046: ** write to the target database) occurs, then the savepoint transaction is
1.4.2.3 ! misho 11047: ** rolled back, restoring the target database to its original state, and an
1.4 misho 11048: ** SQLite error code returned.
1.4.2.2 misho 11049: **
11050: ** If the output parameters (ppRebase) and (pnRebase) are non-NULL and
11051: ** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2()
1.4.2.3 ! misho 11052: ** may set (*ppRebase) to point to a "rebase" that may be used with the
1.4.2.2 misho 11053: ** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase)
11054: ** is set to the size of the buffer in bytes. It is the responsibility of the
11055: ** caller to eventually free any such buffer using sqlite3_free(). The buffer
11056: ** is only allocated and populated if one or more conflicts were encountered
11057: ** while applying the patchset. See comments surrounding the sqlite3_rebaser
11058: ** APIs for further details.
11059: **
11060: ** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent
11061: ** may be modified by passing a combination of
11062: ** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter.
11063: **
11064: ** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b>
11065: ** and therefore subject to change.
1.4 misho 11066: */
1.4.2.1 misho 11067: SQLITE_API int sqlite3changeset_apply(
1.4 misho 11068: sqlite3 *db, /* Apply change to "main" db of this handle */
11069: int nChangeset, /* Size of changeset in bytes */
11070: void *pChangeset, /* Changeset blob */
11071: int(*xFilter)(
11072: void *pCtx, /* Copy of sixth arg to _apply() */
11073: const char *zTab /* Table name */
11074: ),
11075: int(*xConflict)(
11076: void *pCtx, /* Copy of sixth arg to _apply() */
11077: int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
11078: sqlite3_changeset_iter *p /* Handle describing change and conflict */
11079: ),
11080: void *pCtx /* First argument passed to xConflict */
11081: );
1.4.2.2 misho 11082: SQLITE_API int sqlite3changeset_apply_v2(
11083: sqlite3 *db, /* Apply change to "main" db of this handle */
11084: int nChangeset, /* Size of changeset in bytes */
11085: void *pChangeset, /* Changeset blob */
11086: int(*xFilter)(
11087: void *pCtx, /* Copy of sixth arg to _apply() */
11088: const char *zTab /* Table name */
11089: ),
11090: int(*xConflict)(
11091: void *pCtx, /* Copy of sixth arg to _apply() */
11092: int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
11093: sqlite3_changeset_iter *p /* Handle describing change and conflict */
11094: ),
11095: void *pCtx, /* First argument passed to xConflict */
11096: void **ppRebase, int *pnRebase, /* OUT: Rebase data */
11097: int flags /* SESSION_CHANGESETAPPLY_* flags */
11098: );
11099:
11100: /*
11101: ** CAPI3REF: Flags for sqlite3changeset_apply_v2
11102: **
11103: ** The following flags may passed via the 9th parameter to
11104: ** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]:
11105: **
11106: ** <dl>
11107: ** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd>
11108: ** Usually, the sessions module encloses all operations performed by
11109: ** a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The
11110: ** SAVEPOINT is committed if the changeset or patchset is successfully
11111: ** applied, or rolled back if an error occurs. Specifying this flag
11112: ** causes the sessions module to omit this savepoint. In this case, if the
1.4.2.3 ! misho 11113: ** caller has an open transaction or savepoint when apply_v2() is called,
1.4.2.2 misho 11114: ** it may revert the partially applied changeset by rolling it back.
11115: **
11116: ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd>
11117: ** Invert the changeset before applying it. This is equivalent to inverting
11118: ** a changeset using sqlite3changeset_invert() before applying it. It is
11119: ** an error to specify this flag with a patchset.
11120: */
11121: #define SQLITE_CHANGESETAPPLY_NOSAVEPOINT 0x0001
11122: #define SQLITE_CHANGESETAPPLY_INVERT 0x0002
1.4 misho 11123:
1.4.2.3 ! misho 11124: /*
1.4 misho 11125: ** CAPI3REF: Constants Passed To The Conflict Handler
11126: **
11127: ** Values that may be passed as the second argument to a conflict-handler.
11128: **
11129: ** <dl>
11130: ** <dt>SQLITE_CHANGESET_DATA<dd>
11131: ** The conflict handler is invoked with CHANGESET_DATA as the second argument
11132: ** when processing a DELETE or UPDATE change if a row with the required
1.4.2.3 ! misho 11133: ** PRIMARY KEY fields is present in the database, but one or more other
! 11134: ** (non primary-key) fields modified by the update do not contain the
1.4 misho 11135: ** expected "before" values.
1.4.2.3 ! misho 11136: **
1.4 misho 11137: ** The conflicting row, in this case, is the database row with the matching
11138: ** primary key.
1.4.2.3 ! misho 11139: **
1.4 misho 11140: ** <dt>SQLITE_CHANGESET_NOTFOUND<dd>
11141: ** The conflict handler is invoked with CHANGESET_NOTFOUND as the second
11142: ** argument when processing a DELETE or UPDATE change if a row with the
11143: ** required PRIMARY KEY fields is not present in the database.
1.4.2.3 ! misho 11144: **
1.4 misho 11145: ** There is no conflicting row in this case. The results of invoking the
11146: ** sqlite3changeset_conflict() API are undefined.
1.4.2.3 ! misho 11147: **
1.4 misho 11148: ** <dt>SQLITE_CHANGESET_CONFLICT<dd>
11149: ** CHANGESET_CONFLICT is passed as the second argument to the conflict
1.4.2.3 ! misho 11150: ** handler while processing an INSERT change if the operation would result
1.4 misho 11151: ** in duplicate primary key values.
1.4.2.3 ! misho 11152: **
1.4 misho 11153: ** The conflicting row in this case is the database row with the matching
11154: ** primary key.
11155: **
11156: ** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd>
11157: ** If foreign key handling is enabled, and applying a changeset leaves the
1.4.2.3 ! misho 11158: ** database in a state containing foreign key violations, the conflict
1.4 misho 11159: ** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument
11160: ** exactly once before the changeset is committed. If the conflict handler
11161: ** returns CHANGESET_OMIT, the changes, including those that caused the
11162: ** foreign key constraint violation, are committed. Or, if it returns
11163: ** CHANGESET_ABORT, the changeset is rolled back.
11164: **
11165: ** No current or conflicting row information is provided. The only function
11166: ** it is possible to call on the supplied sqlite3_changeset_iter handle
11167: ** is sqlite3changeset_fk_conflicts().
1.4.2.3 ! misho 11168: **
1.4 misho 11169: ** <dt>SQLITE_CHANGESET_CONSTRAINT<dd>
1.4.2.3 ! misho 11170: ** If any other constraint violation occurs while applying a change (i.e.
! 11171: ** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is
1.4 misho 11172: ** invoked with CHANGESET_CONSTRAINT as the second argument.
1.4.2.3 ! misho 11173: **
1.4 misho 11174: ** There is no conflicting row in this case. The results of invoking the
11175: ** sqlite3changeset_conflict() API are undefined.
11176: **
11177: ** </dl>
11178: */
11179: #define SQLITE_CHANGESET_DATA 1
11180: #define SQLITE_CHANGESET_NOTFOUND 2
11181: #define SQLITE_CHANGESET_CONFLICT 3
11182: #define SQLITE_CHANGESET_CONSTRAINT 4
11183: #define SQLITE_CHANGESET_FOREIGN_KEY 5
11184:
1.4.2.3 ! misho 11185: /*
1.4 misho 11186: ** CAPI3REF: Constants Returned By The Conflict Handler
11187: **
11188: ** A conflict handler callback must return one of the following three values.
11189: **
11190: ** <dl>
11191: ** <dt>SQLITE_CHANGESET_OMIT<dd>
11192: ** If a conflict handler returns this value no special action is taken. The
1.4.2.3 ! misho 11193: ** change that caused the conflict is not applied. The session module
1.4 misho 11194: ** continues to the next change in the changeset.
11195: **
11196: ** <dt>SQLITE_CHANGESET_REPLACE<dd>
11197: ** This value may only be returned if the second argument to the conflict
11198: ** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this
1.4.2.3 ! misho 11199: ** is not the case, any changes applied so far are rolled back and the
1.4 misho 11200: ** call to sqlite3changeset_apply() returns SQLITE_MISUSE.
11201: **
11202: ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict
11203: ** handler, then the conflicting row is either updated or deleted, depending
11204: ** on the type of change.
11205: **
11206: ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict
11207: ** handler, then the conflicting row is removed from the database and a
11208: ** second attempt to apply the change is made. If this second attempt fails,
11209: ** the original row is restored to the database before continuing.
11210: **
11211: ** <dt>SQLITE_CHANGESET_ABORT<dd>
1.4.2.3 ! misho 11212: ** If this value is returned, any changes applied so far are rolled back
1.4 misho 11213: ** and the call to sqlite3changeset_apply() returns SQLITE_ABORT.
11214: ** </dl>
11215: */
11216: #define SQLITE_CHANGESET_OMIT 0
11217: #define SQLITE_CHANGESET_REPLACE 1
11218: #define SQLITE_CHANGESET_ABORT 2
11219:
1.4.2.3 ! misho 11220: /*
1.4.2.2 misho 11221: ** CAPI3REF: Rebasing changesets
11222: ** EXPERIMENTAL
11223: **
11224: ** Suppose there is a site hosting a database in state S0. And that
11225: ** modifications are made that move that database to state S1 and a
11226: ** changeset recorded (the "local" changeset). Then, a changeset based
1.4.2.3 ! misho 11227: ** on S0 is received from another site (the "remote" changeset) and
! 11228: ** applied to the database. The database is then in state
1.4.2.2 misho 11229: ** (S1+"remote"), where the exact state depends on any conflict
11230: ** resolution decisions (OMIT or REPLACE) made while applying "remote".
1.4.2.3 ! misho 11231: ** Rebasing a changeset is to update it to take those conflict
1.4.2.2 misho 11232: ** resolution decisions into account, so that the same conflicts
1.4.2.3 ! misho 11233: ** do not have to be resolved elsewhere in the network.
1.4.2.2 misho 11234: **
11235: ** For example, if both the local and remote changesets contain an
11236: ** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)":
11237: **
11238: ** local: INSERT INTO t1 VALUES(1, 'v1');
11239: ** remote: INSERT INTO t1 VALUES(1, 'v2');
11240: **
11241: ** and the conflict resolution is REPLACE, then the INSERT change is
11242: ** removed from the local changeset (it was overridden). Or, if the
11243: ** conflict resolution was "OMIT", then the local changeset is modified
11244: ** to instead contain:
11245: **
11246: ** UPDATE t1 SET b = 'v2' WHERE a=1;
11247: **
11248: ** Changes within the local changeset are rebased as follows:
11249: **
11250: ** <dl>
11251: ** <dt>Local INSERT<dd>
1.4.2.3 ! misho 11252: ** This may only conflict with a remote INSERT. If the conflict
1.4.2.2 misho 11253: ** resolution was OMIT, then add an UPDATE change to the rebased
11254: ** changeset. Or, if the conflict resolution was REPLACE, add
11255: ** nothing to the rebased changeset.
11256: **
11257: ** <dt>Local DELETE<dd>
11258: ** This may conflict with a remote UPDATE or DELETE. In both cases the
11259: ** only possible resolution is OMIT. If the remote operation was a
11260: ** DELETE, then add no change to the rebased changeset. If the remote
11261: ** operation was an UPDATE, then the old.* fields of change are updated
11262: ** to reflect the new.* values in the UPDATE.
11263: **
11264: ** <dt>Local UPDATE<dd>
11265: ** This may conflict with a remote UPDATE or DELETE. If it conflicts
11266: ** with a DELETE, and the conflict resolution was OMIT, then the update
11267: ** is changed into an INSERT. Any undefined values in the new.* record
11268: ** from the update change are filled in using the old.* values from
11269: ** the conflicting DELETE. Or, if the conflict resolution was REPLACE,
11270: ** the UPDATE change is simply omitted from the rebased changeset.
11271: **
11272: ** If conflict is with a remote UPDATE and the resolution is OMIT, then
11273: ** the old.* values are rebased using the new.* values in the remote
11274: ** change. Or, if the resolution is REPLACE, then the change is copied
11275: ** into the rebased changeset with updates to columns also updated by
1.4.2.3 ! misho 11276: ** the conflicting remote UPDATE removed. If this means no columns would
1.4.2.2 misho 11277: ** be updated, the change is omitted.
11278: ** </dl>
11279: **
1.4.2.3 ! misho 11280: ** A local change may be rebased against multiple remote changes
! 11281: ** simultaneously. If a single key is modified by multiple remote
1.4.2.2 misho 11282: ** changesets, they are combined as follows before the local changeset
11283: ** is rebased:
11284: **
11285: ** <ul>
11286: ** <li> If there has been one or more REPLACE resolutions on a
11287: ** key, it is rebased according to a REPLACE.
11288: **
11289: ** <li> If there have been no REPLACE resolutions on a key, then
11290: ** the local changeset is rebased according to the most recent
11291: ** of the OMIT resolutions.
11292: ** </ul>
11293: **
1.4.2.3 ! misho 11294: ** Note that conflict resolutions from multiple remote changesets are
! 11295: ** combined on a per-field basis, not per-row. This means that in the
! 11296: ** case of multiple remote UPDATE operations, some fields of a single
! 11297: ** local change may be rebased for REPLACE while others are rebased for
1.4.2.2 misho 11298: ** OMIT.
11299: **
11300: ** In order to rebase a local changeset, the remote changeset must first
11301: ** be applied to the local database using sqlite3changeset_apply_v2() and
11302: ** the buffer of rebase information captured. Then:
11303: **
11304: ** <ol>
1.4.2.3 ! misho 11305: ** <li> An sqlite3_rebaser object is created by calling
1.4.2.2 misho 11306: ** sqlite3rebaser_create().
11307: ** <li> The new object is configured with the rebase buffer obtained from
11308: ** sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure().
11309: ** If the local changeset is to be rebased against multiple remote
11310: ** changesets, then sqlite3rebaser_configure() should be called
11311: ** multiple times, in the same order that the multiple
11312: ** sqlite3changeset_apply_v2() calls were made.
11313: ** <li> Each local changeset is rebased by calling sqlite3rebaser_rebase().
11314: ** <li> The sqlite3_rebaser object is deleted by calling
11315: ** sqlite3rebaser_delete().
11316: ** </ol>
11317: */
11318: typedef struct sqlite3_rebaser sqlite3_rebaser;
11319:
11320: /*
11321: ** CAPI3REF: Create a changeset rebaser object.
11322: ** EXPERIMENTAL
11323: **
11324: ** Allocate a new changeset rebaser object. If successful, set (*ppNew) to
11325: ** point to the new object and return SQLITE_OK. Otherwise, if an error
1.4.2.3 ! misho 11326: ** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew)
! 11327: ** to NULL.
1.4.2.2 misho 11328: */
11329: SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew);
11330:
11331: /*
11332: ** CAPI3REF: Configure a changeset rebaser object.
11333: ** EXPERIMENTAL
11334: **
11335: ** Configure the changeset rebaser object to rebase changesets according
11336: ** to the conflict resolutions described by buffer pRebase (size nRebase
11337: ** bytes), which must have been obtained from a previous call to
11338: ** sqlite3changeset_apply_v2().
11339: */
11340: SQLITE_API int sqlite3rebaser_configure(
1.4.2.3 ! misho 11341: sqlite3_rebaser*,
1.4.2.2 misho 11342: int nRebase, const void *pRebase
1.4.2.3 ! misho 11343: );
1.4.2.2 misho 11344:
11345: /*
11346: ** CAPI3REF: Rebase a changeset
11347: ** EXPERIMENTAL
11348: **
11349: ** Argument pIn must point to a buffer containing a changeset nIn bytes
11350: ** in size. This function allocates and populates a buffer with a copy
1.4.2.3 ! misho 11351: ** of the changeset rebased according to the configuration of the
1.4.2.2 misho 11352: ** rebaser object passed as the first argument. If successful, (*ppOut)
1.4.2.3 ! misho 11353: ** is set to point to the new buffer containing the rebased changeset and
1.4.2.2 misho 11354: ** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the
11355: ** responsibility of the caller to eventually free the new buffer using
11356: ** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut)
11357: ** are set to zero and an SQLite error code returned.
11358: */
11359: SQLITE_API int sqlite3rebaser_rebase(
11360: sqlite3_rebaser*,
1.4.2.3 ! misho 11361: int nIn, const void *pIn,
! 11362: int *pnOut, void **ppOut
1.4.2.2 misho 11363: );
11364:
11365: /*
11366: ** CAPI3REF: Delete a changeset rebaser object.
11367: ** EXPERIMENTAL
11368: **
11369: ** Delete the changeset rebaser object and all associated resources. There
11370: ** should be one call to this function for each successful invocation
11371: ** of sqlite3rebaser_create().
11372: */
1.4.2.3 ! misho 11373: SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p);
1.4.2.2 misho 11374:
1.4 misho 11375: /*
11376: ** CAPI3REF: Streaming Versions of API functions.
11377: **
1.4.2.3 ! misho 11378: ** The six streaming API xxx_strm() functions serve similar purposes to the
1.4 misho 11379: ** corresponding non-streaming API functions:
11380: **
11381: ** <table border=1 style="margin-left:8ex;margin-right:8ex">
11382: ** <tr><th>Streaming function<th>Non-streaming equivalent</th>
1.4.2.3 ! misho 11383: ** <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply]
! 11384: ** <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2]
! 11385: ** <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat]
! 11386: ** <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert]
! 11387: ** <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start]
! 11388: ** <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset]
! 11389: ** <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset]
1.4 misho 11390: ** </table>
11391: **
11392: ** Non-streaming functions that accept changesets (or patchsets) as input
1.4.2.3 ! misho 11393: ** require that the entire changeset be stored in a single buffer in memory.
! 11394: ** Similarly, those that return a changeset or patchset do so by returning
! 11395: ** a pointer to a single large buffer allocated using sqlite3_malloc().
! 11396: ** Normally this is convenient. However, if an application running in a
1.4 misho 11397: ** low-memory environment is required to handle very large changesets, the
11398: ** large contiguous memory allocations required can become onerous.
11399: **
11400: ** In order to avoid this problem, instead of a single large buffer, input
11401: ** is passed to a streaming API functions by way of a callback function that
11402: ** the sessions module invokes to incrementally request input data as it is
11403: ** required. In all cases, a pair of API function parameters such as
11404: **
11405: ** <pre>
11406: ** int nChangeset,
11407: ** void *pChangeset,
11408: ** </pre>
11409: **
11410: ** Is replaced by:
11411: **
11412: ** <pre>
11413: ** int (*xInput)(void *pIn, void *pData, int *pnData),
11414: ** void *pIn,
11415: ** </pre>
11416: **
11417: ** Each time the xInput callback is invoked by the sessions module, the first
1.4.2.3 ! misho 11418: ** argument passed is a copy of the supplied pIn context pointer. The second
! 11419: ** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no
! 11420: ** error occurs the xInput method should copy up to (*pnData) bytes of data
! 11421: ** into the buffer and set (*pnData) to the actual number of bytes copied
! 11422: ** before returning SQLITE_OK. If the input is completely exhausted, (*pnData)
! 11423: ** should be set to zero to indicate this. Or, if an error occurs, an SQLite
1.4 misho 11424: ** error code should be returned. In all cases, if an xInput callback returns
11425: ** an error, all processing is abandoned and the streaming API function
11426: ** returns a copy of the error code to the caller.
11427: **
11428: ** In the case of sqlite3changeset_start_strm(), the xInput callback may be
11429: ** invoked by the sessions module at any point during the lifetime of the
11430: ** iterator. If such an xInput callback returns an error, the iterator enters
1.4.2.3 ! misho 11431: ** an error state, whereby all subsequent calls to iterator functions
1.4 misho 11432: ** immediately fail with the same error code as returned by xInput.
11433: **
11434: ** Similarly, streaming API functions that return changesets (or patchsets)
11435: ** return them in chunks by way of a callback function instead of via a
11436: ** pointer to a single large buffer. In this case, a pair of parameters such
11437: ** as:
11438: **
11439: ** <pre>
11440: ** int *pnChangeset,
11441: ** void **ppChangeset,
11442: ** </pre>
11443: **
11444: ** Is replaced by:
11445: **
11446: ** <pre>
11447: ** int (*xOutput)(void *pOut, const void *pData, int nData),
11448: ** void *pOut
11449: ** </pre>
11450: **
11451: ** The xOutput callback is invoked zero or more times to return data to
11452: ** the application. The first parameter passed to each call is a copy of the
11453: ** pOut pointer supplied by the application. The second parameter, pData,
11454: ** points to a buffer nData bytes in size containing the chunk of output
11455: ** data being returned. If the xOutput callback successfully processes the
11456: ** supplied data, it should return SQLITE_OK to indicate success. Otherwise,
11457: ** it should return some other SQLite error code. In this case processing
11458: ** is immediately abandoned and the streaming API function returns a copy
11459: ** of the xOutput error code to the application.
11460: **
1.4.2.3 ! misho 11461: ** The sessions module never invokes an xOutput callback with the third
1.4 misho 11462: ** parameter set to a value less than or equal to zero. Other than this,
11463: ** no guarantees are made as to the size of the chunks of data returned.
11464: */
1.4.2.1 misho 11465: SQLITE_API int sqlite3changeset_apply_strm(
1.4 misho 11466: sqlite3 *db, /* Apply change to "main" db of this handle */
11467: int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
11468: void *pIn, /* First arg for xInput */
11469: int(*xFilter)(
11470: void *pCtx, /* Copy of sixth arg to _apply() */
11471: const char *zTab /* Table name */
11472: ),
11473: int(*xConflict)(
11474: void *pCtx, /* Copy of sixth arg to _apply() */
11475: int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
11476: sqlite3_changeset_iter *p /* Handle describing change and conflict */
11477: ),
11478: void *pCtx /* First argument passed to xConflict */
11479: );
1.4.2.2 misho 11480: SQLITE_API int sqlite3changeset_apply_v2_strm(
11481: sqlite3 *db, /* Apply change to "main" db of this handle */
11482: int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
11483: void *pIn, /* First arg for xInput */
11484: int(*xFilter)(
11485: void *pCtx, /* Copy of sixth arg to _apply() */
11486: const char *zTab /* Table name */
11487: ),
11488: int(*xConflict)(
11489: void *pCtx, /* Copy of sixth arg to _apply() */
11490: int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
11491: sqlite3_changeset_iter *p /* Handle describing change and conflict */
11492: ),
11493: void *pCtx, /* First argument passed to xConflict */
11494: void **ppRebase, int *pnRebase,
11495: int flags
11496: );
1.4.2.1 misho 11497: SQLITE_API int sqlite3changeset_concat_strm(
1.4 misho 11498: int (*xInputA)(void *pIn, void *pData, int *pnData),
11499: void *pInA,
11500: int (*xInputB)(void *pIn, void *pData, int *pnData),
11501: void *pInB,
11502: int (*xOutput)(void *pOut, const void *pData, int nData),
11503: void *pOut
11504: );
1.4.2.1 misho 11505: SQLITE_API int sqlite3changeset_invert_strm(
1.4 misho 11506: int (*xInput)(void *pIn, void *pData, int *pnData),
11507: void *pIn,
11508: int (*xOutput)(void *pOut, const void *pData, int nData),
11509: void *pOut
11510: );
1.4.2.1 misho 11511: SQLITE_API int sqlite3changeset_start_strm(
1.4 misho 11512: sqlite3_changeset_iter **pp,
11513: int (*xInput)(void *pIn, void *pData, int *pnData),
11514: void *pIn
11515: );
1.4.2.2 misho 11516: SQLITE_API int sqlite3changeset_start_v2_strm(
11517: sqlite3_changeset_iter **pp,
11518: int (*xInput)(void *pIn, void *pData, int *pnData),
11519: void *pIn,
11520: int flags
11521: );
1.4.2.1 misho 11522: SQLITE_API int sqlite3session_changeset_strm(
1.4 misho 11523: sqlite3_session *pSession,
11524: int (*xOutput)(void *pOut, const void *pData, int nData),
11525: void *pOut
11526: );
1.4.2.1 misho 11527: SQLITE_API int sqlite3session_patchset_strm(
1.4 misho 11528: sqlite3_session *pSession,
11529: int (*xOutput)(void *pOut, const void *pData, int nData),
11530: void *pOut
11531: );
1.4.2.3 ! misho 11532: SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*,
1.4 misho 11533: int (*xInput)(void *pIn, void *pData, int *pnData),
11534: void *pIn
11535: );
1.4.2.1 misho 11536: SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*,
1.4.2.3 ! misho 11537: int (*xOutput)(void *pOut, const void *pData, int nData),
1.4 misho 11538: void *pOut
11539: );
1.4.2.2 misho 11540: SQLITE_API int sqlite3rebaser_rebase_strm(
11541: sqlite3_rebaser *pRebaser,
11542: int (*xInput)(void *pIn, void *pData, int *pnData),
11543: void *pIn,
11544: int (*xOutput)(void *pOut, const void *pData, int nData),
11545: void *pOut
11546: );
11547:
11548: /*
11549: ** CAPI3REF: Configure global parameters
11550: **
11551: ** The sqlite3session_config() interface is used to make global configuration
1.4.2.3 ! misho 11552: ** changes to the sessions module in order to tune it to the specific needs
1.4.2.2 misho 11553: ** of the application.
11554: **
11555: ** The sqlite3session_config() interface is not threadsafe. If it is invoked
11556: ** while any other thread is inside any other sessions method then the
11557: ** results are undefined. Furthermore, if it is invoked after any sessions
1.4.2.3 ! misho 11558: ** related objects have been created, the results are also undefined.
1.4.2.2 misho 11559: **
11560: ** The first argument to the sqlite3session_config() function must be one
1.4.2.3 ! misho 11561: ** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The
1.4.2.2 misho 11562: ** interpretation of the (void*) value passed as the second parameter and
11563: ** the effect of calling this function depends on the value of the first
11564: ** parameter.
11565: **
11566: ** <dl>
11567: ** <dt>SQLITE_SESSION_CONFIG_STRMSIZE<dd>
11568: ** By default, the sessions module streaming interfaces attempt to input
11569: ** and output data in approximately 1 KiB chunks. This operand may be used
11570: ** to set and query the value of this configuration setting. The pointer
11571: ** passed as the second argument must point to a value of type (int).
11572: ** If this value is greater than 0, it is used as the new streaming data
11573: ** chunk size for both input and output. Before returning, the (int) value
11574: ** pointed to by pArg is set to the final value of the streaming interface
11575: ** chunk size.
11576: ** </dl>
11577: **
11578: ** This function returns SQLITE_OK if successful, or an SQLite error code
11579: ** otherwise.
11580: */
11581: SQLITE_API int sqlite3session_config(int op, void *pArg);
1.4 misho 11582:
1.4.2.2 misho 11583: /*
11584: ** CAPI3REF: Values for sqlite3session_config().
11585: */
11586: #define SQLITE_SESSION_CONFIG_STRMSIZE 1
1.4 misho 11587:
11588: /*
11589: ** Make sure we can call this stuff from C++.
11590: */
11591: #ifdef __cplusplus
11592: }
11593: #endif
11594:
11595: #endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */
11596:
11597: /******** End of sqlite3session.h *********/
11598: /******** Begin file fts5.h *********/
11599: /*
11600: ** 2014 May 31
11601: **
11602: ** The author disclaims copyright to this source code. In place of
11603: ** a legal notice, here is a blessing:
11604: **
11605: ** May you do good and not evil.
11606: ** May you find forgiveness for yourself and forgive others.
11607: ** May you share freely, never taking more than you give.
11608: **
11609: ******************************************************************************
11610: **
1.4.2.3 ! misho 11611: ** Interfaces to extend FTS5. Using the interfaces defined in this file,
1.4 misho 11612: ** FTS5 may be extended with:
11613: **
11614: ** * custom tokenizers, and
11615: ** * custom auxiliary functions.
11616: */
11617:
11618:
11619: #ifndef _FTS5_H
11620: #define _FTS5_H
11621:
11622:
11623: #ifdef __cplusplus
11624: extern "C" {
11625: #endif
11626:
11627: /*************************************************************************
11628: ** CUSTOM AUXILIARY FUNCTIONS
11629: **
11630: ** Virtual table implementations may overload SQL functions by implementing
11631: ** the sqlite3_module.xFindFunction() method.
11632: */
11633:
11634: typedef struct Fts5ExtensionApi Fts5ExtensionApi;
11635: typedef struct Fts5Context Fts5Context;
11636: typedef struct Fts5PhraseIter Fts5PhraseIter;
11637:
11638: typedef void (*fts5_extension_function)(
11639: const Fts5ExtensionApi *pApi, /* API offered by current FTS version */
11640: Fts5Context *pFts, /* First arg to pass to pApi functions */
11641: sqlite3_context *pCtx, /* Context for returning result/error */
11642: int nVal, /* Number of values in apVal[] array */
11643: sqlite3_value **apVal /* Array of trailing arguments */
11644: );
11645:
11646: struct Fts5PhraseIter {
11647: const unsigned char *a;
11648: const unsigned char *b;
11649: };
11650:
11651: /*
11652: ** EXTENSION API FUNCTIONS
11653: **
11654: ** xUserData(pFts):
1.4.2.3 ! misho 11655: ** Return a copy of the context pointer the extension function was
1.4 misho 11656: ** registered with.
11657: **
11658: ** xColumnTotalSize(pFts, iCol, pnToken):
11659: ** If parameter iCol is less than zero, set output variable *pnToken
11660: ** to the total number of tokens in the FTS5 table. Or, if iCol is
11661: ** non-negative but less than the number of columns in the table, return
1.4.2.3 ! misho 11662: ** the total number of tokens in column iCol, considering all rows in
1.4 misho 11663: ** the FTS5 table.
11664: **
11665: ** If parameter iCol is greater than or equal to the number of columns
11666: ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
1.4.2.3 ! misho 11667: ** an OOM condition or IO error), an appropriate SQLite error code is
1.4 misho 11668: ** returned.
11669: **
11670: ** xColumnCount(pFts):
11671: ** Return the number of columns in the table.
11672: **
11673: ** xColumnSize(pFts, iCol, pnToken):
11674: ** If parameter iCol is less than zero, set output variable *pnToken
11675: ** to the total number of tokens in the current row. Or, if iCol is
11676: ** non-negative but less than the number of columns in the table, set
11677: ** *pnToken to the number of tokens in column iCol of the current row.
11678: **
11679: ** If parameter iCol is greater than or equal to the number of columns
11680: ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
1.4.2.3 ! misho 11681: ** an OOM condition or IO error), an appropriate SQLite error code is
1.4 misho 11682: ** returned.
11683: **
11684: ** This function may be quite inefficient if used with an FTS5 table
11685: ** created with the "columnsize=0" option.
11686: **
11687: ** xColumnText:
11688: ** This function attempts to retrieve the text of column iCol of the
11689: ** current document. If successful, (*pz) is set to point to a buffer
11690: ** containing the text in utf-8 encoding, (*pn) is set to the size in bytes
11691: ** (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
11692: ** if an error occurs, an SQLite error code is returned and the final values
11693: ** of (*pz) and (*pn) are undefined.
11694: **
11695: ** xPhraseCount:
11696: ** Returns the number of phrases in the current query expression.
11697: **
11698: ** xPhraseSize:
11699: ** Returns the number of tokens in phrase iPhrase of the query. Phrases
11700: ** are numbered starting from zero.
11701: **
11702: ** xInstCount:
11703: ** Set *pnInst to the total number of occurrences of all phrases within
11704: ** the query within the current row. Return SQLITE_OK if successful, or
11705: ** an error code (i.e. SQLITE_NOMEM) if an error occurs.
11706: **
11707: ** This API can be quite slow if used with an FTS5 table created with the
1.4.2.3 ! misho 11708: ** "detail=none" or "detail=column" option. If the FTS5 table is created
! 11709: ** with either "detail=none" or "detail=column" and "content=" option
1.4 misho 11710: ** (i.e. if it is a contentless table), then this API always returns 0.
11711: **
11712: ** xInst:
11713: ** Query for the details of phrase match iIdx within the current row.
11714: ** Phrase matches are numbered starting from zero, so the iIdx argument
11715: ** should be greater than or equal to zero and smaller than the value
11716: ** output by xInstCount().
11717: **
11718: ** Usually, output parameter *piPhrase is set to the phrase number, *piCol
11719: ** to the column in which it occurs and *piOff the token offset of the
1.4.2.2 misho 11720: ** first token of the phrase. Returns SQLITE_OK if successful, or an error
11721: ** code (i.e. SQLITE_NOMEM) if an error occurs.
1.4 misho 11722: **
11723: ** This API can be quite slow if used with an FTS5 table created with the
1.4.2.3 ! misho 11724: ** "detail=none" or "detail=column" option.
1.4 misho 11725: **
11726: ** xRowid:
11727: ** Returns the rowid of the current row.
11728: **
11729: ** xTokenize:
11730: ** Tokenize text using the tokenizer belonging to the FTS5 table.
11731: **
11732: ** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):
11733: ** This API function is used to query the FTS table for phrase iPhrase
11734: ** of the current query. Specifically, a query equivalent to:
11735: **
11736: ** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid
11737: **
11738: ** with $p set to a phrase equivalent to the phrase iPhrase of the
11739: ** current query is executed. Any column filter that applies to
1.4.2.3 ! misho 11740: ** phrase iPhrase of the current query is included in $p. For each
! 11741: ** row visited, the callback function passed as the fourth argument
! 11742: ** is invoked. The context and API objects passed to the callback
1.4 misho 11743: ** function may be used to access the properties of each matched row.
1.4.2.3 ! misho 11744: ** Invoking Api.xUserData() returns a copy of the pointer passed as
1.4 misho 11745: ** the third argument to pUserData.
11746: **
11747: ** If the callback function returns any value other than SQLITE_OK, the
11748: ** query is abandoned and the xQueryPhrase function returns immediately.
11749: ** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
11750: ** Otherwise, the error code is propagated upwards.
11751: **
11752: ** If the query runs to completion without incident, SQLITE_OK is returned.
11753: ** Or, if some error occurs before the query completes or is aborted by
11754: ** the callback, an SQLite error code is returned.
11755: **
11756: **
11757: ** xSetAuxdata(pFts5, pAux, xDelete)
11758: **
1.4.2.3 ! misho 11759: ** Save the pointer passed as the second argument as the extension function's
1.4 misho 11760: ** "auxiliary data". The pointer may then be retrieved by the current or any
11761: ** future invocation of the same fts5 extension function made as part of
1.4.2.2 misho 11762: ** the same MATCH query using the xGetAuxdata() API.
1.4 misho 11763: **
11764: ** Each extension function is allocated a single auxiliary data slot for
1.4.2.3 ! misho 11765: ** each FTS query (MATCH expression). If the extension function is invoked
! 11766: ** more than once for a single FTS query, then all invocations share a
1.4 misho 11767: ** single auxiliary data context.
11768: **
11769: ** If there is already an auxiliary data pointer when this function is
11770: ** invoked, then it is replaced by the new pointer. If an xDelete callback
11771: ** was specified along with the original pointer, it is invoked at this
11772: ** point.
11773: **
11774: ** The xDelete callback, if one is specified, is also invoked on the
11775: ** auxiliary data pointer after the FTS5 query has finished.
11776: **
1.4.2.2 misho 11777: ** If an error (e.g. an OOM condition) occurs within this function,
1.4 misho 11778: ** the auxiliary data is set to NULL and an error code returned. If the
11779: ** xDelete parameter was not NULL, it is invoked on the auxiliary data
11780: ** pointer before returning.
11781: **
11782: **
11783: ** xGetAuxdata(pFts5, bClear)
11784: **
1.4.2.3 ! misho 11785: ** Returns the current auxiliary data pointer for the fts5 extension
1.4 misho 11786: ** function. See the xSetAuxdata() method for details.
11787: **
11788: ** If the bClear argument is non-zero, then the auxiliary data is cleared
11789: ** (set to NULL) before this function returns. In this case the xDelete,
11790: ** if any, is not invoked.
11791: **
11792: **
11793: ** xRowCount(pFts5, pnRow)
11794: **
11795: ** This function is used to retrieve the total number of rows in the table.
11796: ** In other words, the same value that would be returned by:
11797: **
11798: ** SELECT count(*) FROM ftstable;
11799: **
11800: ** xPhraseFirst()
11801: ** This function is used, along with type Fts5PhraseIter and the xPhraseNext
11802: ** method, to iterate through all instances of a single query phrase within
11803: ** the current row. This is the same information as is accessible via the
11804: ** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient
1.4.2.3 ! misho 11805: ** to use, this API may be faster under some circumstances. To iterate
1.4 misho 11806: ** through instances of phrase iPhrase, use the following code:
11807: **
11808: ** Fts5PhraseIter iter;
11809: ** int iCol, iOff;
11810: ** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);
11811: ** iCol>=0;
11812: ** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)
11813: ** ){
11814: ** // An instance of phrase iPhrase at offset iOff of column iCol
11815: ** }
11816: **
11817: ** The Fts5PhraseIter structure is defined above. Applications should not
11818: ** modify this structure directly - it should only be used as shown above
11819: ** with the xPhraseFirst() and xPhraseNext() API methods (and by
11820: ** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).
11821: **
11822: ** This API can be quite slow if used with an FTS5 table created with the
1.4.2.3 ! misho 11823: ** "detail=none" or "detail=column" option. If the FTS5 table is created
! 11824: ** with either "detail=none" or "detail=column" and "content=" option
1.4 misho 11825: ** (i.e. if it is a contentless table), then this API always iterates
11826: ** through an empty set (all calls to xPhraseFirst() set iCol to -1).
11827: **
11828: ** xPhraseNext()
11829: ** See xPhraseFirst above.
11830: **
11831: ** xPhraseFirstColumn()
11832: ** This function and xPhraseNextColumn() are similar to the xPhraseFirst()
11833: ** and xPhraseNext() APIs described above. The difference is that instead
11834: ** of iterating through all instances of a phrase in the current row, these
11835: ** APIs are used to iterate through the set of columns in the current row
11836: ** that contain one or more instances of a specified phrase. For example:
11837: **
11838: ** Fts5PhraseIter iter;
11839: ** int iCol;
11840: ** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);
11841: ** iCol>=0;
11842: ** pApi->xPhraseNextColumn(pFts, &iter, &iCol)
11843: ** ){
11844: ** // Column iCol contains at least one instance of phrase iPhrase
11845: ** }
11846: **
11847: ** This API can be quite slow if used with an FTS5 table created with the
1.4.2.3 ! misho 11848: ** "detail=none" option. If the FTS5 table is created with either
! 11849: ** "detail=none" "content=" option (i.e. if it is a contentless table),
! 11850: ** then this API always iterates through an empty set (all calls to
1.4 misho 11851: ** xPhraseFirstColumn() set iCol to -1).
11852: **
11853: ** The information accessed using this API and its companion
11854: ** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
11855: ** (or xInst/xInstCount). The chief advantage of this API is that it is
11856: ** significantly more efficient than those alternatives when used with
1.4.2.3 ! misho 11857: ** "detail=column" tables.
1.4 misho 11858: **
11859: ** xPhraseNextColumn()
11860: ** See xPhraseFirstColumn above.
11861: */
11862: struct Fts5ExtensionApi {
11863: int iVersion; /* Currently always set to 3 */
11864:
11865: void *(*xUserData)(Fts5Context*);
11866:
11867: int (*xColumnCount)(Fts5Context*);
11868: int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow);
11869: int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken);
11870:
1.4.2.3 ! misho 11871: int (*xTokenize)(Fts5Context*,
1.4 misho 11872: const char *pText, int nText, /* Text to tokenize */
11873: void *pCtx, /* Context passed to xToken() */
11874: int (*xToken)(void*, int, const char*, int, int, int) /* Callback */
11875: );
11876:
11877: int (*xPhraseCount)(Fts5Context*);
11878: int (*xPhraseSize)(Fts5Context*, int iPhrase);
11879:
11880: int (*xInstCount)(Fts5Context*, int *pnInst);
11881: int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff);
11882:
11883: sqlite3_int64 (*xRowid)(Fts5Context*);
11884: int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn);
11885: int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken);
11886:
11887: int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData,
11888: int(*)(const Fts5ExtensionApi*,Fts5Context*,void*)
11889: );
11890: int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*));
11891: void *(*xGetAuxdata)(Fts5Context*, int bClear);
11892:
11893: int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
11894: void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff);
11895:
11896: int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*);
11897: void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol);
11898: };
11899:
1.4.2.3 ! misho 11900: /*
1.4 misho 11901: ** CUSTOM AUXILIARY FUNCTIONS
11902: *************************************************************************/
11903:
11904: /*************************************************************************
11905: ** CUSTOM TOKENIZERS
11906: **
1.4.2.3 ! misho 11907: ** Applications may also register custom tokenizer types. A tokenizer
! 11908: ** is registered by providing fts5 with a populated instance of the
1.4 misho 11909: ** following structure. All structure methods must be defined, setting
11910: ** any member of the fts5_tokenizer struct to NULL leads to undefined
11911: ** behaviour. The structure methods are expected to function as follows:
11912: **
11913: ** xCreate:
11914: ** This function is used to allocate and initialize a tokenizer instance.
11915: ** A tokenizer instance is required to actually tokenize text.
11916: **
11917: ** The first argument passed to this function is a copy of the (void*)
11918: ** pointer provided by the application when the fts5_tokenizer object
1.4.2.3 ! misho 11919: ** was registered with FTS5 (the third argument to xCreateTokenizer()).
1.4 misho 11920: ** The second and third arguments are an array of nul-terminated strings
11921: ** containing the tokenizer arguments, if any, specified following the
11922: ** tokenizer name as part of the CREATE VIRTUAL TABLE statement used
11923: ** to create the FTS5 table.
11924: **
1.4.2.3 ! misho 11925: ** The final argument is an output variable. If successful, (*ppOut)
1.4 misho 11926: ** should be set to point to the new tokenizer handle and SQLITE_OK
11927: ** returned. If an error occurs, some value other than SQLITE_OK should
1.4.2.3 ! misho 11928: ** be returned. In this case, fts5 assumes that the final value of *ppOut
1.4 misho 11929: ** is undefined.
11930: **
11931: ** xDelete:
11932: ** This function is invoked to delete a tokenizer handle previously
11933: ** allocated using xCreate(). Fts5 guarantees that this function will
11934: ** be invoked exactly once for each successful call to xCreate().
11935: **
11936: ** xTokenize:
1.4.2.3 ! misho 11937: ** This function is expected to tokenize the nText byte string indicated
1.4 misho 11938: ** by argument pText. pText may or may not be nul-terminated. The first
11939: ** argument passed to this function is a pointer to an Fts5Tokenizer object
11940: ** returned by an earlier call to xCreate().
11941: **
11942: ** The second argument indicates the reason that FTS5 is requesting
11943: ** tokenization of the supplied text. This is always one of the following
11944: ** four values:
11945: **
11946: ** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into
11947: ** or removed from the FTS table. The tokenizer is being invoked to
11948: ** determine the set of tokens to add to (or delete from) the
11949: ** FTS index.
11950: **
1.4.2.3 ! misho 11951: ** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed
! 11952: ** against the FTS index. The tokenizer is being called to tokenize
1.4 misho 11953: ** a bareword or quoted string specified as part of the query.
11954: **
11955: ** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as
11956: ** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is
11957: ** followed by a "*" character, indicating that the last token
11958: ** returned by the tokenizer will be treated as a token prefix.
11959: **
1.4.2.3 ! misho 11960: ** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to
1.4 misho 11961: ** satisfy an fts5_api.xTokenize() request made by an auxiliary
11962: ** function. Or an fts5_api.xColumnSize() request made by the same
1.4.2.3 ! misho 11963: ** on a columnsize=0 database.
1.4 misho 11964: ** </ul>
11965: **
11966: ** For each token in the input string, the supplied callback xToken() must
11967: ** be invoked. The first argument to it should be a copy of the pointer
11968: ** passed as the second argument to xTokenize(). The third and fourth
11969: ** arguments are a pointer to a buffer containing the token text, and the
11970: ** size of the token in bytes. The 4th and 5th arguments are the byte offsets
11971: ** of the first byte of and first byte immediately following the text from
11972: ** which the token is derived within the input.
11973: **
11974: ** The second argument passed to the xToken() callback ("tflags") should
1.4.2.3 ! misho 11975: ** normally be set to 0. The exception is if the tokenizer supports
1.4 misho 11976: ** synonyms. In this case see the discussion below for details.
11977: **
1.4.2.3 ! misho 11978: ** FTS5 assumes the xToken() callback is invoked for each token in the
1.4 misho 11979: ** order that they occur within the input text.
11980: **
11981: ** If an xToken() callback returns any value other than SQLITE_OK, then
11982: ** the tokenization should be abandoned and the xTokenize() method should
11983: ** immediately return a copy of the xToken() return value. Or, if the
11984: ** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally,
11985: ** if an error occurs with the xTokenize() implementation itself, it
11986: ** may abandon the tokenization and return any error code other than
11987: ** SQLITE_OK or SQLITE_DONE.
11988: **
11989: ** SYNONYM SUPPORT
11990: **
11991: ** Custom tokenizers may also support synonyms. Consider a case in which a
1.4.2.3 ! misho 11992: ** user wishes to query for a phrase such as "first place". Using the
1.4 misho 11993: ** built-in tokenizers, the FTS5 query 'first + place' will match instances
11994: ** of "first place" within the document set, but not alternative forms
11995: ** such as "1st place". In some applications, it would be better to match
11996: ** all instances of "first place" or "1st place" regardless of which form
11997: ** the user specified in the MATCH query text.
11998: **
11999: ** There are several ways to approach this in FTS5:
12000: **
1.4.2.3 ! misho 12001: ** <ol><li> By mapping all synonyms to a single token. In this case, using
! 12002: ** the above example, this means that the tokenizer returns the
1.4 misho 12003: ** same token for inputs "first" and "1st". Say that token is in
12004: ** fact "first", so that when the user inserts the document "I won
12005: ** 1st place" entries are added to the index for tokens "i", "won",
12006: ** "first" and "place". If the user then queries for '1st + place',
12007: ** the tokenizer substitutes "first" for "1st" and the query works
12008: ** as expected.
12009: **
1.4.2.2 misho 12010: ** <li> By querying the index for all synonyms of each query term
12011: ** separately. In this case, when tokenizing query text, the
1.4.2.3 ! misho 12012: ** tokenizer may provide multiple synonyms for a single term
! 12013: ** within the document. FTS5 then queries the index for each
1.4.2.2 misho 12014: ** synonym individually. For example, faced with the query:
1.4 misho 12015: **
12016: ** <codeblock>
12017: ** ... MATCH 'first place'</codeblock>
12018: **
12019: ** the tokenizer offers both "1st" and "first" as synonyms for the
1.4.2.3 ! misho 12020: ** first token in the MATCH query and FTS5 effectively runs a query
1.4 misho 12021: ** similar to:
12022: **
12023: ** <codeblock>
12024: ** ... MATCH '(first OR 1st) place'</codeblock>
12025: **
12026: ** except that, for the purposes of auxiliary functions, the query
1.4.2.3 ! misho 12027: ** still appears to contain just two phrases - "(first OR 1st)"
1.4 misho 12028: ** being treated as a single phrase.
12029: **
12030: ** <li> By adding multiple synonyms for a single term to the FTS index.
12031: ** Using this method, when tokenizing document text, the tokenizer
1.4.2.3 ! misho 12032: ** provides multiple synonyms for each token. So that when a
1.4 misho 12033: ** document such as "I won first place" is tokenized, entries are
12034: ** added to the FTS index for "i", "won", "first", "1st" and
12035: ** "place".
12036: **
12037: ** This way, even if the tokenizer does not provide synonyms
1.4.2.2 misho 12038: ** when tokenizing query text (it should not - to do so would be
1.4.2.3 ! misho 12039: ** inefficient), it doesn't matter if the user queries for
1.4.2.2 misho 12040: ** 'first + place' or '1st + place', as there are entries in the
1.4 misho 12041: ** FTS index corresponding to both forms of the first token.
12042: ** </ol>
12043: **
12044: ** Whether it is parsing document or query text, any call to xToken that
12045: ** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit
12046: ** is considered to supply a synonym for the previous token. For example,
12047: ** when parsing the document "I won first place", a tokenizer that supports
12048: ** synonyms would call xToken() 5 times, as follows:
12049: **
12050: ** <codeblock>
12051: ** xToken(pCtx, 0, "i", 1, 0, 1);
12052: ** xToken(pCtx, 0, "won", 3, 2, 5);
12053: ** xToken(pCtx, 0, "first", 5, 6, 11);
12054: ** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11);
12055: ** xToken(pCtx, 0, "place", 5, 12, 17);
12056: **</codeblock>
12057: **
12058: ** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time
12059: ** xToken() is called. Multiple synonyms may be specified for a single token
1.4.2.3 ! misho 12060: ** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence.
1.4 misho 12061: ** There is no limit to the number of synonyms that may be provided for a
12062: ** single token.
12063: **
1.4.2.3 ! misho 12064: ** In many cases, method (1) above is the best approach. It does not add
1.4 misho 12065: ** extra data to the FTS index or require FTS5 to query for multiple terms,
12066: ** so it is efficient in terms of disk space and query speed. However, it
12067: ** does not support prefix queries very well. If, as suggested above, the
1.4.2.2 misho 12068: ** token "first" is substituted for "1st" by the tokenizer, then the query:
1.4 misho 12069: **
12070: ** <codeblock>
12071: ** ... MATCH '1s*'</codeblock>
12072: **
12073: ** will not match documents that contain the token "1st" (as the tokenizer
12074: ** will probably not map "1s" to any prefix of "first").
12075: **
1.4.2.3 ! misho 12076: ** For full prefix support, method (3) may be preferred. In this case,
1.4 misho 12077: ** because the index contains entries for both "first" and "1st", prefix
12078: ** queries such as 'fi*' or '1s*' will match correctly. However, because
12079: ** extra entries are added to the FTS index, this method uses more space
12080: ** within the database.
12081: **
12082: ** Method (2) offers a midpoint between (1) and (3). Using this method,
1.4.2.3 ! misho 12083: ** a query such as '1s*' will match documents that contain the literal
1.4 misho 12084: ** token "1st", but not "first" (assuming the tokenizer is not able to
12085: ** provide synonyms for prefixes). However, a non-prefix query like '1st'
12086: ** will match against "1st" and "first". This method does not require
1.4.2.3 ! misho 12087: ** extra disk space, as no extra entries are added to the FTS index.
1.4 misho 12088: ** On the other hand, it may require more CPU cycles to run MATCH queries,
12089: ** as separate queries of the FTS index are required for each synonym.
12090: **
12091: ** When using methods (2) or (3), it is important that the tokenizer only
12092: ** provide synonyms when tokenizing document text (method (2)) or query
12093: ** text (method (3)), not both. Doing so will not cause any errors, but is
12094: ** inefficient.
12095: */
12096: typedef struct Fts5Tokenizer Fts5Tokenizer;
12097: typedef struct fts5_tokenizer fts5_tokenizer;
12098: struct fts5_tokenizer {
12099: int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
12100: void (*xDelete)(Fts5Tokenizer*);
1.4.2.3 ! misho 12101: int (*xTokenize)(Fts5Tokenizer*,
1.4 misho 12102: void *pCtx,
12103: int flags, /* Mask of FTS5_TOKENIZE_* flags */
1.4.2.3 ! misho 12104: const char *pText, int nText,
1.4 misho 12105: int (*xToken)(
12106: void *pCtx, /* Copy of 2nd argument to xTokenize() */
12107: int tflags, /* Mask of FTS5_TOKEN_* flags */
12108: const char *pToken, /* Pointer to buffer containing token */
12109: int nToken, /* Size of token in bytes */
12110: int iStart, /* Byte offset of token within input text */
12111: int iEnd /* Byte offset of end of token within input text */
12112: )
12113: );
12114: };
12115:
12116: /* Flags that may be passed as the third argument to xTokenize() */
12117: #define FTS5_TOKENIZE_QUERY 0x0001
12118: #define FTS5_TOKENIZE_PREFIX 0x0002
12119: #define FTS5_TOKENIZE_DOCUMENT 0x0004
12120: #define FTS5_TOKENIZE_AUX 0x0008
12121:
12122: /* Flags that may be passed by the tokenizer implementation back to FTS5
12123: ** as the third argument to the supplied xToken callback. */
12124: #define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */
12125:
12126: /*
12127: ** END OF CUSTOM TOKENIZERS
12128: *************************************************************************/
12129:
12130: /*************************************************************************
12131: ** FTS5 EXTENSION REGISTRATION API
12132: */
12133: typedef struct fts5_api fts5_api;
12134: struct fts5_api {
12135: int iVersion; /* Currently always set to 2 */
12136:
12137: /* Create a new tokenizer */
12138: int (*xCreateTokenizer)(
12139: fts5_api *pApi,
12140: const char *zName,
12141: void *pContext,
12142: fts5_tokenizer *pTokenizer,
12143: void (*xDestroy)(void*)
12144: );
12145:
12146: /* Find an existing tokenizer */
12147: int (*xFindTokenizer)(
12148: fts5_api *pApi,
12149: const char *zName,
12150: void **ppContext,
12151: fts5_tokenizer *pTokenizer
12152: );
12153:
12154: /* Create a new auxiliary function */
12155: int (*xCreateFunction)(
12156: fts5_api *pApi,
12157: const char *zName,
12158: void *pContext,
12159: fts5_extension_function xFunction,
12160: void (*xDestroy)(void*)
12161: );
12162: };
12163:
12164: /*
12165: ** END OF REGISTRATION API
12166: *************************************************************************/
12167:
12168: #ifdef __cplusplus
12169: } /* end of the 'extern "C"' block */
12170: #endif
12171:
12172: #endif /* _FTS5_H */
12173:
12174: /******** End of fts5.h *********/
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