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drh75897232000-05-29 14:26:00 +00001/*
drhb19a2bc2001-09-16 00:13:26 +00002** 2001 September 15
drh75897232000-05-29 14:26:00 +00003**
drhb19a2bc2001-09-16 00:13:26 +00004** The author disclaims copyright to this source code. In place of
5** a legal notice, here is a blessing:
drh75897232000-05-29 14:26:00 +00006**
drhb19a2bc2001-09-16 00:13:26 +00007** 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.
drh75897232000-05-29 14:26:00 +000010**
11*************************************************************************
drhb19a2bc2001-09-16 00:13:26 +000012** This header file defines the interface that the SQLite library
drh6ed48bf2007-06-14 20:57:18 +000013** 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.
drh75897232000-05-29 14:26:00 +000017**
drh6ed48bf2007-06-14 20:57:18 +000018** Some of the definitions that are in this file are marked as
19** "experimental". Experimental interfaces are normally new
mihailima3f64902008-06-21 13:35:56 +000020** features recently added to SQLite. We do not anticipate changes
shane7c7c3112009-08-17 15:31:23 +000021** to experimental interfaces but reserve the right to make minor changes
22** if experience from use "in the wild" suggest such changes are prudent.
drh6ed48bf2007-06-14 20:57:18 +000023**
24** The official C-language API documentation for SQLite is derived
25** from comments in this file. This file is the authoritative source
26** on how SQLite interfaces are suppose to operate.
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.
drh75897232000-05-29 14:26:00 +000032*/
drh12057d52004-09-06 17:34:12 +000033#ifndef _SQLITE3_H_
34#define _SQLITE3_H_
drha18c5682000-10-08 22:20:57 +000035#include <stdarg.h> /* Needed for the definition of va_list */
drh75897232000-05-29 14:26:00 +000036
37/*
drh382c0242001-10-06 16:33:02 +000038** Make sure we can call this stuff from C++.
39*/
40#ifdef __cplusplus
41extern "C" {
42#endif
43
drh6d2069d2007-08-14 01:58:53 +000044
drh382c0242001-10-06 16:33:02 +000045/*
drh73be5012007-08-08 12:11:21 +000046** Add the ability to override 'extern'
47*/
48#ifndef SQLITE_EXTERN
49# define SQLITE_EXTERN extern
50#endif
51
52/*
drh4d6618f2008-09-22 17:54:46 +000053** These no-op macros are used in front of interfaces to mark those
54** interfaces as either deprecated or experimental. New applications
shane7c7c3112009-08-17 15:31:23 +000055** should not use deprecated interfaces - they are support for backwards
drh4d6618f2008-09-22 17:54:46 +000056** compatibility only. Application writers should be aware that
57** experimental interfaces are subject to change in point releases.
58**
59** These macros used to resolve to various kinds of compiler magic that
60** would generate warning messages when they were used. But that
61** compiler magic ended up generating such a flurry of bug reports
62** that we have taken it all out and gone back to using simple
63** noop macros.
shanea79c3cc2008-08-11 17:27:01 +000064*/
drh4d6618f2008-09-22 17:54:46 +000065#define SQLITE_DEPRECATED
66#define SQLITE_EXPERIMENTAL
shanea79c3cc2008-08-11 17:27:01 +000067
68/*
mihailim362cc832008-06-21 06:16:42 +000069** Ensure these symbols were not defined by some previous header file.
drhb86ccfb2003-01-28 23:13:10 +000070*/
drh1e284f42004-10-06 15:52:01 +000071#ifdef SQLITE_VERSION
72# undef SQLITE_VERSION
drh1e284f42004-10-06 15:52:01 +000073#endif
drh6ed48bf2007-06-14 20:57:18 +000074#ifdef SQLITE_VERSION_NUMBER
75# undef SQLITE_VERSION_NUMBER
76#endif
danielk197799ba19e2005-02-05 07:33:34 +000077
78/*
drh1e15c032009-12-08 15:16:54 +000079** CAPI3REF: Compile-Time Library Version Numbers
drh6ed48bf2007-06-14 20:57:18 +000080**
drh1e15c032009-12-08 15:16:54 +000081** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
82** evaluates to a string literal that is the SQLite version in the
83** format "X.Y.Z" where X is the major version number (always 3 for
84** SQLite3) and Y is the minor version number and Z is the release number.)^
85** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
86** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
87** numbers used in [SQLITE_VERSION].)^
88** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
89** be larger than the release from which it is derived. Either Y will
90** be held constant and Z will be incremented or else Y will be incremented
91** and Z will be reset to zero.
drh6aa5f152009-08-19 15:57:07 +000092**
drh47baebc2009-08-14 16:01:24 +000093** Since version 3.6.18, SQLite source code has been stored in the
drh1e15c032009-12-08 15:16:54 +000094** <a href="http://www.fossil-scm.org/">Fossil configuration management
95** system</a>. ^The SQLITE_SOURCE_ID macro evalutes to
96** a string which identifies a particular check-in of SQLite
97** within its configuration management system. ^The SQLITE_SOURCE_ID
98** string contains the date and time of the check-in (UTC) and an SHA1
99** hash of the entire source tree.
drh47baebc2009-08-14 16:01:24 +0000100**
drh6aa5f152009-08-19 15:57:07 +0000101** See also: [sqlite3_libversion()],
drh4e0b31c2009-09-02 19:04:24 +0000102** [sqlite3_libversion_number()], [sqlite3_sourceid()],
103** [sqlite_version()] and [sqlite_source_id()].
danielk197799ba19e2005-02-05 07:33:34 +0000104*/
drh47baebc2009-08-14 16:01:24 +0000105#define SQLITE_VERSION "--VERS--"
106#define SQLITE_VERSION_NUMBER --VERSION-NUMBER--
107#define SQLITE_SOURCE_ID "--SOURCE-ID--"
drhb86ccfb2003-01-28 23:13:10 +0000108
109/*
drh1e15c032009-12-08 15:16:54 +0000110** CAPI3REF: Run-Time Library Version Numbers
shanehdc97a8c2010-02-23 20:08:35 +0000111** KEYWORDS: sqlite3_version, sqlite3_sourceid
drh6ed48bf2007-06-14 20:57:18 +0000112**
drh47baebc2009-08-14 16:01:24 +0000113** These interfaces provide the same information as the [SQLITE_VERSION],
drh1e15c032009-12-08 15:16:54 +0000114** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
drhd68eee02009-12-11 03:44:18 +0000115** but are associated with the library instead of the header file. ^(Cautious
drh4e0b31c2009-09-02 19:04:24 +0000116** programmers might include assert() statements in their application to
117** verify that values returned by these interfaces match the macros in
118** the header, and thus insure that the application is
drh6aa5f152009-08-19 15:57:07 +0000119** compiled with matching library and header files.
120**
121** <blockquote><pre>
122** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
drh4e0b31c2009-09-02 19:04:24 +0000123** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
drh1e15c032009-12-08 15:16:54 +0000124** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
drhd68eee02009-12-11 03:44:18 +0000125** </pre></blockquote>)^
drh6ed48bf2007-06-14 20:57:18 +0000126**
drh1e15c032009-12-08 15:16:54 +0000127** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
128** macro. ^The sqlite3_libversion() function returns a pointer to the
129** to the sqlite3_version[] string constant. The sqlite3_libversion()
130** function is provided for use in DLLs since DLL users usually do not have
131** direct access to string constants within the DLL. ^The
132** sqlite3_libversion_number() function returns an integer equal to
shanehbdea6d12010-02-23 04:19:54 +0000133** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns
134** a pointer to a string constant whose value is the same as the
shanehdc97a8c2010-02-23 20:08:35 +0000135** [SQLITE_SOURCE_ID] C preprocessor macro.
drh33c1be32008-01-30 16:16:14 +0000136**
drh4e0b31c2009-09-02 19:04:24 +0000137** See also: [sqlite_version()] and [sqlite_source_id()].
drhb217a572000-08-22 13:40:18 +0000138*/
drh73be5012007-08-08 12:11:21 +0000139SQLITE_EXTERN const char sqlite3_version[];
drha3f70cb2004-09-30 14:24:50 +0000140const char *sqlite3_libversion(void);
drh47baebc2009-08-14 16:01:24 +0000141const char *sqlite3_sourceid(void);
danielk197799ba19e2005-02-05 07:33:34 +0000142int sqlite3_libversion_number(void);
143
144/*
shanehdc97a8c2010-02-23 20:08:35 +0000145** CAPI3REF: Run-Time Library Compilation Options Diagnostics
shanehdc97a8c2010-02-23 20:08:35 +0000146**
147** ^The sqlite3_compileoption_used() function returns 0 or 1
148** indicating whether the specified option was defined at
149** compile time. ^The SQLITE_ prefix may be omitted from the
150** option name passed to sqlite3_compileoption_used().
151**
152** ^The sqlite3_compileoption_get() function allows interating
153** over the list of options that were defined at compile time by
154** returning the N-th compile time option string. ^If N is out of range,
155** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
156** prefix is omitted from any strings returned by
157** sqlite3_compileoption_get().
158**
159** ^Support for the diagnostic functions sqlite3_compileoption_used()
160** and sqlite3_compileoption_get() may be omitted by specifing the
drh71caabf2010-02-26 15:39:24 +0000161** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
shanehdc97a8c2010-02-23 20:08:35 +0000162**
drh71caabf2010-02-26 15:39:24 +0000163** See also: SQL functions [sqlite_compileoption_used()] and
164** [sqlite_compileoption_get()] and the [compile_options pragma].
shanehdc97a8c2010-02-23 20:08:35 +0000165*/
dan98f0c362010-03-22 04:32:13 +0000166#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
shanehdc97a8c2010-02-23 20:08:35 +0000167int sqlite3_compileoption_used(const char *zOptName);
drh380083c2010-02-23 20:32:15 +0000168const char *sqlite3_compileoption_get(int N);
dan98f0c362010-03-22 04:32:13 +0000169#endif
drhefad9992004-06-22 12:13:55 +0000170
drh75897232000-05-29 14:26:00 +0000171/*
drhd68eee02009-12-11 03:44:18 +0000172** CAPI3REF: Test To See If The Library Is Threadsafe
173**
174** ^The sqlite3_threadsafe() function returns zero if and only if
175** SQLite was compiled mutexing code omitted due to the
176** [SQLITE_THREADSAFE] compile-time option being set to 0.
drhb67e8bf2007-08-30 20:09:48 +0000177**
drh33c1be32008-01-30 16:16:14 +0000178** SQLite can be compiled with or without mutexes. When
drh6aa5f152009-08-19 15:57:07 +0000179** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
drhafacce02008-09-02 21:35:03 +0000180** are enabled and SQLite is threadsafe. When the
181** [SQLITE_THREADSAFE] macro is 0,
drh33c1be32008-01-30 16:16:14 +0000182** the mutexes are omitted. Without the mutexes, it is not safe
mihailim362cc832008-06-21 06:16:42 +0000183** to use SQLite concurrently from more than one thread.
drhb67e8bf2007-08-30 20:09:48 +0000184**
mihailim362cc832008-06-21 06:16:42 +0000185** Enabling mutexes incurs a measurable performance penalty.
drh33c1be32008-01-30 16:16:14 +0000186** So if speed is of utmost importance, it makes sense to disable
187** the mutexes. But for maximum safety, mutexes should be enabled.
drhd68eee02009-12-11 03:44:18 +0000188** ^The default behavior is for mutexes to be enabled.
drh33c1be32008-01-30 16:16:14 +0000189**
drh6aa5f152009-08-19 15:57:07 +0000190** This interface can be used by an application to make sure that the
drh33c1be32008-01-30 16:16:14 +0000191** version of SQLite that it is linking against was compiled with
drh4766b292008-06-26 02:53:02 +0000192** the desired setting of the [SQLITE_THREADSAFE] macro.
193**
194** This interface only reports on the compile-time mutex setting
195** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
drhd68eee02009-12-11 03:44:18 +0000196** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
drh4766b292008-06-26 02:53:02 +0000197** can be fully or partially disabled using a call to [sqlite3_config()]
198** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
drhd68eee02009-12-11 03:44:18 +0000199** or [SQLITE_CONFIG_MUTEX]. ^(The return value of the
200** sqlite3_threadsafe() function shows only the compile-time setting of
201** thread safety, not any run-time changes to that setting made by
202** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
203** is unchanged by calls to sqlite3_config().)^
drh33c1be32008-01-30 16:16:14 +0000204**
drhafacce02008-09-02 21:35:03 +0000205** See the [threading mode] documentation for additional information.
drhb67e8bf2007-08-30 20:09:48 +0000206*/
207int sqlite3_threadsafe(void);
208
209/*
drhd68eee02009-12-11 03:44:18 +0000210** CAPI3REF: Database Connection Handle
drha06f17f2008-05-11 11:07:06 +0000211** KEYWORDS: {database connection} {database connections}
drh6ed48bf2007-06-14 20:57:18 +0000212**
mihailim362cc832008-06-21 06:16:42 +0000213** Each open SQLite database is represented by a pointer to an instance of
214** the opaque structure named "sqlite3". It is useful to think of an sqlite3
drh8bacf972007-08-25 16:21:29 +0000215** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
mihailim362cc832008-06-21 06:16:42 +0000216** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
217** is its destructor. There are many other interfaces (such as
218** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
219** [sqlite3_busy_timeout()] to name but three) that are methods on an
220** sqlite3 object.
drh75897232000-05-29 14:26:00 +0000221*/
222typedef struct sqlite3 sqlite3;
223
drh75897232000-05-29 14:26:00 +0000224/*
drhd68eee02009-12-11 03:44:18 +0000225** CAPI3REF: 64-Bit Integer Types
drh33c1be32008-01-30 16:16:14 +0000226** KEYWORDS: sqlite_int64 sqlite_uint64
drh6ed48bf2007-06-14 20:57:18 +0000227**
drh33c1be32008-01-30 16:16:14 +0000228** Because there is no cross-platform way to specify 64-bit integer types
drhfddfa2d2007-12-05 18:05:16 +0000229** SQLite includes typedefs for 64-bit signed and unsigned integers.
drh6ed48bf2007-06-14 20:57:18 +0000230**
mihailim362cc832008-06-21 06:16:42 +0000231** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
232** The sqlite_int64 and sqlite_uint64 types are supported for backwards
233** compatibility only.
drh33c1be32008-01-30 16:16:14 +0000234**
drhd68eee02009-12-11 03:44:18 +0000235** ^The sqlite3_int64 and sqlite_int64 types can store integer values
236** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
237** sqlite3_uint64 and sqlite_uint64 types can store integer values
238** between 0 and +18446744073709551615 inclusive.
drh75897232000-05-29 14:26:00 +0000239*/
drh27436af2006-03-28 23:57:17 +0000240#ifdef SQLITE_INT64_TYPE
drh9b8f4472006-04-04 01:54:55 +0000241 typedef SQLITE_INT64_TYPE sqlite_int64;
drh27436af2006-03-28 23:57:17 +0000242 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
243#elif defined(_MSC_VER) || defined(__BORLANDC__)
drh75897232000-05-29 14:26:00 +0000244 typedef __int64 sqlite_int64;
245 typedef unsigned __int64 sqlite_uint64;
246#else
247 typedef long long int sqlite_int64;
248 typedef unsigned long long int sqlite_uint64;
249#endif
drh6d2069d2007-08-14 01:58:53 +0000250typedef sqlite_int64 sqlite3_int64;
251typedef sqlite_uint64 sqlite3_uint64;
drh75897232000-05-29 14:26:00 +0000252
drhb37df7b2005-10-13 02:09:49 +0000253/*
254** If compiling for a processor that lacks floating point support,
mihailim362cc832008-06-21 06:16:42 +0000255** substitute integer for floating-point.
drhb37df7b2005-10-13 02:09:49 +0000256*/
257#ifdef SQLITE_OMIT_FLOATING_POINT
drh6d2069d2007-08-14 01:58:53 +0000258# define double sqlite3_int64
drhb37df7b2005-10-13 02:09:49 +0000259#endif
drh75897232000-05-29 14:26:00 +0000260
261/*
drhd68eee02009-12-11 03:44:18 +0000262** CAPI3REF: Closing A Database Connection
drh75897232000-05-29 14:26:00 +0000263**
drhd68eee02009-12-11 03:44:18 +0000264** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
265** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
266** successfullly destroyed and all associated resources are deallocated.
drh33c1be32008-01-30 16:16:14 +0000267**
drh7db29fb2009-10-20 14:23:09 +0000268** Applications must [sqlite3_finalize | finalize] all [prepared statements]
mihailim15194222008-06-22 09:55:14 +0000269** and [sqlite3_blob_close | close] all [BLOB handles] associated with
drhd68eee02009-12-11 03:44:18 +0000270** the [sqlite3] object prior to attempting to close the object. ^If
271** sqlite3_close() is called on a [database connection] that still has
272** outstanding [prepared statements] or [BLOB handles], then it returns
273** SQLITE_BUSY.
drh55b0cf02008-06-19 17:54:33 +0000274**
drhd68eee02009-12-11 03:44:18 +0000275** ^If [sqlite3_close()] is invoked while a transaction is open,
drh55b0cf02008-06-19 17:54:33 +0000276** the transaction is automatically rolled back.
drh33c1be32008-01-30 16:16:14 +0000277**
drh8b39db12009-02-18 18:37:58 +0000278** The C parameter to [sqlite3_close(C)] must be either a NULL
279** pointer or an [sqlite3] object pointer obtained
280** from [sqlite3_open()], [sqlite3_open16()], or
281** [sqlite3_open_v2()], and not previously closed.
drhd68eee02009-12-11 03:44:18 +0000282** ^Calling sqlite3_close() with a NULL pointer argument is a
283** harmless no-op.
drh75897232000-05-29 14:26:00 +0000284*/
danielk1977f9d64d22004-06-19 08:18:07 +0000285int sqlite3_close(sqlite3 *);
drh75897232000-05-29 14:26:00 +0000286
287/*
288** The type for a callback function.
drh6ed48bf2007-06-14 20:57:18 +0000289** This is legacy and deprecated. It is included for historical
290** compatibility and is not documented.
drh75897232000-05-29 14:26:00 +0000291*/
drh12057d52004-09-06 17:34:12 +0000292typedef int (*sqlite3_callback)(void*,int,char**, char**);
drh75897232000-05-29 14:26:00 +0000293
294/*
drhd68eee02009-12-11 03:44:18 +0000295** CAPI3REF: One-Step Query Execution Interface
drh6ed48bf2007-06-14 20:57:18 +0000296**
drhd68eee02009-12-11 03:44:18 +0000297** The sqlite3_exec() interface is a convenience wrapper around
298** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
299** that allows an application to run multiple statements of SQL
300** without having to use a lot of C code.
drh75897232000-05-29 14:26:00 +0000301**
drhd68eee02009-12-11 03:44:18 +0000302** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
303** semicolon-separate SQL statements passed into its 2nd argument,
304** in the context of the [database connection] passed in as its 1st
305** argument. ^If the callback function of the 3rd argument to
306** sqlite3_exec() is not NULL, then it is invoked for each result row
307** coming out of the evaluated SQL statements. ^The 4th argument to
308** to sqlite3_exec() is relayed through to the 1st argument of each
309** callback invocation. ^If the callback pointer to sqlite3_exec()
310** is NULL, then no callback is ever invoked and result rows are
311** ignored.
drh35c61902008-05-20 15:44:30 +0000312**
drhd68eee02009-12-11 03:44:18 +0000313** ^If an error occurs while evaluating the SQL statements passed into
314** sqlite3_exec(), then execution of the current statement stops and
315** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
316** is not NULL then any error message is written into memory obtained
317** from [sqlite3_malloc()] and passed back through the 5th parameter.
318** To avoid memory leaks, the application should invoke [sqlite3_free()]
319** on error message strings returned through the 5th parameter of
320** of sqlite3_exec() after the error message string is no longer needed.
321** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
322** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
323** NULL before returning.
drh35c61902008-05-20 15:44:30 +0000324**
drhd68eee02009-12-11 03:44:18 +0000325** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
326** routine returns SQLITE_ABORT without invoking the callback again and
327** without running any subsequent SQL statements.
drh75897232000-05-29 14:26:00 +0000328**
drhd68eee02009-12-11 03:44:18 +0000329** ^The 2nd argument to the sqlite3_exec() callback function is the
330** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
331** callback is an array of pointers to strings obtained as if from
332** [sqlite3_column_text()], one for each column. ^If an element of a
333** result row is NULL then the corresponding string pointer for the
334** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
335** sqlite3_exec() callback is an array of pointers to strings where each
336** entry represents the name of corresponding result column as obtained
337** from [sqlite3_column_name()].
mihailima3f64902008-06-21 13:35:56 +0000338**
drhd68eee02009-12-11 03:44:18 +0000339** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
340** to an empty string, or a pointer that contains only whitespace and/or
341** SQL comments, then no SQL statements are evaluated and the database
342** is not changed.
drh75897232000-05-29 14:26:00 +0000343**
drhd68eee02009-12-11 03:44:18 +0000344** Restrictions:
drh75897232000-05-29 14:26:00 +0000345**
drhd68eee02009-12-11 03:44:18 +0000346** <ul>
347** <li> The application must insure that the 1st parameter to sqlite3_exec()
348** is a valid and open [database connection].
349** <li> The application must not close [database connection] specified by
350** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
351** <li> The application must not modify the SQL statement text passed into
352** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
353** </ul>
drh75897232000-05-29 14:26:00 +0000354*/
danielk19776f8a5032004-05-10 10:34:51 +0000355int sqlite3_exec(
drh6ed48bf2007-06-14 20:57:18 +0000356 sqlite3*, /* An open database */
shane236ce972008-05-30 15:35:30 +0000357 const char *sql, /* SQL to be evaluated */
drh6ed48bf2007-06-14 20:57:18 +0000358 int (*callback)(void*,int,char**,char**), /* Callback function */
359 void *, /* 1st argument to callback */
360 char **errmsg /* Error msg written here */
drh75897232000-05-29 14:26:00 +0000361);
362
drh58b95762000-06-02 01:17:37 +0000363/*
drhd68eee02009-12-11 03:44:18 +0000364** CAPI3REF: Result Codes
drh33c1be32008-01-30 16:16:14 +0000365** KEYWORDS: SQLITE_OK {error code} {error codes}
mihailimefc8e8a2008-06-21 16:47:09 +0000366** KEYWORDS: {result code} {result codes}
drh6ed48bf2007-06-14 20:57:18 +0000367**
368** Many SQLite functions return an integer result code from the set shown
drh33c1be32008-01-30 16:16:14 +0000369** here in order to indicates success or failure.
drh6ed48bf2007-06-14 20:57:18 +0000370**
drh4766b292008-06-26 02:53:02 +0000371** New error codes may be added in future versions of SQLite.
372**
drh6ed48bf2007-06-14 20:57:18 +0000373** See also: [SQLITE_IOERR_READ | extended result codes]
drh58b95762000-06-02 01:17:37 +0000374*/
drh717e6402001-09-27 03:22:32 +0000375#define SQLITE_OK 0 /* Successful result */
drh15b9a152006-01-31 20:49:13 +0000376/* beginning-of-error-codes */
drh717e6402001-09-27 03:22:32 +0000377#define SQLITE_ERROR 1 /* SQL error or missing database */
drh89e0dde2007-12-12 12:25:21 +0000378#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
drh717e6402001-09-27 03:22:32 +0000379#define SQLITE_PERM 3 /* Access permission denied */
380#define SQLITE_ABORT 4 /* Callback routine requested an abort */
381#define SQLITE_BUSY 5 /* The database file is locked */
382#define SQLITE_LOCKED 6 /* A table in the database is locked */
383#define SQLITE_NOMEM 7 /* A malloc() failed */
384#define SQLITE_READONLY 8 /* Attempt to write a readonly database */
drh24cd67e2004-05-10 16:18:47 +0000385#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
drh717e6402001-09-27 03:22:32 +0000386#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
387#define SQLITE_CORRUPT 11 /* The database disk image is malformed */
drh2db0bbc2005-08-11 02:10:18 +0000388#define SQLITE_NOTFOUND 12 /* NOT USED. Table or record not found */
drh717e6402001-09-27 03:22:32 +0000389#define SQLITE_FULL 13 /* Insertion failed because database is full */
390#define SQLITE_CANTOPEN 14 /* Unable to open the database file */
drh4f0ee682007-03-30 20:43:40 +0000391#define SQLITE_PROTOCOL 15 /* NOT USED. Database lock protocol error */
drh24cd67e2004-05-10 16:18:47 +0000392#define SQLITE_EMPTY 16 /* Database is empty */
drh717e6402001-09-27 03:22:32 +0000393#define SQLITE_SCHEMA 17 /* The database schema changed */
drhc797d4d2007-05-08 01:08:49 +0000394#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
danielk19776eb91d22007-09-21 04:27:02 +0000395#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
drh8aff1012001-12-22 14:49:24 +0000396#define SQLITE_MISMATCH 20 /* Data type mismatch */
drh247be432002-05-10 05:44:55 +0000397#define SQLITE_MISUSE 21 /* Library used incorrectly */
drh8766c342002-11-09 00:33:15 +0000398#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
drhed6c8672003-01-12 18:02:16 +0000399#define SQLITE_AUTH 23 /* Authorization denied */
drh1c2d8412003-03-31 00:30:47 +0000400#define SQLITE_FORMAT 24 /* Auxiliary database format error */
danielk19776f8a5032004-05-10 10:34:51 +0000401#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
drhc602f9a2004-02-12 19:01:04 +0000402#define SQLITE_NOTADB 26 /* File opened that is not a database file */
danielk19776f8a5032004-05-10 10:34:51 +0000403#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
404#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
drh15b9a152006-01-31 20:49:13 +0000405/* end-of-error-codes */
drh717e6402001-09-27 03:22:32 +0000406
drhaf9ff332002-01-16 21:00:27 +0000407/*
drhd68eee02009-12-11 03:44:18 +0000408** CAPI3REF: Extended Result Codes
drh33c1be32008-01-30 16:16:14 +0000409** KEYWORDS: {extended error code} {extended error codes}
mihailimefc8e8a2008-06-21 16:47:09 +0000410** KEYWORDS: {extended result code} {extended result codes}
drh4ac285a2006-09-15 07:28:50 +0000411**
drh6ed48bf2007-06-14 20:57:18 +0000412** In its default configuration, SQLite API routines return one of 26 integer
mihailim362cc832008-06-21 06:16:42 +0000413** [SQLITE_OK | result codes]. However, experience has shown that many of
414** these result codes are too coarse-grained. They do not provide as
drhf5befa02007-12-06 02:42:07 +0000415** much information about problems as programmers might like. In an effort to
drh6ed48bf2007-06-14 20:57:18 +0000416** address this, newer versions of SQLite (version 3.3.8 and later) include
417** support for additional result codes that provide more detailed information
drh33c1be32008-01-30 16:16:14 +0000418** about errors. The extended result codes are enabled or disabled
mihailim362cc832008-06-21 06:16:42 +0000419** on a per database connection basis using the
420** [sqlite3_extended_result_codes()] API.
mihailima3f64902008-06-21 13:35:56 +0000421**
drh33c1be32008-01-30 16:16:14 +0000422** Some of the available extended result codes are listed here.
423** One may expect the number of extended result codes will be expand
424** over time. Software that uses extended result codes should expect
425** to see new result codes in future releases of SQLite.
drh4ac285a2006-09-15 07:28:50 +0000426**
427** The SQLITE_OK result code will never be extended. It will always
428** be exactly zero.
drh4ac285a2006-09-15 07:28:50 +0000429*/
danielk1977861f7452008-06-05 11:39:11 +0000430#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
431#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
432#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
433#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
434#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
435#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
436#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
437#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
438#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
439#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
440#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
441#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
442#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
443#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
aswift5b1a2562008-08-22 00:22:35 +0000444#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
aswiftaebf4132008-11-21 00:10:35 +0000445#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
446#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
danielk1977404ca072009-03-16 13:19:36 +0000447#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8) )
448
drh4ac285a2006-09-15 07:28:50 +0000449/*
drhd68eee02009-12-11 03:44:18 +0000450** CAPI3REF: Flags For File Open Operations
drh6d2069d2007-08-14 01:58:53 +0000451**
mlcreechb2799412008-03-07 03:20:31 +0000452** These bit values are intended for use in the
drh33c1be32008-01-30 16:16:14 +0000453** 3rd parameter to the [sqlite3_open_v2()] interface and
454** in the 4th parameter to the xOpen method of the
drhd84f9462007-08-15 11:28:56 +0000455** [sqlite3_vfs] object.
drh6d2069d2007-08-14 01:58:53 +0000456*/
shane089b0a42009-05-14 03:21:28 +0000457#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
458#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
459#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
460#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
461#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
drh7ed97b92010-01-20 13:07:21 +0000462#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
shane089b0a42009-05-14 03:21:28 +0000463#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
464#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
465#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
466#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
467#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
468#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
469#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
470#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
471#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
drhf1f12682009-09-09 14:17:52 +0000472#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
473#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
drh6d2069d2007-08-14 01:58:53 +0000474
475/*
drhd68eee02009-12-11 03:44:18 +0000476** CAPI3REF: Device Characteristics
drh6d2069d2007-08-14 01:58:53 +0000477**
drh33c1be32008-01-30 16:16:14 +0000478** The xDeviceCapabilities method of the [sqlite3_io_methods]
drhfddfa2d2007-12-05 18:05:16 +0000479** object returns an integer which is a vector of the these
drh6d2069d2007-08-14 01:58:53 +0000480** bit values expressing I/O characteristics of the mass storage
481** device that holds the file that the [sqlite3_io_methods]
drh33c1be32008-01-30 16:16:14 +0000482** refers to.
drh6d2069d2007-08-14 01:58:53 +0000483**
drh33c1be32008-01-30 16:16:14 +0000484** The SQLITE_IOCAP_ATOMIC property means that all writes of
485** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
drh6d2069d2007-08-14 01:58:53 +0000486** mean that writes of blocks that are nnn bytes in size and
487** are aligned to an address which is an integer multiple of
drh33c1be32008-01-30 16:16:14 +0000488** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
drh6d2069d2007-08-14 01:58:53 +0000489** that when data is appended to a file, the data is appended
490** first then the size of the file is extended, never the other
drh33c1be32008-01-30 16:16:14 +0000491** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
drh6d2069d2007-08-14 01:58:53 +0000492** information is written to disk in the same order as calls
493** to xWrite().
494*/
495#define SQLITE_IOCAP_ATOMIC 0x00000001
496#define SQLITE_IOCAP_ATOMIC512 0x00000002
497#define SQLITE_IOCAP_ATOMIC1K 0x00000004
498#define SQLITE_IOCAP_ATOMIC2K 0x00000008
499#define SQLITE_IOCAP_ATOMIC4K 0x00000010
500#define SQLITE_IOCAP_ATOMIC8K 0x00000020
501#define SQLITE_IOCAP_ATOMIC16K 0x00000040
502#define SQLITE_IOCAP_ATOMIC32K 0x00000080
503#define SQLITE_IOCAP_ATOMIC64K 0x00000100
504#define SQLITE_IOCAP_SAFE_APPEND 0x00000200
505#define SQLITE_IOCAP_SEQUENTIAL 0x00000400
506
507/*
drhd68eee02009-12-11 03:44:18 +0000508** CAPI3REF: File Locking Levels
drh6d2069d2007-08-14 01:58:53 +0000509**
drh33c1be32008-01-30 16:16:14 +0000510** SQLite uses one of these integer values as the second
drh6d2069d2007-08-14 01:58:53 +0000511** argument to calls it makes to the xLock() and xUnlock() methods
drh33c1be32008-01-30 16:16:14 +0000512** of an [sqlite3_io_methods] object.
drh6d2069d2007-08-14 01:58:53 +0000513*/
514#define SQLITE_LOCK_NONE 0
515#define SQLITE_LOCK_SHARED 1
516#define SQLITE_LOCK_RESERVED 2
517#define SQLITE_LOCK_PENDING 3
518#define SQLITE_LOCK_EXCLUSIVE 4
519
520/*
drhd68eee02009-12-11 03:44:18 +0000521** CAPI3REF: Synchronization Type Flags
drh6d2069d2007-08-14 01:58:53 +0000522**
drh33c1be32008-01-30 16:16:14 +0000523** When SQLite invokes the xSync() method of an
mlcreechb2799412008-03-07 03:20:31 +0000524** [sqlite3_io_methods] object it uses a combination of
drhfddfa2d2007-12-05 18:05:16 +0000525** these integer values as the second argument.
drh6d2069d2007-08-14 01:58:53 +0000526**
drh33c1be32008-01-30 16:16:14 +0000527** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
drh6d2069d2007-08-14 01:58:53 +0000528** sync operation only needs to flush data to mass storage. Inode
drheb0d6292009-04-04 14:04:58 +0000529** information need not be flushed. If the lower four bits of the flag
530** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
531** If the lower four bits equal SQLITE_SYNC_FULL, that means
shane7ba429a2008-11-10 17:08:49 +0000532** to use Mac OS X style fullsync instead of fsync().
drh6d2069d2007-08-14 01:58:53 +0000533*/
drh6d2069d2007-08-14 01:58:53 +0000534#define SQLITE_SYNC_NORMAL 0x00002
535#define SQLITE_SYNC_FULL 0x00003
536#define SQLITE_SYNC_DATAONLY 0x00010
537
drh6d2069d2007-08-14 01:58:53 +0000538/*
drhd68eee02009-12-11 03:44:18 +0000539** CAPI3REF: OS Interface Open File Handle
drh6d2069d2007-08-14 01:58:53 +0000540**
drh6aa5f152009-08-19 15:57:07 +0000541** An [sqlite3_file] object represents an open file in the
542** [sqlite3_vfs | OS interface layer]. Individual OS interface
543** implementations will
drh6d2069d2007-08-14 01:58:53 +0000544** want to subclass this object by appending additional fields
drh4ff7fa02007-09-01 18:17:21 +0000545** for their own use. The pMethods entry is a pointer to an
drhd84f9462007-08-15 11:28:56 +0000546** [sqlite3_io_methods] object that defines methods for performing
547** I/O operations on the open file.
drh6d2069d2007-08-14 01:58:53 +0000548*/
549typedef struct sqlite3_file sqlite3_file;
550struct sqlite3_file {
drh153c62c2007-08-24 03:51:33 +0000551 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
drh6d2069d2007-08-14 01:58:53 +0000552};
553
554/*
drhd68eee02009-12-11 03:44:18 +0000555** CAPI3REF: OS Interface File Virtual Methods Object
drh6d2069d2007-08-14 01:58:53 +0000556**
drh4766b292008-06-26 02:53:02 +0000557** Every file opened by the [sqlite3_vfs] xOpen method populates an
558** [sqlite3_file] object (or, more commonly, a subclass of the
559** [sqlite3_file] object) with a pointer to an instance of this object.
560** This object defines the methods used to perform various operations
561** against the open file represented by the [sqlite3_file] object.
drhd84f9462007-08-15 11:28:56 +0000562**
drh9afedcc2009-06-19 22:50:31 +0000563** If the xOpen method sets the sqlite3_file.pMethods element
564** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
565** may be invoked even if the xOpen reported that it failed. The
566** only way to prevent a call to xClose following a failed xOpen
567** is for the xOpen to set the sqlite3_file.pMethods element to NULL.
568**
drhfddfa2d2007-12-05 18:05:16 +0000569** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
570** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
shane7ba429a2008-11-10 17:08:49 +0000571** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
mihailim362cc832008-06-21 06:16:42 +0000572** flag may be ORed in to indicate that only the data of the file
573** and not its inode needs to be synced.
mihailima3f64902008-06-21 13:35:56 +0000574**
drhd84f9462007-08-15 11:28:56 +0000575** The integer values to xLock() and xUnlock() are one of
drh4ff7fa02007-09-01 18:17:21 +0000576** <ul>
577** <li> [SQLITE_LOCK_NONE],
drh79491ab2007-09-04 12:00:00 +0000578** <li> [SQLITE_LOCK_SHARED],
drh4ff7fa02007-09-01 18:17:21 +0000579** <li> [SQLITE_LOCK_RESERVED],
580** <li> [SQLITE_LOCK_PENDING], or
581** <li> [SQLITE_LOCK_EXCLUSIVE].
582** </ul>
mihailima3f64902008-06-21 13:35:56 +0000583** xLock() increases the lock. xUnlock() decreases the lock.
mihailim362cc832008-06-21 06:16:42 +0000584** The xCheckReservedLock() method checks whether any database connection,
585** either in this process or in some other process, is holding a RESERVED,
drhd84f9462007-08-15 11:28:56 +0000586** PENDING, or EXCLUSIVE lock on the file. It returns true
mihailim362cc832008-06-21 06:16:42 +0000587** if such a lock exists and false otherwise.
mihailima3f64902008-06-21 13:35:56 +0000588**
drhcc6bb3e2007-08-31 16:11:35 +0000589** The xFileControl() method is a generic interface that allows custom
590** VFS implementations to directly control an open file using the
mihailim362cc832008-06-21 06:16:42 +0000591** [sqlite3_file_control()] interface. The second "op" argument is an
mihailima3f64902008-06-21 13:35:56 +0000592** integer opcode. The third argument is a generic pointer intended to
mihailim362cc832008-06-21 06:16:42 +0000593** point to a structure that may contain arguments or space in which to
drhcc6bb3e2007-08-31 16:11:35 +0000594** write return values. Potential uses for xFileControl() might be
595** functions to enable blocking locks with timeouts, to change the
596** locking strategy (for example to use dot-file locks), to inquire
drh9e33c2c2007-08-31 18:34:59 +0000597** about the status of a lock, or to break stale locks. The SQLite
mihailima3f64902008-06-21 13:35:56 +0000598** core reserves all opcodes less than 100 for its own use.
drh4ff7fa02007-09-01 18:17:21 +0000599** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
mihailim362cc832008-06-21 06:16:42 +0000600** Applications that define a custom xFileControl method should use opcodes
drh9e33c2c2007-08-31 18:34:59 +0000601** greater than 100 to avoid conflicts.
drhd84f9462007-08-15 11:28:56 +0000602**
603** The xSectorSize() method returns the sector size of the
604** device that underlies the file. The sector size is the
605** minimum write that can be performed without disturbing
606** other bytes in the file. The xDeviceCharacteristics()
607** method returns a bit vector describing behaviors of the
608** underlying device:
609**
610** <ul>
drh4ff7fa02007-09-01 18:17:21 +0000611** <li> [SQLITE_IOCAP_ATOMIC]
612** <li> [SQLITE_IOCAP_ATOMIC512]
613** <li> [SQLITE_IOCAP_ATOMIC1K]
614** <li> [SQLITE_IOCAP_ATOMIC2K]
615** <li> [SQLITE_IOCAP_ATOMIC4K]
616** <li> [SQLITE_IOCAP_ATOMIC8K]
617** <li> [SQLITE_IOCAP_ATOMIC16K]
618** <li> [SQLITE_IOCAP_ATOMIC32K]
619** <li> [SQLITE_IOCAP_ATOMIC64K]
620** <li> [SQLITE_IOCAP_SAFE_APPEND]
621** <li> [SQLITE_IOCAP_SEQUENTIAL]
drhd84f9462007-08-15 11:28:56 +0000622** </ul>
623**
624** The SQLITE_IOCAP_ATOMIC property means that all writes of
625** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
626** mean that writes of blocks that are nnn bytes in size and
627** are aligned to an address which is an integer multiple of
628** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
629** that when data is appended to a file, the data is appended
630** first then the size of the file is extended, never the other
631** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
632** information is written to disk in the same order as calls
633** to xWrite().
drh4c17c3f2008-11-07 00:06:18 +0000634**
635** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
636** in the unread portions of the buffer with zeros. A VFS that
637** fails to zero-fill short reads might seem to work. However,
638** failure to zero-fill short reads will eventually lead to
639** database corruption.
drh6d2069d2007-08-14 01:58:53 +0000640*/
641typedef struct sqlite3_io_methods sqlite3_io_methods;
642struct sqlite3_io_methods {
643 int iVersion;
644 int (*xClose)(sqlite3_file*);
drh79491ab2007-09-04 12:00:00 +0000645 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
646 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
647 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
drh6d2069d2007-08-14 01:58:53 +0000648 int (*xSync)(sqlite3_file*, int flags);
drh79491ab2007-09-04 12:00:00 +0000649 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
drh6d2069d2007-08-14 01:58:53 +0000650 int (*xLock)(sqlite3_file*, int);
651 int (*xUnlock)(sqlite3_file*, int);
danielk1977861f7452008-06-05 11:39:11 +0000652 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
drhcc6bb3e2007-08-31 16:11:35 +0000653 int (*xFileControl)(sqlite3_file*, int op, void *pArg);
drh6d2069d2007-08-14 01:58:53 +0000654 int (*xSectorSize)(sqlite3_file*);
655 int (*xDeviceCharacteristics)(sqlite3_file*);
drhd9e5c4f2010-05-12 18:01:39 +0000656 /* Methods above are valid for version 1 */
657 int (*xShmOpen)(sqlite3_file*);
658 int (*xShmSize)(sqlite3_file*, int reqSize, int *pNewSize);
drh5939f442010-05-18 13:27:12 +0000659 int (*xShmGet)(sqlite3_file*, int reqSize, int *pSize, void volatile**);
drhd9e5c4f2010-05-12 18:01:39 +0000660 int (*xShmRelease)(sqlite3_file*);
661 int (*xShmLock)(sqlite3_file*, int desiredLock, int *gotLock);
662 int (*xShmClose)(sqlite3_file*, int deleteFlag);
663 /* Methods above are valid for version 2 */
drh6d2069d2007-08-14 01:58:53 +0000664 /* Additional methods may be added in future releases */
665};
666
667/*
drhd68eee02009-12-11 03:44:18 +0000668** CAPI3REF: Standard File Control Opcodes
drh9e33c2c2007-08-31 18:34:59 +0000669**
670** These integer constants are opcodes for the xFileControl method
mihailim362cc832008-06-21 06:16:42 +0000671** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
drh9e33c2c2007-08-31 18:34:59 +0000672** interface.
673**
drh33c1be32008-01-30 16:16:14 +0000674** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
mlcreechb2799412008-03-07 03:20:31 +0000675** opcode causes the xFileControl method to write the current state of
drh9e33c2c2007-08-31 18:34:59 +0000676** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
677** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
drh33c1be32008-01-30 16:16:14 +0000678** into an integer that the pArg argument points to. This capability
drh9e33c2c2007-08-31 18:34:59 +0000679** is used during testing and only needs to be supported when SQLITE_TEST
680** is defined.
681*/
682#define SQLITE_FCNTL_LOCKSTATE 1
aswiftaebf4132008-11-21 00:10:35 +0000683#define SQLITE_GET_LOCKPROXYFILE 2
684#define SQLITE_SET_LOCKPROXYFILE 3
685#define SQLITE_LAST_ERRNO 4
drh9e33c2c2007-08-31 18:34:59 +0000686
687/*
drhd68eee02009-12-11 03:44:18 +0000688** CAPI3REF: Mutex Handle
drh6d2069d2007-08-14 01:58:53 +0000689**
drhd84f9462007-08-15 11:28:56 +0000690** The mutex module within SQLite defines [sqlite3_mutex] to be an
drh33c1be32008-01-30 16:16:14 +0000691** abstract type for a mutex object. The SQLite core never looks
692** at the internal representation of an [sqlite3_mutex]. It only
drhd84f9462007-08-15 11:28:56 +0000693** deals with pointers to the [sqlite3_mutex] object.
drh6bdec4a2007-08-16 19:40:16 +0000694**
695** Mutexes are created using [sqlite3_mutex_alloc()].
drh6d2069d2007-08-14 01:58:53 +0000696*/
697typedef struct sqlite3_mutex sqlite3_mutex;
698
699/*
drhd68eee02009-12-11 03:44:18 +0000700** CAPI3REF: OS Interface Object
drh6d2069d2007-08-14 01:58:53 +0000701**
mihailim362cc832008-06-21 06:16:42 +0000702** An instance of the sqlite3_vfs object defines the interface between
703** the SQLite core and the underlying operating system. The "vfs"
drhd84f9462007-08-15 11:28:56 +0000704** in the name of the object stands for "virtual file system".
drh6d2069d2007-08-14 01:58:53 +0000705**
mihailim362cc832008-06-21 06:16:42 +0000706** The value of the iVersion field is initially 1 but may be larger in
707** future versions of SQLite. Additional fields may be appended to this
drh4766b292008-06-26 02:53:02 +0000708** object when the iVersion value is increased. Note that the structure
709** of the sqlite3_vfs object changes in the transaction between
710** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
711** modified.
drh6bdec4a2007-08-16 19:40:16 +0000712**
drh4ff7fa02007-09-01 18:17:21 +0000713** The szOsFile field is the size of the subclassed [sqlite3_file]
drhd84f9462007-08-15 11:28:56 +0000714** structure used by this VFS. mxPathname is the maximum length of
715** a pathname in this VFS.
716**
drhb4d58ae2008-02-21 20:17:06 +0000717** Registered sqlite3_vfs objects are kept on a linked list formed by
drh79491ab2007-09-04 12:00:00 +0000718** the pNext pointer. The [sqlite3_vfs_register()]
719** and [sqlite3_vfs_unregister()] interfaces manage this list
720** in a thread-safe way. The [sqlite3_vfs_find()] interface
drh4766b292008-06-26 02:53:02 +0000721** searches the list. Neither the application code nor the VFS
722** implementation should use the pNext pointer.
drhd84f9462007-08-15 11:28:56 +0000723**
mihailima3f64902008-06-21 13:35:56 +0000724** The pNext field is the only field in the sqlite3_vfs
drh1cc8c442007-08-24 16:08:29 +0000725** structure that SQLite will ever modify. SQLite will only access
726** or modify this field while holding a particular static mutex.
727** The application should never modify anything within the sqlite3_vfs
728** object once the object has been registered.
729**
drhd84f9462007-08-15 11:28:56 +0000730** The zName field holds the name of the VFS module. The name must
731** be unique across all VFS modules.
732**
drh032ca702008-12-10 11:44:30 +0000733** SQLite will guarantee that the zFilename parameter to xOpen
drh4766b292008-06-26 02:53:02 +0000734** is either a NULL pointer or string obtained
735** from xFullPathname(). SQLite further guarantees that
736** the string will be valid and unchanged until xClose() is
drh9afedcc2009-06-19 22:50:31 +0000737** called. Because of the previous sentence,
drh4766b292008-06-26 02:53:02 +0000738** the [sqlite3_file] can safely store a pointer to the
drh6d2069d2007-08-14 01:58:53 +0000739** filename if it needs to remember the filename for some reason.
drh4766b292008-06-26 02:53:02 +0000740** If the zFilename parameter is xOpen is a NULL pointer then xOpen
drh9afedcc2009-06-19 22:50:31 +0000741** must invent its own temporary name for the file. Whenever the
drh4766b292008-06-26 02:53:02 +0000742** xFilename parameter is NULL it will also be the case that the
743** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
drhd84f9462007-08-15 11:28:56 +0000744**
drh032ca702008-12-10 11:44:30 +0000745** The flags argument to xOpen() includes all bits set in
drhf5befa02007-12-06 02:42:07 +0000746** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
747** or [sqlite3_open16()] is used, then flags includes at least
drh032ca702008-12-10 11:44:30 +0000748** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
drh6d2069d2007-08-14 01:58:53 +0000749** If xOpen() opens a file read-only then it sets *pOutFlags to
mihailim362cc832008-06-21 06:16:42 +0000750** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
751**
drh032ca702008-12-10 11:44:30 +0000752** SQLite will also add one of the following flags to the xOpen()
drh6d2069d2007-08-14 01:58:53 +0000753** call, depending on the object being opened:
mihailim362cc832008-06-21 06:16:42 +0000754**
drh6d2069d2007-08-14 01:58:53 +0000755** <ul>
756** <li> [SQLITE_OPEN_MAIN_DB]
757** <li> [SQLITE_OPEN_MAIN_JOURNAL]
758** <li> [SQLITE_OPEN_TEMP_DB]
759** <li> [SQLITE_OPEN_TEMP_JOURNAL]
drh33f4e022007-09-03 15:19:34 +0000760** <li> [SQLITE_OPEN_TRANSIENT_DB]
drh6d2069d2007-08-14 01:58:53 +0000761** <li> [SQLITE_OPEN_SUBJOURNAL]
762** <li> [SQLITE_OPEN_MASTER_JOURNAL]
drh032ca702008-12-10 11:44:30 +0000763** </ul>
drhd84f9462007-08-15 11:28:56 +0000764**
drh6d2069d2007-08-14 01:58:53 +0000765** The file I/O implementation can use the object type flags to
mihailim362cc832008-06-21 06:16:42 +0000766** change the way it deals with files. For example, an application
mlcreechb2799412008-03-07 03:20:31 +0000767** that does not care about crash recovery or rollback might make
768** the open of a journal file a no-op. Writes to this journal would
mihailim362cc832008-06-21 06:16:42 +0000769** also be no-ops, and any attempt to read the journal would return
770** SQLITE_IOERR. Or the implementation might recognize that a database
771** file will be doing page-aligned sector reads and writes in a random
mlcreechb2799412008-03-07 03:20:31 +0000772** order and set up its I/O subsystem accordingly.
mihailim362cc832008-06-21 06:16:42 +0000773**
774** SQLite might also add one of the following flags to the xOpen method:
775**
drh6d2069d2007-08-14 01:58:53 +0000776** <ul>
777** <li> [SQLITE_OPEN_DELETEONCLOSE]
778** <li> [SQLITE_OPEN_EXCLUSIVE]
779** </ul>
mihailim362cc832008-06-21 06:16:42 +0000780**
drh032ca702008-12-10 11:44:30 +0000781** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
782** deleted when it is closed. The [SQLITE_OPEN_DELETEONCLOSE]
mihailim362cc832008-06-21 06:16:42 +0000783** will be set for TEMP databases, journals and for subjournals.
mihailim04bcc002008-06-22 10:21:27 +0000784**
shane089b0a42009-05-14 03:21:28 +0000785** The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
786** with the [SQLITE_OPEN_CREATE] flag, which are both directly
787** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
788** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
789** SQLITE_OPEN_CREATE, is used to indicate that file should always
790** be created, and that it is an error if it already exists.
791** It is <i>not</i> used to indicate the file should be opened
792** for exclusive access.
mihailim362cc832008-06-21 06:16:42 +0000793**
drh032ca702008-12-10 11:44:30 +0000794** At least szOsFile bytes of memory are allocated by SQLite
mihailim362cc832008-06-21 06:16:42 +0000795** to hold the [sqlite3_file] structure passed as the third
drh032ca702008-12-10 11:44:30 +0000796** argument to xOpen. The xOpen method does not have to
drh9afedcc2009-06-19 22:50:31 +0000797** allocate the structure; it should just fill it in. Note that
798** the xOpen method must set the sqlite3_file.pMethods to either
799** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
800** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
801** element will be valid after xOpen returns regardless of the success
802** or failure of the xOpen call.
mihailim362cc832008-06-21 06:16:42 +0000803**
drh032ca702008-12-10 11:44:30 +0000804** The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
mihailim362cc832008-06-21 06:16:42 +0000805** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
806** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
drh032ca702008-12-10 11:44:30 +0000807** to test whether a file is at least readable. The file can be a
drh6d2069d2007-08-14 01:58:53 +0000808** directory.
mihailim362cc832008-06-21 06:16:42 +0000809**
drh032ca702008-12-10 11:44:30 +0000810** SQLite will always allocate at least mxPathname+1 bytes for the
811** output buffer xFullPathname. The exact size of the output buffer
812** is also passed as a parameter to both methods. If the output buffer
mihailim362cc832008-06-21 06:16:42 +0000813** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
814** handled as a fatal error by SQLite, vfs implementations should endeavor
815** to prevent this by setting mxPathname to a sufficiently large value.
816**
drhd84f9462007-08-15 11:28:56 +0000817** The xRandomness(), xSleep(), and xCurrentTime() interfaces
818** are not strictly a part of the filesystem, but they are
819** included in the VFS structure for completeness.
drh6d2069d2007-08-14 01:58:53 +0000820** The xRandomness() function attempts to return nBytes bytes
821** of good-quality randomness into zOut. The return value is
mihailim362cc832008-06-21 06:16:42 +0000822** the actual number of bytes of randomness obtained.
823** The xSleep() method causes the calling thread to sleep for at
drhd84f9462007-08-15 11:28:56 +0000824** least the number of microseconds given. The xCurrentTime()
mihailim362cc832008-06-21 06:16:42 +0000825** method returns a Julian Day Number for the current date and time.
drh032ca702008-12-10 11:44:30 +0000826**
drh6d2069d2007-08-14 01:58:53 +0000827*/
drhd84f9462007-08-15 11:28:56 +0000828typedef struct sqlite3_vfs sqlite3_vfs;
829struct sqlite3_vfs {
drhf2424c52010-04-26 00:04:55 +0000830 int iVersion; /* Structure version number (currently 2) */
drh6d2069d2007-08-14 01:58:53 +0000831 int szOsFile; /* Size of subclassed sqlite3_file */
drh6d2069d2007-08-14 01:58:53 +0000832 int mxPathname; /* Maximum file pathname length */
drhd84f9462007-08-15 11:28:56 +0000833 sqlite3_vfs *pNext; /* Next registered VFS */
drhd84f9462007-08-15 11:28:56 +0000834 const char *zName; /* Name of this virtual file system */
drh1cc8c442007-08-24 16:08:29 +0000835 void *pAppData; /* Pointer to application-specific data */
drh153c62c2007-08-24 03:51:33 +0000836 int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
drh6d2069d2007-08-14 01:58:53 +0000837 int flags, int *pOutFlags);
drh153c62c2007-08-24 03:51:33 +0000838 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
danielk1977861f7452008-06-05 11:39:11 +0000839 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
danielk1977adfb9b02007-09-17 07:02:56 +0000840 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
drh153c62c2007-08-24 03:51:33 +0000841 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
842 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
drh1875f7a2008-12-08 18:19:17 +0000843 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
drh153c62c2007-08-24 03:51:33 +0000844 void (*xDlClose)(sqlite3_vfs*, void*);
845 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
846 int (*xSleep)(sqlite3_vfs*, int microseconds);
847 int (*xCurrentTime)(sqlite3_vfs*, double*);
danielk1977bcb97fe2008-06-06 15:49:29 +0000848 int (*xGetLastError)(sqlite3_vfs*, int, char *);
drhf2424c52010-04-26 00:04:55 +0000849 /*
850 ** The methods above are in version 1 of the sqlite_vfs object
851 ** definition. Those that follow are added in version 2 or later
852 */
drhf2424c52010-04-26 00:04:55 +0000853 int (*xRename)(sqlite3_vfs*, const char *zOld, const char *zNew, int dirSync);
854 int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
855 /*
856 ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
857 ** New fields may be appended in figure versions. The iVersion
858 ** value will increment whenever this happens.
859 */
drh6d2069d2007-08-14 01:58:53 +0000860};
861
drh50d3f902007-08-27 21:10:36 +0000862/*
drhd68eee02009-12-11 03:44:18 +0000863** CAPI3REF: Flags for the xAccess VFS method
drh50d3f902007-08-27 21:10:36 +0000864**
drh032ca702008-12-10 11:44:30 +0000865** These integer constants can be used as the third parameter to
drhfb434032009-12-11 23:11:26 +0000866** the xAccess method of an [sqlite3_vfs] object. They determine
mihailim04bcc002008-06-22 10:21:27 +0000867** what kind of permissions the xAccess method is looking for.
drh032ca702008-12-10 11:44:30 +0000868** With SQLITE_ACCESS_EXISTS, the xAccess method
mihailim04bcc002008-06-22 10:21:27 +0000869** simply checks whether the file exists.
drh032ca702008-12-10 11:44:30 +0000870** With SQLITE_ACCESS_READWRITE, the xAccess method
mihailim04bcc002008-06-22 10:21:27 +0000871** checks whether the file is both readable and writable.
drh032ca702008-12-10 11:44:30 +0000872** With SQLITE_ACCESS_READ, the xAccess method
mihailim04bcc002008-06-22 10:21:27 +0000873** checks whether the file is readable.
drh50d3f902007-08-27 21:10:36 +0000874*/
danielk1977b4b47412007-08-17 15:53:36 +0000875#define SQLITE_ACCESS_EXISTS 0
876#define SQLITE_ACCESS_READWRITE 1
drh50d3f902007-08-27 21:10:36 +0000877#define SQLITE_ACCESS_READ 2
danielk1977b4b47412007-08-17 15:53:36 +0000878
drh6d2069d2007-08-14 01:58:53 +0000879/*
drhf2424c52010-04-26 00:04:55 +0000880** CAPI3REF: Flags for the xShmLock VFS method
881**
drh9beb1582010-04-28 17:21:33 +0000882** These integer constants define the various locking states that
drhccd13d12010-05-05 19:09:49 +0000883** an sqlite3_shm object can be in.
drhf2424c52010-04-26 00:04:55 +0000884*/
drh9beb1582010-04-28 17:21:33 +0000885#define SQLITE_SHM_UNLOCK 0
drh7b694402010-04-29 15:17:48 +0000886#define SQLITE_SHM_READ 1
drh9beb1582010-04-28 17:21:33 +0000887#define SQLITE_SHM_READ_FULL 2
888#define SQLITE_SHM_WRITE 3
889#define SQLITE_SHM_PENDING 4
890#define SQLITE_SHM_CHECKPOINT 5
891#define SQLITE_SHM_RECOVER 6
drhf2424c52010-04-26 00:04:55 +0000892
893/*
drhd68eee02009-12-11 03:44:18 +0000894** CAPI3REF: Initialize The SQLite Library
drh673299b2008-06-09 21:57:22 +0000895**
drhd68eee02009-12-11 03:44:18 +0000896** ^The sqlite3_initialize() routine initializes the
897** SQLite library. ^The sqlite3_shutdown() routine
drhcb041342008-06-12 00:07:29 +0000898** deallocates any resources that were allocated by sqlite3_initialize().
drh481aa742009-11-05 18:46:02 +0000899** These routines are designed to aid in process initialization and
drh9524f4b2009-10-20 15:27:55 +0000900** shutdown on embedded systems. Workstation applications using
901** SQLite normally do not need to invoke either of these routines.
drh673299b2008-06-09 21:57:22 +0000902**
drhcb041342008-06-12 00:07:29 +0000903** A call to sqlite3_initialize() is an "effective" call if it is
904** the first time sqlite3_initialize() is invoked during the lifetime of
905** the process, or if it is the first time sqlite3_initialize() is invoked
drhd68eee02009-12-11 03:44:18 +0000906** following a call to sqlite3_shutdown(). ^(Only an effective call
drhcb041342008-06-12 00:07:29 +0000907** of sqlite3_initialize() does any initialization. All other calls
drhd68eee02009-12-11 03:44:18 +0000908** are harmless no-ops.)^
drhcb041342008-06-12 00:07:29 +0000909**
drhd1a24402009-04-19 12:23:58 +0000910** A call to sqlite3_shutdown() is an "effective" call if it is the first
drhd68eee02009-12-11 03:44:18 +0000911** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
drhd1a24402009-04-19 12:23:58 +0000912** an effective call to sqlite3_shutdown() does any deinitialization.
drhd68eee02009-12-11 03:44:18 +0000913** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
drhd1a24402009-04-19 12:23:58 +0000914**
drh9524f4b2009-10-20 15:27:55 +0000915** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
916** is not. The sqlite3_shutdown() interface must only be called from a
917** single thread. All open [database connections] must be closed and all
918** other SQLite resources must be deallocated prior to invoking
919** sqlite3_shutdown().
920**
drhd68eee02009-12-11 03:44:18 +0000921** Among other things, ^sqlite3_initialize() will invoke
922** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
drh9524f4b2009-10-20 15:27:55 +0000923** will invoke sqlite3_os_end().
drh673299b2008-06-09 21:57:22 +0000924**
drhd68eee02009-12-11 03:44:18 +0000925** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
926** ^If for some reason, sqlite3_initialize() is unable to initialize
drhce5a5a02008-06-10 17:41:44 +0000927** the library (perhaps it is unable to allocate a needed resource such
drhadfae6c2008-10-10 17:26:35 +0000928** as a mutex) it returns an [error code] other than [SQLITE_OK].
drh673299b2008-06-09 21:57:22 +0000929**
drhd68eee02009-12-11 03:44:18 +0000930** ^The sqlite3_initialize() routine is called internally by many other
drhcb041342008-06-12 00:07:29 +0000931** SQLite interfaces so that an application usually does not need to
drhce5a5a02008-06-10 17:41:44 +0000932** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
933** calls sqlite3_initialize() so the SQLite library will be automatically
934** initialized when [sqlite3_open()] is called if it has not be initialized
drhd68eee02009-12-11 03:44:18 +0000935** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
drhcb041342008-06-12 00:07:29 +0000936** compile-time option, then the automatic calls to sqlite3_initialize()
937** are omitted and the application must call sqlite3_initialize() directly
938** prior to using any other SQLite interface. For maximum portability,
939** it is recommended that applications always invoke sqlite3_initialize()
940** directly prior to using any other SQLite interface. Future releases
941** of SQLite may require this. In other words, the behavior exhibited
drhadfae6c2008-10-10 17:26:35 +0000942** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
drhcb041342008-06-12 00:07:29 +0000943** default behavior in some future release of SQLite.
drh673299b2008-06-09 21:57:22 +0000944**
drhcb041342008-06-12 00:07:29 +0000945** The sqlite3_os_init() routine does operating-system specific
946** initialization of the SQLite library. The sqlite3_os_end()
947** routine undoes the effect of sqlite3_os_init(). Typical tasks
948** performed by these routines include allocation or deallocation
949** of static resources, initialization of global variables,
950** setting up a default [sqlite3_vfs] module, or setting up
mihailima3f64902008-06-21 13:35:56 +0000951** a default configuration using [sqlite3_config()].
drh673299b2008-06-09 21:57:22 +0000952**
drhcb041342008-06-12 00:07:29 +0000953** The application should never invoke either sqlite3_os_init()
954** or sqlite3_os_end() directly. The application should only invoke
955** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
mihailima3f64902008-06-21 13:35:56 +0000956** interface is called automatically by sqlite3_initialize() and
drhcb041342008-06-12 00:07:29 +0000957** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
958** implementations for sqlite3_os_init() and sqlite3_os_end()
shane7c7c3112009-08-17 15:31:23 +0000959** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
drh6aa5f152009-08-19 15:57:07 +0000960** When [custom builds | built for other platforms]
961** (using the [SQLITE_OS_OTHER=1] compile-time
drhcb041342008-06-12 00:07:29 +0000962** option) the application must supply a suitable implementation for
963** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
964** implementation of sqlite3_os_init() or sqlite3_os_end()
drhadfae6c2008-10-10 17:26:35 +0000965** must return [SQLITE_OK] on success and some other [error code] upon
drhcb041342008-06-12 00:07:29 +0000966** failure.
drh673299b2008-06-09 21:57:22 +0000967*/
drhce5a5a02008-06-10 17:41:44 +0000968int sqlite3_initialize(void);
drh673299b2008-06-09 21:57:22 +0000969int sqlite3_shutdown(void);
drhcb041342008-06-12 00:07:29 +0000970int sqlite3_os_init(void);
971int sqlite3_os_end(void);
drh673299b2008-06-09 21:57:22 +0000972
drhce5a5a02008-06-10 17:41:44 +0000973/*
drhd68eee02009-12-11 03:44:18 +0000974** CAPI3REF: Configuring The SQLite Library
drhce5a5a02008-06-10 17:41:44 +0000975**
976** The sqlite3_config() interface is used to make global configuration
977** changes to SQLite in order to tune SQLite to the specific needs of
978** the application. The default configuration is recommended for most
979** applications and so this routine is usually not necessary. It is
980** provided to support rare applications with unusual needs.
981**
982** The sqlite3_config() interface is not threadsafe. The application
983** must insure that no other SQLite interfaces are invoked by other
984** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
985** may only be invoked prior to library initialization using
986** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
drhd68eee02009-12-11 03:44:18 +0000987** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
988** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
989** Note, however, that ^sqlite3_config() can be called as part of the
drh40257ff2008-06-13 18:24:27 +0000990** implementation of an application-defined [sqlite3_os_init()].
drhce5a5a02008-06-10 17:41:44 +0000991**
992** The first argument to sqlite3_config() is an integer
993** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines
994** what property of SQLite is to be configured. Subsequent arguments
995** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option]
996** in the first argument.
997**
drhd68eee02009-12-11 03:44:18 +0000998** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
999** ^If the option is unknown or SQLite is unable to set the option
drh40257ff2008-06-13 18:24:27 +00001000** then this routine returns a non-zero [error code].
drhce5a5a02008-06-10 17:41:44 +00001001*/
drh9f8da322010-03-10 20:06:37 +00001002int sqlite3_config(int, ...);
drhce5a5a02008-06-10 17:41:44 +00001003
1004/*
drhd68eee02009-12-11 03:44:18 +00001005** CAPI3REF: Configure database connections
drh633e6d52008-07-28 19:34:53 +00001006**
1007** The sqlite3_db_config() interface is used to make configuration
drh2462e322008-07-31 14:47:54 +00001008** changes to a [database connection]. The interface is similar to
1009** [sqlite3_config()] except that the changes apply to a single
1010** [database connection] (specified in the first argument). The
drhd68eee02009-12-11 03:44:18 +00001011** sqlite3_db_config() interface should only be used immediately after
drh2462e322008-07-31 14:47:54 +00001012** the database connection is created using [sqlite3_open()],
1013** [sqlite3_open16()], or [sqlite3_open_v2()].
1014**
1015** The second argument to sqlite3_db_config(D,V,...) is the
1016** configuration verb - an integer code that indicates what
1017** aspect of the [database connection] is being configured.
drhe9d1c722008-08-04 20:13:26 +00001018** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
drh2462e322008-07-31 14:47:54 +00001019** New verbs are likely to be added in future releases of SQLite.
drhe9d1c722008-08-04 20:13:26 +00001020** Additional arguments depend on the verb.
drhf8cecda2008-10-10 23:48:25 +00001021**
drhd68eee02009-12-11 03:44:18 +00001022** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1023** the call is considered successful.
drh633e6d52008-07-28 19:34:53 +00001024*/
drh9f8da322010-03-10 20:06:37 +00001025int sqlite3_db_config(sqlite3*, int op, ...);
drh633e6d52008-07-28 19:34:53 +00001026
1027/*
drhfb434032009-12-11 23:11:26 +00001028** CAPI3REF: Memory Allocation Routines
drhfec00ea2008-06-14 16:56:21 +00001029**
1030** An instance of this object defines the interface between SQLite
mihailima3f64902008-06-21 13:35:56 +00001031** and low-level memory allocation routines.
drhfec00ea2008-06-14 16:56:21 +00001032**
1033** This object is used in only one place in the SQLite interface.
1034** A pointer to an instance of this object is the argument to
drh4766b292008-06-26 02:53:02 +00001035** [sqlite3_config()] when the configuration option is
drh6aa5f152009-08-19 15:57:07 +00001036** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1037** By creating an instance of this object
1038** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1039** during configuration, an application can specify an alternative
1040** memory allocation subsystem for SQLite to use for all of its
1041** dynamic memory needs.
drhfec00ea2008-06-14 16:56:21 +00001042**
drh6aa5f152009-08-19 15:57:07 +00001043** Note that SQLite comes with several [built-in memory allocators]
1044** that are perfectly adequate for the overwhelming majority of applications
drhfec00ea2008-06-14 16:56:21 +00001045** and that this object is only useful to a tiny minority of applications
1046** with specialized memory allocation requirements. This object is
1047** also used during testing of SQLite in order to specify an alternative
1048** memory allocator that simulates memory out-of-memory conditions in
1049** order to verify that SQLite recovers gracefully from such
1050** conditions.
1051**
drh6aa5f152009-08-19 15:57:07 +00001052** The xMalloc and xFree methods must work like the
1053** malloc() and free() functions from the standard C library.
1054** The xRealloc method must work like realloc() from the standard C library
1055** with the exception that if the second argument to xRealloc is zero,
1056** xRealloc must be a no-op - it must not perform any allocation or
drhd68eee02009-12-11 03:44:18 +00001057** deallocation. ^SQLite guarantees that the second argument to
drh6aa5f152009-08-19 15:57:07 +00001058** xRealloc is always a value returned by a prior call to xRoundup.
1059** And so in cases where xRoundup always returns a positive number,
1060** xRealloc can perform exactly as the standard library realloc() and
1061** still be in compliance with this specification.
drhfec00ea2008-06-14 16:56:21 +00001062**
1063** xSize should return the allocated size of a memory allocation
1064** previously obtained from xMalloc or xRealloc. The allocated size
1065** is always at least as big as the requested size but may be larger.
1066**
1067** The xRoundup method returns what would be the allocated size of
1068** a memory allocation given a particular requested size. Most memory
1069** allocators round up memory allocations at least to the next multiple
mihailima3f64902008-06-21 13:35:56 +00001070** of 8. Some allocators round up to a larger multiple or to a power of 2.
drh6aa5f152009-08-19 15:57:07 +00001071** Every memory allocation request coming in through [sqlite3_malloc()]
1072** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
1073** that causes the corresponding memory allocation to fail.
drhe5ae5732008-06-15 02:51:47 +00001074**
drhfec00ea2008-06-14 16:56:21 +00001075** The xInit method initializes the memory allocator. (For example,
1076** it might allocate any require mutexes or initialize internal data
1077** structures. The xShutdown method is invoked (indirectly) by
1078** [sqlite3_shutdown()] and should deallocate any resources acquired
1079** by xInit. The pAppData pointer is used as the only parameter to
1080** xInit and xShutdown.
drh9ac06502009-08-17 13:42:29 +00001081**
1082** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
1083** the xInit method, so the xInit method need not be threadsafe. The
1084** xShutdown method is only called from [sqlite3_shutdown()] so it does
drh6aa5f152009-08-19 15:57:07 +00001085** not need to be threadsafe either. For all other methods, SQLite
1086** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1087** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1088** it is by default) and so the methods are automatically serialized.
1089** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1090** methods must be threadsafe or else make their own arrangements for
1091** serialization.
drh9ac06502009-08-17 13:42:29 +00001092**
1093** SQLite will never invoke xInit() more than once without an intervening
1094** call to xShutdown().
drhfec00ea2008-06-14 16:56:21 +00001095*/
1096typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1097struct sqlite3_mem_methods {
1098 void *(*xMalloc)(int); /* Memory allocation function */
1099 void (*xFree)(void*); /* Free a prior allocation */
1100 void *(*xRealloc)(void*,int); /* Resize an allocation */
1101 int (*xSize)(void*); /* Return the size of an allocation */
1102 int (*xRoundup)(int); /* Round up request size to allocation size */
1103 int (*xInit)(void*); /* Initialize the memory allocator */
1104 void (*xShutdown)(void*); /* Deinitialize the memory allocator */
1105 void *pAppData; /* Argument to xInit() and xShutdown() */
1106};
1107
1108/*
drhfb434032009-12-11 23:11:26 +00001109** CAPI3REF: Configuration Options
drhce5a5a02008-06-10 17:41:44 +00001110**
1111** These constants are the available integer configuration options that
1112** can be passed as the first argument to the [sqlite3_config()] interface.
mihailima3f64902008-06-21 13:35:56 +00001113**
drha911abe2008-07-16 13:29:51 +00001114** New configuration options may be added in future releases of SQLite.
1115** Existing configuration options might be discontinued. Applications
1116** should check the return code from [sqlite3_config()] to make sure that
1117** the call worked. The [sqlite3_config()] interface will return a
1118** non-zero [error code] if a discontinued or unsupported configuration option
1119** is invoked.
1120**
drhce5a5a02008-06-10 17:41:44 +00001121** <dl>
1122** <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
drhd68eee02009-12-11 03:44:18 +00001123** <dd>There are no arguments to this option. ^This option sets the
1124** [threading mode] to Single-thread. In other words, it disables
drhce5a5a02008-06-10 17:41:44 +00001125** all mutexing and puts SQLite into a mode where it can only be used
drhd68eee02009-12-11 03:44:18 +00001126** by a single thread. ^If SQLite is compiled with
1127** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1128** it is not possible to change the [threading mode] from its default
1129** value of Single-thread and so [sqlite3_config()] will return
1130** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1131** configuration option.</dd>
drhce5a5a02008-06-10 17:41:44 +00001132**
1133** <dt>SQLITE_CONFIG_MULTITHREAD</dt>
drhd68eee02009-12-11 03:44:18 +00001134** <dd>There are no arguments to this option. ^This option sets the
1135** [threading mode] to Multi-thread. In other words, it disables
drhce5a5a02008-06-10 17:41:44 +00001136** mutexing on [database connection] and [prepared statement] objects.
1137** The application is responsible for serializing access to
1138** [database connections] and [prepared statements]. But other mutexes
1139** are enabled so that SQLite will be safe to use in a multi-threaded
drhafacce02008-09-02 21:35:03 +00001140** environment as long as no two threads attempt to use the same
drhd68eee02009-12-11 03:44:18 +00001141** [database connection] at the same time. ^If SQLite is compiled with
1142** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1143** it is not possible to set the Multi-thread [threading mode] and
1144** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1145** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
drhce5a5a02008-06-10 17:41:44 +00001146**
1147** <dt>SQLITE_CONFIG_SERIALIZED</dt>
drhd68eee02009-12-11 03:44:18 +00001148** <dd>There are no arguments to this option. ^This option sets the
1149** [threading mode] to Serialized. In other words, this option enables
drhce5a5a02008-06-10 17:41:44 +00001150** all mutexes including the recursive
1151** mutexes on [database connection] and [prepared statement] objects.
1152** In this mode (which is the default when SQLite is compiled with
drh4766b292008-06-26 02:53:02 +00001153** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
drhce5a5a02008-06-10 17:41:44 +00001154** to [database connections] and [prepared statements] so that the
1155** application is free to use the same [database connection] or the
drh31d38cf2008-07-12 20:35:08 +00001156** same [prepared statement] in different threads at the same time.
drhd68eee02009-12-11 03:44:18 +00001157** ^If SQLite is compiled with
1158** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1159** it is not possible to set the Serialized [threading mode] and
1160** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1161** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
drhce5a5a02008-06-10 17:41:44 +00001162**
1163** <dt>SQLITE_CONFIG_MALLOC</dt>
drhd68eee02009-12-11 03:44:18 +00001164** <dd> ^(This option takes a single argument which is a pointer to an
mihailimdb4f2ad2008-06-21 11:20:48 +00001165** instance of the [sqlite3_mem_methods] structure. The argument specifies
1166** alternative low-level memory allocation routines to be used in place of
drhd68eee02009-12-11 03:44:18 +00001167** the memory allocation routines built into SQLite.)^ ^SQLite makes
1168** its own private copy of the content of the [sqlite3_mem_methods] structure
1169** before the [sqlite3_config()] call returns.</dd>
drhce5a5a02008-06-10 17:41:44 +00001170**
drh33589792008-06-18 13:27:46 +00001171** <dt>SQLITE_CONFIG_GETMALLOC</dt>
drhd68eee02009-12-11 03:44:18 +00001172** <dd> ^(This option takes a single argument which is a pointer to an
drh33589792008-06-18 13:27:46 +00001173** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods]
drhd68eee02009-12-11 03:44:18 +00001174** structure is filled with the currently defined memory allocation routines.)^
drh33589792008-06-18 13:27:46 +00001175** This option can be used to overload the default memory allocation
1176** routines with a wrapper that simulations memory allocation failure or
drhd68eee02009-12-11 03:44:18 +00001177** tracks memory usage, for example. </dd>
drh33589792008-06-18 13:27:46 +00001178**
drhfec00ea2008-06-14 16:56:21 +00001179** <dt>SQLITE_CONFIG_MEMSTATUS</dt>
drhd68eee02009-12-11 03:44:18 +00001180** <dd> ^This option takes single argument of type int, interpreted as a
danielk197795c232d2008-07-28 05:22:35 +00001181** boolean, which enables or disables the collection of memory allocation
drhd68eee02009-12-11 03:44:18 +00001182** statistics. ^(When memory allocation statistics are disabled, the
1183** following SQLite interfaces become non-operational:
drhce5a5a02008-06-10 17:41:44 +00001184** <ul>
1185** <li> [sqlite3_memory_used()]
1186** <li> [sqlite3_memory_highwater()]
1187** <li> [sqlite3_soft_heap_limit()]
drh0a60a382008-07-31 17:16:05 +00001188** <li> [sqlite3_status()]
drhd68eee02009-12-11 03:44:18 +00001189** </ul>)^
1190** ^Memory allocation statistics are enabled by default unless SQLite is
1191** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1192** allocation statistics are disabled by default.
drhce5a5a02008-06-10 17:41:44 +00001193** </dd>
drh33589792008-06-18 13:27:46 +00001194**
1195** <dt>SQLITE_CONFIG_SCRATCH</dt>
drhd68eee02009-12-11 03:44:18 +00001196** <dd> ^This option specifies a static memory buffer that SQLite can use for
drh6860da02009-06-09 19:53:58 +00001197** scratch memory. There are three arguments: A pointer an 8-byte
1198** aligned memory buffer from which the scrach allocations will be
1199** drawn, the size of each scratch allocation (sz),
1200** and the maximum number of scratch allocations (N). The sz
drh0a60a382008-07-31 17:16:05 +00001201** argument must be a multiple of 16. The sz parameter should be a few bytes
drh6860da02009-06-09 19:53:58 +00001202** larger than the actual scratch space required due to internal overhead.
drhd68eee02009-12-11 03:44:18 +00001203** The first argument must be a pointer to an 8-byte aligned buffer
drh6860da02009-06-09 19:53:58 +00001204** of at least sz*N bytes of memory.
drhd68eee02009-12-11 03:44:18 +00001205** ^SQLite will use no more than one scratch buffer per thread. So
1206** N should be set to the expected maximum number of threads. ^SQLite will
1207** never require a scratch buffer that is more than 6 times the database
1208** page size. ^If SQLite needs needs additional scratch memory beyond
1209** what is provided by this configuration option, then
1210** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
drh33589792008-06-18 13:27:46 +00001211**
1212** <dt>SQLITE_CONFIG_PAGECACHE</dt>
drhd68eee02009-12-11 03:44:18 +00001213** <dd> ^This option specifies a static memory buffer that SQLite can use for
drh21614742008-11-18 19:18:08 +00001214** the database page cache with the default page cache implemenation.
1215** This configuration should not be used if an application-define page
1216** cache implementation is loaded using the SQLITE_CONFIG_PCACHE option.
drh6860da02009-06-09 19:53:58 +00001217** There are three arguments to this option: A pointer to 8-byte aligned
mihailimdb4f2ad2008-06-21 11:20:48 +00001218** memory, the size of each page buffer (sz), and the number of pages (N).
drh6860da02009-06-09 19:53:58 +00001219** The sz argument should be the size of the largest database page
1220** (a power of two between 512 and 32768) plus a little extra for each
drhd68eee02009-12-11 03:44:18 +00001221** page header. ^The page header size is 20 to 40 bytes depending on
1222** the host architecture. ^It is harmless, apart from the wasted memory,
drh6860da02009-06-09 19:53:58 +00001223** to make sz a little too large. The first
drh0a60a382008-07-31 17:16:05 +00001224** argument should point to an allocation of at least sz*N bytes of memory.
drhd68eee02009-12-11 03:44:18 +00001225** ^SQLite will use the memory provided by the first argument to satisfy its
1226** memory needs for the first N pages that it adds to cache. ^If additional
mihailimdb4f2ad2008-06-21 11:20:48 +00001227** page cache memory is needed beyond what is provided by this option, then
drh0a60a382008-07-31 17:16:05 +00001228** SQLite goes to [sqlite3_malloc()] for the additional storage space.
drhd68eee02009-12-11 03:44:18 +00001229** ^The implementation might use one or more of the N buffers to hold
drh6860da02009-06-09 19:53:58 +00001230** memory accounting information. The pointer in the first argument must
1231** be aligned to an 8-byte boundary or subsequent behavior of SQLite
1232** will be undefined.</dd>
drh33589792008-06-18 13:27:46 +00001233**
1234** <dt>SQLITE_CONFIG_HEAP</dt>
drhd68eee02009-12-11 03:44:18 +00001235** <dd> ^This option specifies a static memory buffer that SQLite will use
drh33589792008-06-18 13:27:46 +00001236** for all of its dynamic memory allocation needs beyond those provided
1237** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
drh6860da02009-06-09 19:53:58 +00001238** There are three arguments: An 8-byte aligned pointer to the memory,
1239** the number of bytes in the memory buffer, and the minimum allocation size.
drhd68eee02009-12-11 03:44:18 +00001240** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
drh8a42cbd2008-07-10 18:13:42 +00001241** to using its default memory allocator (the system malloc() implementation),
drhd68eee02009-12-11 03:44:18 +00001242** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
drh8a42cbd2008-07-10 18:13:42 +00001243** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
1244** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
drh39bf74a2009-06-09 18:02:10 +00001245** allocator is engaged to handle all of SQLites memory allocation needs.
1246** The first pointer (the memory pointer) must be aligned to an 8-byte
drh6860da02009-06-09 19:53:58 +00001247** boundary or subsequent behavior of SQLite will be undefined.</dd>
drh33589792008-06-18 13:27:46 +00001248**
1249** <dt>SQLITE_CONFIG_MUTEX</dt>
drhd68eee02009-12-11 03:44:18 +00001250** <dd> ^(This option takes a single argument which is a pointer to an
mihailimdb4f2ad2008-06-21 11:20:48 +00001251** instance of the [sqlite3_mutex_methods] structure. The argument specifies
drh33589792008-06-18 13:27:46 +00001252** alternative low-level mutex routines to be used in place
drhd68eee02009-12-11 03:44:18 +00001253** the mutex routines built into SQLite.)^ ^SQLite makes a copy of the
1254** content of the [sqlite3_mutex_methods] structure before the call to
1255** [sqlite3_config()] returns. ^If SQLite is compiled with
1256** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1257** the entire mutexing subsystem is omitted from the build and hence calls to
1258** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1259** return [SQLITE_ERROR].</dd>
drh33589792008-06-18 13:27:46 +00001260**
drh584ff182008-07-14 18:38:17 +00001261** <dt>SQLITE_CONFIG_GETMUTEX</dt>
drhd68eee02009-12-11 03:44:18 +00001262** <dd> ^(This option takes a single argument which is a pointer to an
drh33589792008-06-18 13:27:46 +00001263** instance of the [sqlite3_mutex_methods] structure. The
1264** [sqlite3_mutex_methods]
drhd68eee02009-12-11 03:44:18 +00001265** structure is filled with the currently defined mutex routines.)^
drh33589792008-06-18 13:27:46 +00001266** This option can be used to overload the default mutex allocation
1267** routines with a wrapper used to track mutex usage for performance
drhd68eee02009-12-11 03:44:18 +00001268** profiling or testing, for example. ^If SQLite is compiled with
1269** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1270** the entire mutexing subsystem is omitted from the build and hence calls to
1271** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1272** return [SQLITE_ERROR].</dd>
drh633e6d52008-07-28 19:34:53 +00001273**
1274** <dt>SQLITE_CONFIG_LOOKASIDE</dt>
drhd68eee02009-12-11 03:44:18 +00001275** <dd> ^(This option takes two arguments that determine the default
drh9be37f62009-12-12 23:57:36 +00001276** memory allocation for the lookaside memory allocator on each
1277** [database connection]. The first argument is the
drh633e6d52008-07-28 19:34:53 +00001278** size of each lookaside buffer slot and the second is the number of
drhd68eee02009-12-11 03:44:18 +00001279** slots allocated to each database connection.)^ ^(This option sets the
1280** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
drh6aa5f152009-08-19 15:57:07 +00001281** verb to [sqlite3_db_config()] can be used to change the lookaside
drhd68eee02009-12-11 03:44:18 +00001282** configuration on individual connections.)^ </dd>
drh633e6d52008-07-28 19:34:53 +00001283**
drh21614742008-11-18 19:18:08 +00001284** <dt>SQLITE_CONFIG_PCACHE</dt>
drhd68eee02009-12-11 03:44:18 +00001285** <dd> ^(This option takes a single argument which is a pointer to
drh21614742008-11-18 19:18:08 +00001286** an [sqlite3_pcache_methods] object. This object specifies the interface
drhd68eee02009-12-11 03:44:18 +00001287** to a custom page cache implementation.)^ ^SQLite makes a copy of the
drh21614742008-11-18 19:18:08 +00001288** object and uses it for page cache memory allocations.</dd>
1289**
1290** <dt>SQLITE_CONFIG_GETPCACHE</dt>
drhd68eee02009-12-11 03:44:18 +00001291** <dd> ^(This option takes a single argument which is a pointer to an
drh21614742008-11-18 19:18:08 +00001292** [sqlite3_pcache_methods] object. SQLite copies of the current
drhd68eee02009-12-11 03:44:18 +00001293** page cache implementation into that object.)^ </dd>
drh21614742008-11-18 19:18:08 +00001294**
drhd3d986d2010-03-31 13:57:56 +00001295** <dt>SQLITE_CONFIG_LOG</dt>
1296** <dd> ^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1297** function with a call signature of void(*)(void*,int,const char*),
1298** and a pointer to void. ^If the function pointer is not NULL, it is
1299** invoked by [sqlite3_log()] to process each logging event. ^If the
1300** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
1301** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
1302** passed through as the first parameter to the application-defined logger
1303** function whenever that function is invoked. ^The second parameter to
1304** the logger function is a copy of the first parameter to the corresponding
1305** [sqlite3_log()] call and is intended to be a [result code] or an
1306** [extended result code]. ^The third parameter passed to the logger is
1307** log message after formatting via [sqlite3_snprintf()].
1308** The SQLite logging interface is not reentrant; the logger function
1309** supplied by the application must not invoke any SQLite interface.
1310** In a multi-threaded application, the application-defined logger
1311** function must be threadsafe. </dd>
1312**
drh633e6d52008-07-28 19:34:53 +00001313** </dl>
mihailima3f64902008-06-21 13:35:56 +00001314*/
drh40257ff2008-06-13 18:24:27 +00001315#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
1316#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
1317#define SQLITE_CONFIG_SERIALIZED 3 /* nil */
drhfec00ea2008-06-14 16:56:21 +00001318#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
drh33589792008-06-18 13:27:46 +00001319#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
1320#define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
1321#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
1322#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
1323#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
1324#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
1325#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
shane2479de32008-11-10 18:05:35 +00001326/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
drh633e6d52008-07-28 19:34:53 +00001327#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
danielk1977bc2ca9e2008-11-13 14:28:28 +00001328#define SQLITE_CONFIG_PCACHE 14 /* sqlite3_pcache_methods* */
1329#define SQLITE_CONFIG_GETPCACHE 15 /* sqlite3_pcache_methods* */
drh3f280702010-02-18 18:45:09 +00001330#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
danielk19772d340812008-07-24 08:20:40 +00001331
drhe9d1c722008-08-04 20:13:26 +00001332/*
drh9f8da322010-03-10 20:06:37 +00001333** CAPI3REF: Database Connection Configuration Options
drhe9d1c722008-08-04 20:13:26 +00001334**
1335** These constants are the available integer configuration options that
1336** can be passed as the second argument to the [sqlite3_db_config()] interface.
1337**
1338** New configuration options may be added in future releases of SQLite.
1339** Existing configuration options might be discontinued. Applications
1340** should check the return code from [sqlite3_db_config()] to make sure that
drhd68eee02009-12-11 03:44:18 +00001341** the call worked. ^The [sqlite3_db_config()] interface will return a
drhe9d1c722008-08-04 20:13:26 +00001342** non-zero [error code] if a discontinued or unsupported configuration option
1343** is invoked.
1344**
1345** <dl>
1346** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
drhd68eee02009-12-11 03:44:18 +00001347** <dd> ^This option takes three additional arguments that determine the
drhe9d1c722008-08-04 20:13:26 +00001348** [lookaside memory allocator] configuration for the [database connection].
drhd68eee02009-12-11 03:44:18 +00001349** ^The first argument (the third parameter to [sqlite3_db_config()] is a
drh6aa5f152009-08-19 15:57:07 +00001350** pointer to an memory buffer to use for lookaside memory.
drhd68eee02009-12-11 03:44:18 +00001351** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
1352** may be NULL in which case SQLite will allocate the
1353** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
1354** size of each lookaside buffer slot. ^The third argument is the number of
drhe9d1c722008-08-04 20:13:26 +00001355** slots. The size of the buffer in the first argument must be greater than
drh6aa5f152009-08-19 15:57:07 +00001356** or equal to the product of the second and third arguments. The buffer
drhd68eee02009-12-11 03:44:18 +00001357** must be aligned to an 8-byte boundary. ^If the second argument to
1358** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
1359** rounded down to the next smaller
drh6aa5f152009-08-19 15:57:07 +00001360** multiple of 8. See also: [SQLITE_CONFIG_LOOKASIDE]</dd>
drhe9d1c722008-08-04 20:13:26 +00001361**
1362** </dl>
1363*/
1364#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
1365
drhce5a5a02008-06-10 17:41:44 +00001366
drh673299b2008-06-09 21:57:22 +00001367/*
drhd68eee02009-12-11 03:44:18 +00001368** CAPI3REF: Enable Or Disable Extended Result Codes
drh6ed48bf2007-06-14 20:57:18 +00001369**
drhd68eee02009-12-11 03:44:18 +00001370** ^The sqlite3_extended_result_codes() routine enables or disables the
1371** [extended result codes] feature of SQLite. ^The extended result
1372** codes are disabled by default for historical compatibility.
drh4ac285a2006-09-15 07:28:50 +00001373*/
1374int sqlite3_extended_result_codes(sqlite3*, int onoff);
1375
1376/*
drhd68eee02009-12-11 03:44:18 +00001377** CAPI3REF: Last Insert Rowid
drh6ed48bf2007-06-14 20:57:18 +00001378**
drhd68eee02009-12-11 03:44:18 +00001379** ^Each entry in an SQLite table has a unique 64-bit signed
1380** integer key called the [ROWID | "rowid"]. ^The rowid is always available
drhfddfa2d2007-12-05 18:05:16 +00001381** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
drhd68eee02009-12-11 03:44:18 +00001382** names are not also used by explicitly declared columns. ^If
drh49c3d572008-12-15 22:51:38 +00001383** the table has a column of type [INTEGER PRIMARY KEY] then that column
mlcreechb2799412008-03-07 03:20:31 +00001384** is another alias for the rowid.
drh6ed48bf2007-06-14 20:57:18 +00001385**
drhd68eee02009-12-11 03:44:18 +00001386** ^This routine returns the [rowid] of the most recent
drhf8cecda2008-10-10 23:48:25 +00001387** successful [INSERT] into the database from the [database connection]
drhd68eee02009-12-11 03:44:18 +00001388** in the first argument. ^If no successful [INSERT]s
mihailimdb4f2ad2008-06-21 11:20:48 +00001389** have ever occurred on that database connection, zero is returned.
drh6ed48bf2007-06-14 20:57:18 +00001390**
drhd68eee02009-12-11 03:44:18 +00001391** ^(If an [INSERT] occurs within a trigger, then the [rowid] of the inserted
mihailimdb4f2ad2008-06-21 11:20:48 +00001392** row is returned by this routine as long as the trigger is running.
1393** But once the trigger terminates, the value returned by this routine
drhd68eee02009-12-11 03:44:18 +00001394** reverts to the last value inserted before the trigger fired.)^
drhe30f4422007-08-21 16:15:55 +00001395**
drhd68eee02009-12-11 03:44:18 +00001396** ^An [INSERT] that fails due to a constraint violation is not a
drhf8cecda2008-10-10 23:48:25 +00001397** successful [INSERT] and does not change the value returned by this
drhd68eee02009-12-11 03:44:18 +00001398** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
drhdc1d9f12007-10-27 16:25:16 +00001399** and INSERT OR ABORT make no changes to the return value of this
drhd68eee02009-12-11 03:44:18 +00001400** routine when their insertion fails. ^(When INSERT OR REPLACE
drhdc1d9f12007-10-27 16:25:16 +00001401** encounters a constraint violation, it does not fail. The
1402** INSERT continues to completion after deleting rows that caused
1403** the constraint problem so INSERT OR REPLACE will always change
drhd68eee02009-12-11 03:44:18 +00001404** the return value of this interface.)^
drhdc1d9f12007-10-27 16:25:16 +00001405**
drhd68eee02009-12-11 03:44:18 +00001406** ^For the purposes of this routine, an [INSERT] is considered to
drh33c1be32008-01-30 16:16:14 +00001407** be successful even if it is subsequently rolled back.
1408**
drha94cc422009-12-03 01:01:02 +00001409** This function is accessible to SQL statements via the
1410** [last_insert_rowid() SQL function].
1411**
drh8b39db12009-02-18 18:37:58 +00001412** If a separate thread performs a new [INSERT] on the same
1413** database connection while the [sqlite3_last_insert_rowid()]
1414** function is running and thus changes the last insert [rowid],
1415** then the value returned by [sqlite3_last_insert_rowid()] is
1416** unpredictable and might not equal either the old or the new
1417** last insert [rowid].
drhaf9ff332002-01-16 21:00:27 +00001418*/
drh6d2069d2007-08-14 01:58:53 +00001419sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
drhaf9ff332002-01-16 21:00:27 +00001420
drhc8d30ac2002-04-12 10:08:59 +00001421/*
drhd68eee02009-12-11 03:44:18 +00001422** CAPI3REF: Count The Number Of Rows Modified
drh6ed48bf2007-06-14 20:57:18 +00001423**
drhd68eee02009-12-11 03:44:18 +00001424** ^This function returns the number of database rows that were changed
drhfddfa2d2007-12-05 18:05:16 +00001425** or inserted or deleted by the most recently completed SQL statement
mihailimdb4f2ad2008-06-21 11:20:48 +00001426** on the [database connection] specified by the first parameter.
drhd68eee02009-12-11 03:44:18 +00001427** ^(Only changes that are directly specified by the [INSERT], [UPDATE],
drhf8cecda2008-10-10 23:48:25 +00001428** or [DELETE] statement are counted. Auxiliary changes caused by
drhd68eee02009-12-11 03:44:18 +00001429** triggers or [foreign key actions] are not counted.)^ Use the
danb6163092009-10-07 10:43:26 +00001430** [sqlite3_total_changes()] function to find the total number of changes
1431** including changes caused by triggers and foreign key actions.
drh6ed48bf2007-06-14 20:57:18 +00001432**
drhd68eee02009-12-11 03:44:18 +00001433** ^Changes to a view that are simulated by an [INSTEAD OF trigger]
drhd9c20d72009-04-29 14:33:44 +00001434** are not counted. Only real table changes are counted.
1435**
drhd68eee02009-12-11 03:44:18 +00001436** ^(A "row change" is a change to a single row of a single table
drh33c1be32008-01-30 16:16:14 +00001437** caused by an INSERT, DELETE, or UPDATE statement. Rows that
drhd9c20d72009-04-29 14:33:44 +00001438** are changed as side effects of [REPLACE] constraint resolution,
1439** rollback, ABORT processing, [DROP TABLE], or by any other
drhd68eee02009-12-11 03:44:18 +00001440** mechanisms do not count as direct row changes.)^
drh33c1be32008-01-30 16:16:14 +00001441**
1442** A "trigger context" is a scope of execution that begins and
drhd9c20d72009-04-29 14:33:44 +00001443** ends with the script of a [CREATE TRIGGER | trigger].
1444** Most SQL statements are
drh33c1be32008-01-30 16:16:14 +00001445** evaluated outside of any trigger. This is the "top level"
1446** trigger context. If a trigger fires from the top level, a
1447** new trigger context is entered for the duration of that one
1448** trigger. Subtriggers create subcontexts for their duration.
1449**
drhd68eee02009-12-11 03:44:18 +00001450** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
drh33c1be32008-01-30 16:16:14 +00001451** not create a new trigger context.
1452**
drhd68eee02009-12-11 03:44:18 +00001453** ^This function returns the number of direct row changes in the
drh33c1be32008-01-30 16:16:14 +00001454** most recent INSERT, UPDATE, or DELETE statement within the same
1455** trigger context.
1456**
drhd68eee02009-12-11 03:44:18 +00001457** ^Thus, when called from the top level, this function returns the
drh33c1be32008-01-30 16:16:14 +00001458** number of changes in the most recent INSERT, UPDATE, or DELETE
drhd68eee02009-12-11 03:44:18 +00001459** that also occurred at the top level. ^(Within the body of a trigger,
mihailimdb4f2ad2008-06-21 11:20:48 +00001460** the sqlite3_changes() interface can be called to find the number of
drh930cc582007-03-28 13:07:40 +00001461** changes in the most recently completed INSERT, UPDATE, or DELETE
drhf5befa02007-12-06 02:42:07 +00001462** statement within the body of the same trigger.
mihailimdb4f2ad2008-06-21 11:20:48 +00001463** However, the number returned does not include changes
drhd68eee02009-12-11 03:44:18 +00001464** caused by subtriggers since those have their own context.)^
drhc8d30ac2002-04-12 10:08:59 +00001465**
drha94cc422009-12-03 01:01:02 +00001466** See also the [sqlite3_total_changes()] interface, the
1467** [count_changes pragma], and the [changes() SQL function].
drhe30f4422007-08-21 16:15:55 +00001468**
drh8b39db12009-02-18 18:37:58 +00001469** If a separate thread makes changes on the same database connection
1470** while [sqlite3_changes()] is running then the value returned
1471** is unpredictable and not meaningful.
drhc8d30ac2002-04-12 10:08:59 +00001472*/
danielk1977f9d64d22004-06-19 08:18:07 +00001473int sqlite3_changes(sqlite3*);
drhc8d30ac2002-04-12 10:08:59 +00001474
rdcf146a772004-02-25 22:51:06 +00001475/*
drhd68eee02009-12-11 03:44:18 +00001476** CAPI3REF: Total Number Of Rows Modified
mihailimdb4f2ad2008-06-21 11:20:48 +00001477**
drhd68eee02009-12-11 03:44:18 +00001478** ^This function returns the number of row changes caused by [INSERT],
drhd9c20d72009-04-29 14:33:44 +00001479** [UPDATE] or [DELETE] statements since the [database connection] was opened.
drhd68eee02009-12-11 03:44:18 +00001480** ^(The count returned by sqlite3_total_changes() includes all changes
1481** from all [CREATE TRIGGER | trigger] contexts and changes made by
1482** [foreign key actions]. However,
drhd9c20d72009-04-29 14:33:44 +00001483** the count does not include changes used to implement [REPLACE] constraints,
1484** do rollbacks or ABORT processing, or [DROP TABLE] processing. The
drh4fb08662009-05-22 01:02:26 +00001485** count does not include rows of views that fire an [INSTEAD OF trigger],
1486** though if the INSTEAD OF trigger makes changes of its own, those changes
drhd68eee02009-12-11 03:44:18 +00001487** are counted.)^
1488** ^The sqlite3_total_changes() function counts the changes as soon as
1489** the statement that makes them is completed (when the statement handle
1490** is passed to [sqlite3_reset()] or [sqlite3_finalize()]).
drh6ed48bf2007-06-14 20:57:18 +00001491**
drha94cc422009-12-03 01:01:02 +00001492** See also the [sqlite3_changes()] interface, the
1493** [count_changes pragma], and the [total_changes() SQL function].
drh33c1be32008-01-30 16:16:14 +00001494**
drh8b39db12009-02-18 18:37:58 +00001495** If a separate thread makes changes on the same database connection
1496** while [sqlite3_total_changes()] is running then the value
1497** returned is unpredictable and not meaningful.
rdcf146a772004-02-25 22:51:06 +00001498*/
danielk1977b28af712004-06-21 06:50:26 +00001499int sqlite3_total_changes(sqlite3*);
1500
drh6ed48bf2007-06-14 20:57:18 +00001501/*
drhd68eee02009-12-11 03:44:18 +00001502** CAPI3REF: Interrupt A Long-Running Query
drh6ed48bf2007-06-14 20:57:18 +00001503**
drhd68eee02009-12-11 03:44:18 +00001504** ^This function causes any pending database operation to abort and
drh33c1be32008-01-30 16:16:14 +00001505** return at its earliest opportunity. This routine is typically
mihailimebe796c2008-06-21 20:11:17 +00001506** called in response to a user action such as pressing "Cancel"
drh4c504392000-10-16 22:06:40 +00001507** or Ctrl-C where the user wants a long query operation to halt
1508** immediately.
drh930cc582007-03-28 13:07:40 +00001509**
drhd68eee02009-12-11 03:44:18 +00001510** ^It is safe to call this routine from a thread different from the
drh33c1be32008-01-30 16:16:14 +00001511** thread that is currently running the database operation. But it
mihailimdb4f2ad2008-06-21 11:20:48 +00001512** is not safe to call this routine with a [database connection] that
drh871f6ca2007-08-14 18:03:14 +00001513** is closed or might close before sqlite3_interrupt() returns.
drh6ed48bf2007-06-14 20:57:18 +00001514**
drhd68eee02009-12-11 03:44:18 +00001515** ^If an SQL operation is very nearly finished at the time when
mihailimdb4f2ad2008-06-21 11:20:48 +00001516** sqlite3_interrupt() is called, then it might not have an opportunity
1517** to be interrupted and might continue to completion.
1518**
drhd68eee02009-12-11 03:44:18 +00001519** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
1520** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
mihailimdb4f2ad2008-06-21 11:20:48 +00001521** that is inside an explicit transaction, then the entire transaction
1522** will be rolled back automatically.
1523**
drhdf6473a2009-12-13 22:20:08 +00001524** ^The sqlite3_interrupt(D) call is in effect until all currently running
1525** SQL statements on [database connection] D complete. ^Any new SQL statements
drhd2b68432009-04-20 12:31:46 +00001526** that are started after the sqlite3_interrupt() call and before the
1527** running statements reaches zero are interrupted as if they had been
drhdf6473a2009-12-13 22:20:08 +00001528** running prior to the sqlite3_interrupt() call. ^New SQL statements
drhd2b68432009-04-20 12:31:46 +00001529** that are started after the running statement count reaches zero are
drhdf6473a2009-12-13 22:20:08 +00001530** not effected by the sqlite3_interrupt().
drhd68eee02009-12-11 03:44:18 +00001531** ^A call to sqlite3_interrupt(D) that occurs when there are no running
drhd2b68432009-04-20 12:31:46 +00001532** SQL statements is a no-op and has no effect on SQL statements
1533** that are started after the sqlite3_interrupt() call returns.
drh33c1be32008-01-30 16:16:14 +00001534**
drh8b39db12009-02-18 18:37:58 +00001535** If the database connection closes while [sqlite3_interrupt()]
1536** is running then bad things will likely happen.
drh4c504392000-10-16 22:06:40 +00001537*/
danielk1977f9d64d22004-06-19 08:18:07 +00001538void sqlite3_interrupt(sqlite3*);
drh4c504392000-10-16 22:06:40 +00001539
drh6ed48bf2007-06-14 20:57:18 +00001540/*
drhd68eee02009-12-11 03:44:18 +00001541** CAPI3REF: Determine If An SQL Statement Is Complete
drh75897232000-05-29 14:26:00 +00001542**
drh709915d2009-04-28 04:46:41 +00001543** These routines are useful during command-line input to determine if the
1544** currently entered text seems to form a complete SQL statement or
drhf5befa02007-12-06 02:42:07 +00001545** if additional input is needed before sending the text into
drhd68eee02009-12-11 03:44:18 +00001546** SQLite for parsing. ^These routines return 1 if the input string
1547** appears to be a complete SQL statement. ^A statement is judged to be
drh709915d2009-04-28 04:46:41 +00001548** complete if it ends with a semicolon token and is not a prefix of a
drhd68eee02009-12-11 03:44:18 +00001549** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
drh33c1be32008-01-30 16:16:14 +00001550** string literals or quoted identifier names or comments are not
1551** independent tokens (they are part of the token in which they are
drhd68eee02009-12-11 03:44:18 +00001552** embedded) and thus do not count as a statement terminator. ^Whitespace
drh709915d2009-04-28 04:46:41 +00001553** and comments that follow the final semicolon are ignored.
1554**
drhd68eee02009-12-11 03:44:18 +00001555** ^These routines return 0 if the statement is incomplete. ^If a
drh709915d2009-04-28 04:46:41 +00001556** memory allocation fails, then SQLITE_NOMEM is returned.
drh33c1be32008-01-30 16:16:14 +00001557**
drhd68eee02009-12-11 03:44:18 +00001558** ^These routines do not parse the SQL statements thus
mihailimdb4f2ad2008-06-21 11:20:48 +00001559** will not detect syntactically incorrect SQL.
drhfddfa2d2007-12-05 18:05:16 +00001560**
drhd68eee02009-12-11 03:44:18 +00001561** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
drh709915d2009-04-28 04:46:41 +00001562** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
1563** automatically by sqlite3_complete16(). If that initialization fails,
1564** then the return value from sqlite3_complete16() will be non-zero
drhd68eee02009-12-11 03:44:18 +00001565** regardless of whether or not the input SQL is complete.)^
drh33c1be32008-01-30 16:16:14 +00001566**
drh8b39db12009-02-18 18:37:58 +00001567** The input to [sqlite3_complete()] must be a zero-terminated
1568** UTF-8 string.
drh33c1be32008-01-30 16:16:14 +00001569**
drh8b39db12009-02-18 18:37:58 +00001570** The input to [sqlite3_complete16()] must be a zero-terminated
1571** UTF-16 string in native byte order.
drh75897232000-05-29 14:26:00 +00001572*/
danielk19776f8a5032004-05-10 10:34:51 +00001573int sqlite3_complete(const char *sql);
danielk197761de0d12004-05-27 23:56:16 +00001574int sqlite3_complete16(const void *sql);
drh75897232000-05-29 14:26:00 +00001575
drh2dfbbca2000-07-28 14:32:48 +00001576/*
drhd68eee02009-12-11 03:44:18 +00001577** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
drh6ed48bf2007-06-14 20:57:18 +00001578**
drhd68eee02009-12-11 03:44:18 +00001579** ^This routine sets a callback function that might be invoked whenever
mihailimdb4f2ad2008-06-21 11:20:48 +00001580** an attempt is made to open a database table that another thread
1581** or process has locked.
1582**
drhd68eee02009-12-11 03:44:18 +00001583** ^If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
1584** is returned immediately upon encountering the lock. ^If the busy callback
1585** is not NULL, then the callback might be invoked with two arguments.
mihailimdb4f2ad2008-06-21 11:20:48 +00001586**
drhd68eee02009-12-11 03:44:18 +00001587** ^The first argument to the busy handler is a copy of the void* pointer which
1588** is the third argument to sqlite3_busy_handler(). ^The second argument to
1589** the busy handler callback is the number of times that the busy handler has
1590** been invoked for this locking event. ^If the
drh6ed48bf2007-06-14 20:57:18 +00001591** busy callback returns 0, then no additional attempts are made to
1592** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
drhd68eee02009-12-11 03:44:18 +00001593** ^If the callback returns non-zero, then another attempt
drhfddfa2d2007-12-05 18:05:16 +00001594** is made to open the database for reading and the cycle repeats.
drh2dfbbca2000-07-28 14:32:48 +00001595**
mihailimdb4f2ad2008-06-21 11:20:48 +00001596** The presence of a busy handler does not guarantee that it will be invoked
drhd68eee02009-12-11 03:44:18 +00001597** when there is lock contention. ^If SQLite determines that invoking the busy
mihailimdb4f2ad2008-06-21 11:20:48 +00001598** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
1599** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
drh86939b52007-01-10 12:54:51 +00001600** Consider a scenario where one process is holding a read lock that
1601** it is trying to promote to a reserved lock and
1602** a second process is holding a reserved lock that it is trying
1603** to promote to an exclusive lock. The first process cannot proceed
1604** because it is blocked by the second and the second process cannot
1605** proceed because it is blocked by the first. If both processes
drhf5befa02007-12-06 02:42:07 +00001606** invoke the busy handlers, neither will make any progress. Therefore,
drh6ed48bf2007-06-14 20:57:18 +00001607** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
drh86939b52007-01-10 12:54:51 +00001608** will induce the first process to release its read lock and allow
1609** the second process to proceed.
1610**
drhd68eee02009-12-11 03:44:18 +00001611** ^The default busy callback is NULL.
drh2dfbbca2000-07-28 14:32:48 +00001612**
drhd68eee02009-12-11 03:44:18 +00001613** ^The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
drhfddfa2d2007-12-05 18:05:16 +00001614** when SQLite is in the middle of a large transaction where all the
drh33c1be32008-01-30 16:16:14 +00001615** changes will not fit into the in-memory cache. SQLite will
drh6ed48bf2007-06-14 20:57:18 +00001616** already hold a RESERVED lock on the database file, but it needs
1617** to promote this lock to EXCLUSIVE so that it can spill cache
1618** pages into the database file without harm to concurrent
drhd68eee02009-12-11 03:44:18 +00001619** readers. ^If it is unable to promote the lock, then the in-memory
drh6ed48bf2007-06-14 20:57:18 +00001620** cache will be left in an inconsistent state and so the error
1621** code is promoted from the relatively benign [SQLITE_BUSY] to
drhd68eee02009-12-11 03:44:18 +00001622** the more severe [SQLITE_IOERR_BLOCKED]. ^This error code promotion
drh33c1be32008-01-30 16:16:14 +00001623** forces an automatic rollback of the changes. See the
mihailimdb4f2ad2008-06-21 11:20:48 +00001624** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
drh6ed48bf2007-06-14 20:57:18 +00001625** CorruptionFollowingBusyError</a> wiki page for a discussion of why
1626** this is important.
mihailimdb4f2ad2008-06-21 11:20:48 +00001627**
drhd68eee02009-12-11 03:44:18 +00001628** ^(There can only be a single busy handler defined for each
mihailimdb4f2ad2008-06-21 11:20:48 +00001629** [database connection]. Setting a new busy handler clears any
drhd68eee02009-12-11 03:44:18 +00001630** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
mihailimdb4f2ad2008-06-21 11:20:48 +00001631** will also set or clear the busy handler.
drhd677b3d2007-08-20 22:48:41 +00001632**
drhc8075422008-09-10 13:09:23 +00001633** The busy callback should not take any actions which modify the
1634** database connection that invoked the busy handler. Any such actions
1635** result in undefined behavior.
1636**
drh8b39db12009-02-18 18:37:58 +00001637** A busy handler must not close the database connection
1638** or [prepared statement] that invoked the busy handler.
drh2dfbbca2000-07-28 14:32:48 +00001639*/
danielk1977f9d64d22004-06-19 08:18:07 +00001640int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
drh2dfbbca2000-07-28 14:32:48 +00001641
1642/*
drhd68eee02009-12-11 03:44:18 +00001643** CAPI3REF: Set A Busy Timeout
drh6ed48bf2007-06-14 20:57:18 +00001644**
drhd68eee02009-12-11 03:44:18 +00001645** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
1646** for a specified amount of time when a table is locked. ^The handler
mihailimdb4f2ad2008-06-21 11:20:48 +00001647** will sleep multiple times until at least "ms" milliseconds of sleeping
drhd68eee02009-12-11 03:44:18 +00001648** have accumulated. ^After at least "ms" milliseconds of sleeping,
mihailimdb4f2ad2008-06-21 11:20:48 +00001649** the handler returns 0 which causes [sqlite3_step()] to return
1650** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
drh2dfbbca2000-07-28 14:32:48 +00001651**
drhd68eee02009-12-11 03:44:18 +00001652** ^Calling this routine with an argument less than or equal to zero
drh2dfbbca2000-07-28 14:32:48 +00001653** turns off all busy handlers.
drh6ed48bf2007-06-14 20:57:18 +00001654**
drhd68eee02009-12-11 03:44:18 +00001655** ^(There can only be a single busy handler for a particular
mihailimdb4f2ad2008-06-21 11:20:48 +00001656** [database connection] any any given moment. If another busy handler
1657** was defined (using [sqlite3_busy_handler()]) prior to calling
drhd68eee02009-12-11 03:44:18 +00001658** this routine, that other busy handler is cleared.)^
drh2dfbbca2000-07-28 14:32:48 +00001659*/
danielk1977f9d64d22004-06-19 08:18:07 +00001660int sqlite3_busy_timeout(sqlite3*, int ms);
drh2dfbbca2000-07-28 14:32:48 +00001661
drhe3710332000-09-29 13:30:53 +00001662/*
drhd68eee02009-12-11 03:44:18 +00001663** CAPI3REF: Convenience Routines For Running Queries
drh6ed48bf2007-06-14 20:57:18 +00001664**
drh33c1be32008-01-30 16:16:14 +00001665** Definition: A <b>result table</b> is memory data structure created by the
1666** [sqlite3_get_table()] interface. A result table records the
1667** complete query results from one or more queries.
drha18c5682000-10-08 22:20:57 +00001668**
drh33c1be32008-01-30 16:16:14 +00001669** The table conceptually has a number of rows and columns. But
1670** these numbers are not part of the result table itself. These
1671** numbers are obtained separately. Let N be the number of rows
1672** and M be the number of columns.
1673**
mihailimdb4f2ad2008-06-21 11:20:48 +00001674** A result table is an array of pointers to zero-terminated UTF-8 strings.
1675** There are (N+1)*M elements in the array. The first M pointers point
1676** to zero-terminated strings that contain the names of the columns.
1677** The remaining entries all point to query results. NULL values result
1678** in NULL pointers. All other values are in their UTF-8 zero-terminated
1679** string representation as returned by [sqlite3_column_text()].
drh33c1be32008-01-30 16:16:14 +00001680**
mihailimdb4f2ad2008-06-21 11:20:48 +00001681** A result table might consist of one or more memory allocations.
drh33c1be32008-01-30 16:16:14 +00001682** It is not safe to pass a result table directly to [sqlite3_free()].
1683** A result table should be deallocated using [sqlite3_free_table()].
1684**
1685** As an example of the result table format, suppose a query result
1686** is as follows:
drha18c5682000-10-08 22:20:57 +00001687**
drh8bacf972007-08-25 16:21:29 +00001688** <blockquote><pre>
drha18c5682000-10-08 22:20:57 +00001689** Name | Age
1690** -----------------------
1691** Alice | 43
1692** Bob | 28
1693** Cindy | 21
drh8bacf972007-08-25 16:21:29 +00001694** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001695**
drh33c1be32008-01-30 16:16:14 +00001696** There are two column (M==2) and three rows (N==3). Thus the
1697** result table has 8 entries. Suppose the result table is stored
1698** in an array names azResult. Then azResult holds this content:
drha18c5682000-10-08 22:20:57 +00001699**
drh8bacf972007-08-25 16:21:29 +00001700** <blockquote><pre>
1701** azResult&#91;0] = "Name";
1702** azResult&#91;1] = "Age";
1703** azResult&#91;2] = "Alice";
1704** azResult&#91;3] = "43";
1705** azResult&#91;4] = "Bob";
1706** azResult&#91;5] = "28";
1707** azResult&#91;6] = "Cindy";
1708** azResult&#91;7] = "21";
1709** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001710**
drhd68eee02009-12-11 03:44:18 +00001711** ^The sqlite3_get_table() function evaluates one or more
drh33c1be32008-01-30 16:16:14 +00001712** semicolon-separated SQL statements in the zero-terminated UTF-8
drhd68eee02009-12-11 03:44:18 +00001713** string of its 2nd parameter and returns a result table to the
drh33c1be32008-01-30 16:16:14 +00001714** pointer given in its 3rd parameter.
drha18c5682000-10-08 22:20:57 +00001715**
drhd68eee02009-12-11 03:44:18 +00001716** After the application has finished with the result from sqlite3_get_table(),
1717** it should pass the result table pointer to sqlite3_free_table() in order to
mihailimdb4f2ad2008-06-21 11:20:48 +00001718** release the memory that was malloced. Because of the way the
drh33c1be32008-01-30 16:16:14 +00001719** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
mihailimdb4f2ad2008-06-21 11:20:48 +00001720** function must not try to call [sqlite3_free()] directly. Only
drh33c1be32008-01-30 16:16:14 +00001721** [sqlite3_free_table()] is able to release the memory properly and safely.
drhe3710332000-09-29 13:30:53 +00001722**
drhd68eee02009-12-11 03:44:18 +00001723** ^(The sqlite3_get_table() interface is implemented as a wrapper around
drh33c1be32008-01-30 16:16:14 +00001724** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
1725** to any internal data structures of SQLite. It uses only the public
1726** interface defined here. As a consequence, errors that occur in the
1727** wrapper layer outside of the internal [sqlite3_exec()] call are not
drhd68eee02009-12-11 03:44:18 +00001728** reflected in subsequent calls to [sqlite3_errcode()] or
1729** [sqlite3_errmsg()].)^
drhe3710332000-09-29 13:30:53 +00001730*/
danielk19776f8a5032004-05-10 10:34:51 +00001731int sqlite3_get_table(
drhcf538f42008-06-27 14:51:52 +00001732 sqlite3 *db, /* An open database */
1733 const char *zSql, /* SQL to be evaluated */
1734 char ***pazResult, /* Results of the query */
1735 int *pnRow, /* Number of result rows written here */
1736 int *pnColumn, /* Number of result columns written here */
1737 char **pzErrmsg /* Error msg written here */
drhe3710332000-09-29 13:30:53 +00001738);
danielk19776f8a5032004-05-10 10:34:51 +00001739void sqlite3_free_table(char **result);
drhe3710332000-09-29 13:30:53 +00001740
drha18c5682000-10-08 22:20:57 +00001741/*
drhd68eee02009-12-11 03:44:18 +00001742** CAPI3REF: Formatted String Printing Functions
drh6ed48bf2007-06-14 20:57:18 +00001743**
shane7c7c3112009-08-17 15:31:23 +00001744** These routines are work-alikes of the "printf()" family of functions
drh6ed48bf2007-06-14 20:57:18 +00001745** from the standard C library.
1746**
drhd68eee02009-12-11 03:44:18 +00001747** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
drh6d2069d2007-08-14 01:58:53 +00001748** results into memory obtained from [sqlite3_malloc()].
drh33c1be32008-01-30 16:16:14 +00001749** The strings returned by these two routines should be
drhd68eee02009-12-11 03:44:18 +00001750** released by [sqlite3_free()]. ^Both routines return a
drh6ed48bf2007-06-14 20:57:18 +00001751** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
1752** memory to hold the resulting string.
1753**
drhd68eee02009-12-11 03:44:18 +00001754** ^(In sqlite3_snprintf() routine is similar to "snprintf()" from
drh6ed48bf2007-06-14 20:57:18 +00001755** the standard C library. The result is written into the
1756** buffer supplied as the second parameter whose size is given by
drh33c1be32008-01-30 16:16:14 +00001757** the first parameter. Note that the order of the
drhd68eee02009-12-11 03:44:18 +00001758** first two parameters is reversed from snprintf().)^ This is an
drh6ed48bf2007-06-14 20:57:18 +00001759** historical accident that cannot be fixed without breaking
drhd68eee02009-12-11 03:44:18 +00001760** backwards compatibility. ^(Note also that sqlite3_snprintf()
drh6ed48bf2007-06-14 20:57:18 +00001761** returns a pointer to its buffer instead of the number of
drhd68eee02009-12-11 03:44:18 +00001762** characters actually written into the buffer.)^ We admit that
drh6ed48bf2007-06-14 20:57:18 +00001763** the number of characters written would be a more useful return
1764** value but we cannot change the implementation of sqlite3_snprintf()
1765** now without breaking compatibility.
1766**
drhd68eee02009-12-11 03:44:18 +00001767** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
1768** guarantees that the buffer is always zero-terminated. ^The first
drh6ed48bf2007-06-14 20:57:18 +00001769** parameter "n" is the total size of the buffer, including space for
drh33c1be32008-01-30 16:16:14 +00001770** the zero terminator. So the longest string that can be completely
drh6ed48bf2007-06-14 20:57:18 +00001771** written will be n-1 characters.
1772**
1773** These routines all implement some additional formatting
drh4f26d6c2004-05-26 23:25:30 +00001774** options that are useful for constructing SQL statements.
shane26b34032008-05-23 17:21:09 +00001775** All of the usual printf() formatting options apply. In addition, there
drh153c62c2007-08-24 03:51:33 +00001776** is are "%q", "%Q", and "%z" options.
drh6ed48bf2007-06-14 20:57:18 +00001777**
drhd68eee02009-12-11 03:44:18 +00001778** ^(The %q option works like %s in that it substitutes a null-terminated
drh66b89c82000-11-28 20:47:17 +00001779** string from the argument list. But %q also doubles every '\'' character.
drhd68eee02009-12-11 03:44:18 +00001780** %q is designed for use inside a string literal.)^ By doubling each '\''
drh66b89c82000-11-28 20:47:17 +00001781** character it escapes that character and allows it to be inserted into
drha18c5682000-10-08 22:20:57 +00001782** the string.
1783**
mihailimdb4f2ad2008-06-21 11:20:48 +00001784** For example, assume the string variable zText contains text as follows:
drha18c5682000-10-08 22:20:57 +00001785**
drh6ed48bf2007-06-14 20:57:18 +00001786** <blockquote><pre>
1787** char *zText = "It's a happy day!";
1788** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001789**
drh6ed48bf2007-06-14 20:57:18 +00001790** One can use this text in an SQL statement as follows:
drha18c5682000-10-08 22:20:57 +00001791**
drh6ed48bf2007-06-14 20:57:18 +00001792** <blockquote><pre>
1793** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
1794** sqlite3_exec(db, zSQL, 0, 0, 0);
1795** sqlite3_free(zSQL);
1796** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001797**
1798** Because the %q format string is used, the '\'' character in zText
1799** is escaped and the SQL generated is as follows:
1800**
drh6ed48bf2007-06-14 20:57:18 +00001801** <blockquote><pre>
1802** INSERT INTO table1 VALUES('It''s a happy day!')
1803** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001804**
1805** This is correct. Had we used %s instead of %q, the generated SQL
1806** would have looked like this:
1807**
drh6ed48bf2007-06-14 20:57:18 +00001808** <blockquote><pre>
1809** INSERT INTO table1 VALUES('It's a happy day!');
1810** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001811**
mihailimdb4f2ad2008-06-21 11:20:48 +00001812** This second example is an SQL syntax error. As a general rule you should
1813** always use %q instead of %s when inserting text into a string literal.
drh6ed48bf2007-06-14 20:57:18 +00001814**
drhd68eee02009-12-11 03:44:18 +00001815** ^(The %Q option works like %q except it also adds single quotes around
mihailimdb4f2ad2008-06-21 11:20:48 +00001816** the outside of the total string. Additionally, if the parameter in the
1817** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
drhd68eee02009-12-11 03:44:18 +00001818** single quotes).)^ So, for example, one could say:
drh6ed48bf2007-06-14 20:57:18 +00001819**
1820** <blockquote><pre>
1821** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
1822** sqlite3_exec(db, zSQL, 0, 0, 0);
1823** sqlite3_free(zSQL);
1824** </pre></blockquote>
1825**
1826** The code above will render a correct SQL statement in the zSQL
1827** variable even if the zText variable is a NULL pointer.
drh153c62c2007-08-24 03:51:33 +00001828**
drhd68eee02009-12-11 03:44:18 +00001829** ^(The "%z" formatting option works like "%s" but with the
drh153c62c2007-08-24 03:51:33 +00001830** addition that after the string has been read and copied into
drhd68eee02009-12-11 03:44:18 +00001831** the result, [sqlite3_free()] is called on the input string.)^
drha18c5682000-10-08 22:20:57 +00001832*/
danielk19776f8a5032004-05-10 10:34:51 +00001833char *sqlite3_mprintf(const char*,...);
1834char *sqlite3_vmprintf(const char*, va_list);
drhfeac5f82004-08-01 00:10:45 +00001835char *sqlite3_snprintf(int,char*,const char*, ...);
drh5191b7e2002-03-08 02:12:00 +00001836
drh28dd4792006-06-26 21:35:44 +00001837/*
drhd68eee02009-12-11 03:44:18 +00001838** CAPI3REF: Memory Allocation Subsystem
drhd84f9462007-08-15 11:28:56 +00001839**
drhd68eee02009-12-11 03:44:18 +00001840** The SQLite core uses these three routines for all of its own
drh33c1be32008-01-30 16:16:14 +00001841** internal memory allocation needs. "Core" in the previous sentence
drhf5befa02007-12-06 02:42:07 +00001842** does not include operating-system specific VFS implementation. The
shane26b34032008-05-23 17:21:09 +00001843** Windows VFS uses native malloc() and free() for some operations.
drhd64621d2007-11-05 17:54:17 +00001844**
drhd68eee02009-12-11 03:44:18 +00001845** ^The sqlite3_malloc() routine returns a pointer to a block
drhfddfa2d2007-12-05 18:05:16 +00001846** of memory at least N bytes in length, where N is the parameter.
drhd68eee02009-12-11 03:44:18 +00001847** ^If sqlite3_malloc() is unable to obtain sufficient free
1848** memory, it returns a NULL pointer. ^If the parameter N to
drhfddfa2d2007-12-05 18:05:16 +00001849** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
1850** a NULL pointer.
1851**
drhd68eee02009-12-11 03:44:18 +00001852** ^Calling sqlite3_free() with a pointer previously returned
drhfddfa2d2007-12-05 18:05:16 +00001853** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
drhd68eee02009-12-11 03:44:18 +00001854** that it might be reused. ^The sqlite3_free() routine is
drhfddfa2d2007-12-05 18:05:16 +00001855** a no-op if is called with a NULL pointer. Passing a NULL pointer
drh33c1be32008-01-30 16:16:14 +00001856** to sqlite3_free() is harmless. After being freed, memory
drhfddfa2d2007-12-05 18:05:16 +00001857** should neither be read nor written. Even reading previously freed
1858** memory might result in a segmentation fault or other severe error.
drh33c1be32008-01-30 16:16:14 +00001859** Memory corruption, a segmentation fault, or other severe error
drhfddfa2d2007-12-05 18:05:16 +00001860** might result if sqlite3_free() is called with a non-NULL pointer that
drh7b228b32008-10-17 15:10:37 +00001861** was not obtained from sqlite3_malloc() or sqlite3_realloc().
drhfddfa2d2007-12-05 18:05:16 +00001862**
drhd68eee02009-12-11 03:44:18 +00001863** ^(The sqlite3_realloc() interface attempts to resize a
drhfddfa2d2007-12-05 18:05:16 +00001864** prior memory allocation to be at least N bytes, where N is the
1865** second parameter. The memory allocation to be resized is the first
drhd68eee02009-12-11 03:44:18 +00001866** parameter.)^ ^ If the first parameter to sqlite3_realloc()
drhfddfa2d2007-12-05 18:05:16 +00001867** is a NULL pointer then its behavior is identical to calling
1868** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
drhd68eee02009-12-11 03:44:18 +00001869** ^If the second parameter to sqlite3_realloc() is zero or
drhfddfa2d2007-12-05 18:05:16 +00001870** negative then the behavior is exactly the same as calling
1871** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
drhd68eee02009-12-11 03:44:18 +00001872** ^sqlite3_realloc() returns a pointer to a memory allocation
drhfddfa2d2007-12-05 18:05:16 +00001873** of at least N bytes in size or NULL if sufficient memory is unavailable.
drhd68eee02009-12-11 03:44:18 +00001874** ^If M is the size of the prior allocation, then min(N,M) bytes
drhfddfa2d2007-12-05 18:05:16 +00001875** of the prior allocation are copied into the beginning of buffer returned
1876** by sqlite3_realloc() and the prior allocation is freed.
drhd68eee02009-12-11 03:44:18 +00001877** ^If sqlite3_realloc() returns NULL, then the prior allocation
drhfddfa2d2007-12-05 18:05:16 +00001878** is not freed.
1879**
drhd68eee02009-12-11 03:44:18 +00001880** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
1881** is always aligned to at least an 8 byte boundary.
drhd64621d2007-11-05 17:54:17 +00001882**
1883** In SQLite version 3.5.0 and 3.5.1, it was possible to define
1884** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
1885** implementation of these routines to be omitted. That capability
mihailimdb4f2ad2008-06-21 11:20:48 +00001886** is no longer provided. Only built-in memory allocators can be used.
drh8bacf972007-08-25 16:21:29 +00001887**
shane26b34032008-05-23 17:21:09 +00001888** The Windows OS interface layer calls
drh8bacf972007-08-25 16:21:29 +00001889** the system malloc() and free() directly when converting
1890** filenames between the UTF-8 encoding used by SQLite
shane26b34032008-05-23 17:21:09 +00001891** and whatever filename encoding is used by the particular Windows
drh8bacf972007-08-25 16:21:29 +00001892** installation. Memory allocation errors are detected, but
1893** they are reported back as [SQLITE_CANTOPEN] or
1894** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
drh33c1be32008-01-30 16:16:14 +00001895**
drh8b39db12009-02-18 18:37:58 +00001896** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
1897** must be either NULL or else pointers obtained from a prior
1898** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
1899** not yet been released.
drh33c1be32008-01-30 16:16:14 +00001900**
drh8b39db12009-02-18 18:37:58 +00001901** The application must not read or write any part of
1902** a block of memory after it has been released using
1903** [sqlite3_free()] or [sqlite3_realloc()].
drh28dd4792006-06-26 21:35:44 +00001904*/
drhf3a65f72007-08-22 20:18:21 +00001905void *sqlite3_malloc(int);
1906void *sqlite3_realloc(void*, int);
drh28dd4792006-06-26 21:35:44 +00001907void sqlite3_free(void*);
1908
drh5191b7e2002-03-08 02:12:00 +00001909/*
drhd68eee02009-12-11 03:44:18 +00001910** CAPI3REF: Memory Allocator Statistics
drhd84f9462007-08-15 11:28:56 +00001911**
drh33c1be32008-01-30 16:16:14 +00001912** SQLite provides these two interfaces for reporting on the status
1913** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
mihailimdb4f2ad2008-06-21 11:20:48 +00001914** routines, which form the built-in memory allocation subsystem.
drhd84f9462007-08-15 11:28:56 +00001915**
drhd68eee02009-12-11 03:44:18 +00001916** ^The [sqlite3_memory_used()] routine returns the number of bytes
1917** of memory currently outstanding (malloced but not freed).
1918** ^The [sqlite3_memory_highwater()] routine returns the maximum
1919** value of [sqlite3_memory_used()] since the high-water mark
1920** was last reset. ^The values returned by [sqlite3_memory_used()] and
1921** [sqlite3_memory_highwater()] include any overhead
1922** added by SQLite in its implementation of [sqlite3_malloc()],
1923** but not overhead added by the any underlying system library
1924** routines that [sqlite3_malloc()] may call.
1925**
1926** ^The memory high-water mark is reset to the current value of
1927** [sqlite3_memory_used()] if and only if the parameter to
1928** [sqlite3_memory_highwater()] is true. ^The value returned
1929** by [sqlite3_memory_highwater(1)] is the high-water mark
1930** prior to the reset.
drhd84f9462007-08-15 11:28:56 +00001931*/
drh153c62c2007-08-24 03:51:33 +00001932sqlite3_int64 sqlite3_memory_used(void);
1933sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
drhd84f9462007-08-15 11:28:56 +00001934
1935/*
drhd68eee02009-12-11 03:44:18 +00001936** CAPI3REF: Pseudo-Random Number Generator
drh2fa18682008-03-19 14:15:34 +00001937**
1938** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
drh49c3d572008-12-15 22:51:38 +00001939** select random [ROWID | ROWIDs] when inserting new records into a table that
1940** already uses the largest possible [ROWID]. The PRNG is also used for
drh2fa18682008-03-19 14:15:34 +00001941** the build-in random() and randomblob() SQL functions. This interface allows
shane26b34032008-05-23 17:21:09 +00001942** applications to access the same PRNG for other purposes.
drh2fa18682008-03-19 14:15:34 +00001943**
drhd68eee02009-12-11 03:44:18 +00001944** ^A call to this routine stores N bytes of randomness into buffer P.
drh2fa18682008-03-19 14:15:34 +00001945**
drhd68eee02009-12-11 03:44:18 +00001946** ^The first time this routine is invoked (either internally or by
drh2fa18682008-03-19 14:15:34 +00001947** the application) the PRNG is seeded using randomness obtained
1948** from the xRandomness method of the default [sqlite3_vfs] object.
drhd68eee02009-12-11 03:44:18 +00001949** ^On all subsequent invocations, the pseudo-randomness is generated
drh2fa18682008-03-19 14:15:34 +00001950** internally and without recourse to the [sqlite3_vfs] xRandomness
1951** method.
drh2fa18682008-03-19 14:15:34 +00001952*/
1953void sqlite3_randomness(int N, void *P);
1954
1955/*
drhd68eee02009-12-11 03:44:18 +00001956** CAPI3REF: Compile-Time Authorization Callbacks
drhfddfa2d2007-12-05 18:05:16 +00001957**
drhd68eee02009-12-11 03:44:18 +00001958** ^This routine registers a authorizer callback with a particular
drhf47ce562008-03-20 18:00:49 +00001959** [database connection], supplied in the first argument.
drhd68eee02009-12-11 03:44:18 +00001960** ^The authorizer callback is invoked as SQL statements are being compiled
drh6ed48bf2007-06-14 20:57:18 +00001961** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
drhd68eee02009-12-11 03:44:18 +00001962** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various
drh6ed48bf2007-06-14 20:57:18 +00001963** points during the compilation process, as logic is being created
1964** to perform various actions, the authorizer callback is invoked to
drhd68eee02009-12-11 03:44:18 +00001965** see if those actions are allowed. ^The authorizer callback should
drhf47ce562008-03-20 18:00:49 +00001966** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
drh6ed48bf2007-06-14 20:57:18 +00001967** specific action but allow the SQL statement to continue to be
1968** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
drhd68eee02009-12-11 03:44:18 +00001969** rejected with an error. ^If the authorizer callback returns
drhf5befa02007-12-06 02:42:07 +00001970** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
mihailima3f64902008-06-21 13:35:56 +00001971** then the [sqlite3_prepare_v2()] or equivalent call that triggered
drh33c1be32008-01-30 16:16:14 +00001972** the authorizer will fail with an error message.
drh6ed48bf2007-06-14 20:57:18 +00001973**
drhf5befa02007-12-06 02:42:07 +00001974** When the callback returns [SQLITE_OK], that means the operation
drhd68eee02009-12-11 03:44:18 +00001975** requested is ok. ^When the callback returns [SQLITE_DENY], the
drhf5befa02007-12-06 02:42:07 +00001976** [sqlite3_prepare_v2()] or equivalent call that triggered the
drh33c1be32008-01-30 16:16:14 +00001977** authorizer will fail with an error message explaining that
drh959b5302009-04-30 15:59:56 +00001978** access is denied.
drh6ed48bf2007-06-14 20:57:18 +00001979**
drhd68eee02009-12-11 03:44:18 +00001980** ^The first parameter to the authorizer callback is a copy of the third
1981** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
mihailima3f64902008-06-21 13:35:56 +00001982** to the callback is an integer [SQLITE_COPY | action code] that specifies
drhd68eee02009-12-11 03:44:18 +00001983** the particular action to be authorized. ^The third through sixth parameters
mihailima3f64902008-06-21 13:35:56 +00001984** to the callback are zero-terminated strings that contain additional
1985** details about the action to be authorized.
drh6ed48bf2007-06-14 20:57:18 +00001986**
drhd68eee02009-12-11 03:44:18 +00001987** ^If the action code is [SQLITE_READ]
drh959b5302009-04-30 15:59:56 +00001988** and the callback returns [SQLITE_IGNORE] then the
1989** [prepared statement] statement is constructed to substitute
1990** a NULL value in place of the table column that would have
1991** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
1992** return can be used to deny an untrusted user access to individual
1993** columns of a table.
drhd68eee02009-12-11 03:44:18 +00001994** ^If the action code is [SQLITE_DELETE] and the callback returns
drh959b5302009-04-30 15:59:56 +00001995** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
1996** [truncate optimization] is disabled and all rows are deleted individually.
1997**
drhf47ce562008-03-20 18:00:49 +00001998** An authorizer is used when [sqlite3_prepare | preparing]
mihailimebe796c2008-06-21 20:11:17 +00001999** SQL statements from an untrusted source, to ensure that the SQL statements
2000** do not try to access data they are not allowed to see, or that they do not
2001** try to execute malicious statements that damage the database. For
drh6ed48bf2007-06-14 20:57:18 +00002002** example, an application may allow a user to enter arbitrary
2003** SQL queries for evaluation by a database. But the application does
2004** not want the user to be able to make arbitrary changes to the
2005** database. An authorizer could then be put in place while the
drhf47ce562008-03-20 18:00:49 +00002006** user-entered SQL is being [sqlite3_prepare | prepared] that
2007** disallows everything except [SELECT] statements.
2008**
2009** Applications that need to process SQL from untrusted sources
2010** might also consider lowering resource limits using [sqlite3_limit()]
2011** and limiting database size using the [max_page_count] [PRAGMA]
2012** in addition to using an authorizer.
drh6ed48bf2007-06-14 20:57:18 +00002013**
drhd68eee02009-12-11 03:44:18 +00002014** ^(Only a single authorizer can be in place on a database connection
drh6ed48bf2007-06-14 20:57:18 +00002015** at a time. Each call to sqlite3_set_authorizer overrides the
drhd68eee02009-12-11 03:44:18 +00002016** previous call.)^ ^Disable the authorizer by installing a NULL callback.
drh33c1be32008-01-30 16:16:14 +00002017** The authorizer is disabled by default.
drh6ed48bf2007-06-14 20:57:18 +00002018**
drhc8075422008-09-10 13:09:23 +00002019** The authorizer callback must not do anything that will modify
2020** the database connection that invoked the authorizer callback.
2021** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2022** database connections for the meaning of "modify" in this paragraph.
2023**
drhd68eee02009-12-11 03:44:18 +00002024** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
shane7c7c3112009-08-17 15:31:23 +00002025** statement might be re-prepared during [sqlite3_step()] due to a
drh7b37c5d2008-08-12 14:51:29 +00002026** schema change. Hence, the application should ensure that the
2027** correct authorizer callback remains in place during the [sqlite3_step()].
2028**
drhd68eee02009-12-11 03:44:18 +00002029** ^Note that the authorizer callback is invoked only during
drh33c1be32008-01-30 16:16:14 +00002030** [sqlite3_prepare()] or its variants. Authorization is not
drh959b5302009-04-30 15:59:56 +00002031** performed during statement evaluation in [sqlite3_step()], unless
2032** as stated in the previous paragraph, sqlite3_step() invokes
2033** sqlite3_prepare_v2() to reprepare a statement after a schema change.
drhed6c8672003-01-12 18:02:16 +00002034*/
danielk19776f8a5032004-05-10 10:34:51 +00002035int sqlite3_set_authorizer(
danielk1977f9d64d22004-06-19 08:18:07 +00002036 sqlite3*,
drhe22a3342003-04-22 20:30:37 +00002037 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
drhe5f9c642003-01-13 23:27:31 +00002038 void *pUserData
drhed6c8672003-01-12 18:02:16 +00002039);
2040
2041/*
drhd68eee02009-12-11 03:44:18 +00002042** CAPI3REF: Authorizer Return Codes
drh6ed48bf2007-06-14 20:57:18 +00002043**
2044** The [sqlite3_set_authorizer | authorizer callback function] must
2045** return either [SQLITE_OK] or one of these two constants in order
2046** to signal SQLite whether or not the action is permitted. See the
2047** [sqlite3_set_authorizer | authorizer documentation] for additional
2048** information.
2049*/
2050#define SQLITE_DENY 1 /* Abort the SQL statement with an error */
2051#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
2052
2053/*
drhd68eee02009-12-11 03:44:18 +00002054** CAPI3REF: Authorizer Action Codes
drh6ed48bf2007-06-14 20:57:18 +00002055**
2056** The [sqlite3_set_authorizer()] interface registers a callback function
mihailima3f64902008-06-21 13:35:56 +00002057** that is invoked to authorize certain SQL statement actions. The
drh6ed48bf2007-06-14 20:57:18 +00002058** second parameter to the callback is an integer code that specifies
2059** what action is being authorized. These are the integer action codes that
drh33c1be32008-01-30 16:16:14 +00002060** the authorizer callback may be passed.
drh6ed48bf2007-06-14 20:57:18 +00002061**
mihailima3f64902008-06-21 13:35:56 +00002062** These action code values signify what kind of operation is to be
drh33c1be32008-01-30 16:16:14 +00002063** authorized. The 3rd and 4th parameters to the authorization
drhf5befa02007-12-06 02:42:07 +00002064** callback function will be parameters or NULL depending on which of these
drh7a98b852009-12-13 23:03:01 +00002065** codes is used as the second parameter. ^(The 5th parameter to the
mihailima3f64902008-06-21 13:35:56 +00002066** authorizer callback is the name of the database ("main", "temp",
drh7a98b852009-12-13 23:03:01 +00002067** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
drh5cf590c2003-04-24 01:45:04 +00002068** is the name of the inner-most trigger or view that is responsible for
mihailima3f64902008-06-21 13:35:56 +00002069** the access attempt or NULL if this access attempt is directly from
drh6ed48bf2007-06-14 20:57:18 +00002070** top-level SQL code.
drhed6c8672003-01-12 18:02:16 +00002071*/
drh6ed48bf2007-06-14 20:57:18 +00002072/******************************************* 3rd ************ 4th ***********/
drhe5f9c642003-01-13 23:27:31 +00002073#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
2074#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
2075#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
2076#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002077#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002078#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002079#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002080#define SQLITE_CREATE_VIEW 8 /* View Name NULL */
2081#define SQLITE_DELETE 9 /* Table Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002082#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002083#define SQLITE_DROP_TABLE 11 /* Table Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002084#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002085#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002086#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002087#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002088#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002089#define SQLITE_DROP_VIEW 17 /* View Name NULL */
2090#define SQLITE_INSERT 18 /* Table Name NULL */
2091#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
2092#define SQLITE_READ 20 /* Table Name Column Name */
2093#define SQLITE_SELECT 21 /* NULL NULL */
danielk1977ab9b7032008-12-30 06:24:58 +00002094#define SQLITE_TRANSACTION 22 /* Operation NULL */
drhe5f9c642003-01-13 23:27:31 +00002095#define SQLITE_UPDATE 23 /* Table Name Column Name */
drh81e293b2003-06-06 19:00:42 +00002096#define SQLITE_ATTACH 24 /* Filename NULL */
2097#define SQLITE_DETACH 25 /* Database Name NULL */
danielk19771c8c23c2004-11-12 15:53:37 +00002098#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
danielk19771d54df82004-11-23 15:41:16 +00002099#define SQLITE_REINDEX 27 /* Index Name NULL */
drhe6e04962005-07-23 02:17:03 +00002100#define SQLITE_ANALYZE 28 /* Table Name NULL */
danielk1977f1a381e2006-06-16 08:01:02 +00002101#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
2102#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
drh2e904c52008-11-10 23:54:05 +00002103#define SQLITE_FUNCTION 31 /* NULL Function Name */
danielk1977ab9b7032008-12-30 06:24:58 +00002104#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
drh6ed48bf2007-06-14 20:57:18 +00002105#define SQLITE_COPY 0 /* No longer used */
drhed6c8672003-01-12 18:02:16 +00002106
2107/*
drhd68eee02009-12-11 03:44:18 +00002108** CAPI3REF: Tracing And Profiling Functions
drh6ed48bf2007-06-14 20:57:18 +00002109**
2110** These routines register callback functions that can be used for
2111** tracing and profiling the execution of SQL statements.
drhfddfa2d2007-12-05 18:05:16 +00002112**
drhd68eee02009-12-11 03:44:18 +00002113** ^The callback function registered by sqlite3_trace() is invoked at
drh33c1be32008-01-30 16:16:14 +00002114** various times when an SQL statement is being run by [sqlite3_step()].
drhd68eee02009-12-11 03:44:18 +00002115** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
2116** SQL statement text as the statement first begins executing.
2117** ^(Additional sqlite3_trace() callbacks might occur
shane26b34032008-05-23 17:21:09 +00002118** as each triggered subprogram is entered. The callbacks for triggers
drhd68eee02009-12-11 03:44:18 +00002119** contain a UTF-8 SQL comment that identifies the trigger.)^
mihailima3f64902008-06-21 13:35:56 +00002120**
drhd68eee02009-12-11 03:44:18 +00002121** ^The callback function registered by sqlite3_profile() is invoked
2122** as each SQL statement finishes. ^The profile callback contains
drh33c1be32008-01-30 16:16:14 +00002123** the original statement text and an estimate of wall-clock time
2124** of how long that statement took to run.
drh18de4822003-01-16 16:28:53 +00002125*/
drh9f8da322010-03-10 20:06:37 +00002126void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
shanea79c3cc2008-08-11 17:27:01 +00002127SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
drh6d2069d2007-08-14 01:58:53 +00002128 void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
drh18de4822003-01-16 16:28:53 +00002129
danielk1977348bb5d2003-10-18 09:37:26 +00002130/*
drhd68eee02009-12-11 03:44:18 +00002131** CAPI3REF: Query Progress Callbacks
drh6ed48bf2007-06-14 20:57:18 +00002132**
drhd68eee02009-12-11 03:44:18 +00002133** ^This routine configures a callback function - the
drhfddfa2d2007-12-05 18:05:16 +00002134** progress callback - that is invoked periodically during long
2135** running calls to [sqlite3_exec()], [sqlite3_step()] and
mihailima3f64902008-06-21 13:35:56 +00002136** [sqlite3_get_table()]. An example use for this
drh6ed48bf2007-06-14 20:57:18 +00002137** interface is to keep a GUI updated during a large query.
danielk1977348bb5d2003-10-18 09:37:26 +00002138**
drhd68eee02009-12-11 03:44:18 +00002139** ^If the progress callback returns non-zero, the operation is
drh33c1be32008-01-30 16:16:14 +00002140** interrupted. This feature can be used to implement a
drhc8075422008-09-10 13:09:23 +00002141** "Cancel" button on a GUI progress dialog box.
2142**
2143** The progress handler must not do anything that will modify
2144** the database connection that invoked the progress handler.
2145** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2146** database connections for the meaning of "modify" in this paragraph.
danielk1977348bb5d2003-10-18 09:37:26 +00002147**
danielk1977348bb5d2003-10-18 09:37:26 +00002148*/
danielk1977f9d64d22004-06-19 08:18:07 +00002149void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
danielk1977348bb5d2003-10-18 09:37:26 +00002150
drhaa940ea2004-01-15 02:44:03 +00002151/*
drhd68eee02009-12-11 03:44:18 +00002152** CAPI3REF: Opening A New Database Connection
drhaa940ea2004-01-15 02:44:03 +00002153**
drhd68eee02009-12-11 03:44:18 +00002154** ^These routines open an SQLite database file whose name is given by the
2155** filename argument. ^The filename argument is interpreted as UTF-8 for
mihailima3f64902008-06-21 13:35:56 +00002156** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
drhd68eee02009-12-11 03:44:18 +00002157** order for sqlite3_open16(). ^(A [database connection] handle is usually
mihailima3f64902008-06-21 13:35:56 +00002158** returned in *ppDb, even if an error occurs. The only exception is that
2159** if SQLite is unable to allocate memory to hold the [sqlite3] object,
2160** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
drhd68eee02009-12-11 03:44:18 +00002161** object.)^ ^(If the database is opened (and/or created) successfully, then
2162** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
mihailima3f64902008-06-21 13:35:56 +00002163** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
drhd68eee02009-12-11 03:44:18 +00002164** an English language description of the error following a failure of any
2165** of the sqlite3_open() routines.
drh22fbcb82004-02-01 01:22:50 +00002166**
drhd68eee02009-12-11 03:44:18 +00002167** ^The default encoding for the database will be UTF-8 if
mihailima3f64902008-06-21 13:35:56 +00002168** sqlite3_open() or sqlite3_open_v2() is called and
2169** UTF-16 in the native byte order if sqlite3_open16() is used.
danielk197765904932004-05-26 06:18:37 +00002170**
drh33c1be32008-01-30 16:16:14 +00002171** Whether or not an error occurs when it is opened, resources
mihailima3f64902008-06-21 13:35:56 +00002172** associated with the [database connection] handle should be released by
2173** passing it to [sqlite3_close()] when it is no longer required.
drh6d2069d2007-08-14 01:58:53 +00002174**
mihailima3f64902008-06-21 13:35:56 +00002175** The sqlite3_open_v2() interface works like sqlite3_open()
shane26b34032008-05-23 17:21:09 +00002176** except that it accepts two additional parameters for additional control
drhd68eee02009-12-11 03:44:18 +00002177** over the new database connection. ^(The flags parameter to
2178** sqlite3_open_v2() can take one of
danielk19779a6284c2008-07-10 17:52:49 +00002179** the following three values, optionally combined with the
drhf1f12682009-09-09 14:17:52 +00002180** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
drhd68eee02009-12-11 03:44:18 +00002181** and/or [SQLITE_OPEN_PRIVATECACHE] flags:)^
drh6d2069d2007-08-14 01:58:53 +00002182**
mihailima3f64902008-06-21 13:35:56 +00002183** <dl>
drhd68eee02009-12-11 03:44:18 +00002184** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
mihailima3f64902008-06-21 13:35:56 +00002185** <dd>The database is opened in read-only mode. If the database does not
drhd68eee02009-12-11 03:44:18 +00002186** already exist, an error is returned.</dd>)^
drh6d2069d2007-08-14 01:58:53 +00002187**
drhd68eee02009-12-11 03:44:18 +00002188** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
mihailima3f64902008-06-21 13:35:56 +00002189** <dd>The database is opened for reading and writing if possible, or reading
2190** only if the file is write protected by the operating system. In either
drhd68eee02009-12-11 03:44:18 +00002191** case the database must already exist, otherwise an error is returned.</dd>)^
drh9da9d962007-08-28 15:47:44 +00002192**
drhd68eee02009-12-11 03:44:18 +00002193** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
mihailima3f64902008-06-21 13:35:56 +00002194** <dd>The database is opened for reading and writing, and is creates it if
2195** it does not already exist. This is the behavior that is always used for
drhd68eee02009-12-11 03:44:18 +00002196** sqlite3_open() and sqlite3_open16().</dd>)^
mihailima3f64902008-06-21 13:35:56 +00002197** </dl>
2198**
2199** If the 3rd parameter to sqlite3_open_v2() is not one of the
danielk19779a6284c2008-07-10 17:52:49 +00002200** combinations shown above or one of the combinations shown above combined
drhf1f12682009-09-09 14:17:52 +00002201** with the [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX],
2202** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_SHAREDCACHE] flags,
drhafacce02008-09-02 21:35:03 +00002203** then the behavior is undefined.
danielk19779a6284c2008-07-10 17:52:49 +00002204**
drhd68eee02009-12-11 03:44:18 +00002205** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
drhafacce02008-09-02 21:35:03 +00002206** opens in the multi-thread [threading mode] as long as the single-thread
drhd68eee02009-12-11 03:44:18 +00002207** mode has not been set at compile-time or start-time. ^If the
drhafacce02008-09-02 21:35:03 +00002208** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
2209** in the serialized [threading mode] unless single-thread was
2210** previously selected at compile-time or start-time.
drhd68eee02009-12-11 03:44:18 +00002211** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
drhf1f12682009-09-09 14:17:52 +00002212** eligible to use [shared cache mode], regardless of whether or not shared
drhd68eee02009-12-11 03:44:18 +00002213** cache is enabled using [sqlite3_enable_shared_cache()]. ^The
drhf1f12682009-09-09 14:17:52 +00002214** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
2215** participate in [shared cache mode] even if it is enabled.
drhd9b97cf2008-04-10 13:38:17 +00002216**
drhd68eee02009-12-11 03:44:18 +00002217** ^If the filename is ":memory:", then a private, temporary in-memory database
2218** is created for the connection. ^This in-memory database will vanish when
mihailima3f64902008-06-21 13:35:56 +00002219** the database connection is closed. Future versions of SQLite might
2220** make use of additional special filenames that begin with the ":" character.
2221** It is recommended that when a database filename actually does begin with
2222** a ":" character you should prefix the filename with a pathname such as
2223** "./" to avoid ambiguity.
drh6d2069d2007-08-14 01:58:53 +00002224**
drhd68eee02009-12-11 03:44:18 +00002225** ^If the filename is an empty string, then a private, temporary
2226** on-disk database will be created. ^This private database will be
drh3f3b6352007-09-03 20:32:45 +00002227** automatically deleted as soon as the database connection is closed.
2228**
drhd68eee02009-12-11 03:44:18 +00002229** ^The fourth parameter to sqlite3_open_v2() is the name of the
mihailima3f64902008-06-21 13:35:56 +00002230** [sqlite3_vfs] object that defines the operating system interface that
drhd68eee02009-12-11 03:44:18 +00002231** the new database connection should use. ^If the fourth parameter is
mihailima3f64902008-06-21 13:35:56 +00002232** a NULL pointer then the default [sqlite3_vfs] object is used.
drh6ed48bf2007-06-14 20:57:18 +00002233**
shane26b34032008-05-23 17:21:09 +00002234** <b>Note to Windows users:</b> The encoding used for the filename argument
mihailima3f64902008-06-21 13:35:56 +00002235** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
drh9da9d962007-08-28 15:47:44 +00002236** codepage is currently defined. Filenames containing international
2237** characters must be converted to UTF-8 prior to passing them into
mihailima3f64902008-06-21 13:35:56 +00002238** sqlite3_open() or sqlite3_open_v2().
danielk197765904932004-05-26 06:18:37 +00002239*/
2240int sqlite3_open(
2241 const char *filename, /* Database filename (UTF-8) */
danielk19774f057f92004-06-08 00:02:33 +00002242 sqlite3 **ppDb /* OUT: SQLite db handle */
danielk197765904932004-05-26 06:18:37 +00002243);
danielk197765904932004-05-26 06:18:37 +00002244int sqlite3_open16(
2245 const void *filename, /* Database filename (UTF-16) */
danielk19774f057f92004-06-08 00:02:33 +00002246 sqlite3 **ppDb /* OUT: SQLite db handle */
danielk197765904932004-05-26 06:18:37 +00002247);
drh6d2069d2007-08-14 01:58:53 +00002248int sqlite3_open_v2(
drh428e2822007-08-30 16:23:19 +00002249 const char *filename, /* Database filename (UTF-8) */
drh6d2069d2007-08-14 01:58:53 +00002250 sqlite3 **ppDb, /* OUT: SQLite db handle */
2251 int flags, /* Flags */
drhd84f9462007-08-15 11:28:56 +00002252 const char *zVfs /* Name of VFS module to use */
drh6d2069d2007-08-14 01:58:53 +00002253);
danielk1977295ba552004-05-19 10:34:51 +00002254
danielk197765904932004-05-26 06:18:37 +00002255/*
drhd68eee02009-12-11 03:44:18 +00002256** CAPI3REF: Error Codes And Messages
drh6ed48bf2007-06-14 20:57:18 +00002257**
drhd68eee02009-12-11 03:44:18 +00002258** ^The sqlite3_errcode() interface returns the numeric [result code] or
mihailimefc8e8a2008-06-21 16:47:09 +00002259** [extended result code] for the most recent failed sqlite3_* API call
2260** associated with a [database connection]. If a prior API call failed
2261** but the most recent API call succeeded, the return value from
drhd68eee02009-12-11 03:44:18 +00002262** sqlite3_errcode() is undefined. ^The sqlite3_extended_errcode()
drh99dfe5e2008-10-30 15:03:15 +00002263** interface is the same except that it always returns the
2264** [extended result code] even when extended result codes are
2265** disabled.
drh6ed48bf2007-06-14 20:57:18 +00002266**
drhd68eee02009-12-11 03:44:18 +00002267** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
mihailimebe796c2008-06-21 20:11:17 +00002268** text that describes the error, as either UTF-8 or UTF-16 respectively.
drhd68eee02009-12-11 03:44:18 +00002269** ^(Memory to hold the error message string is managed internally.
mihailimefc8e8a2008-06-21 16:47:09 +00002270** The application does not need to worry about freeing the result.
mlcreech27358862008-03-01 23:34:46 +00002271** However, the error string might be overwritten or deallocated by
drhd68eee02009-12-11 03:44:18 +00002272** subsequent calls to other SQLite interface functions.)^
danielk197765904932004-05-26 06:18:37 +00002273**
drh2838b472008-11-04 14:48:22 +00002274** When the serialized [threading mode] is in use, it might be the
2275** case that a second error occurs on a separate thread in between
2276** the time of the first error and the call to these interfaces.
2277** When that happens, the second error will be reported since these
2278** interfaces always report the most recent result. To avoid
2279** this, each thread can obtain exclusive use of the [database connection] D
2280** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
2281** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
2282** all calls to the interfaces listed here are completed.
2283**
drhd55d57e2008-07-07 17:53:07 +00002284** If an interface fails with SQLITE_MISUSE, that means the interface
2285** was invoked incorrectly by the application. In that case, the
2286** error code and message may or may not be set.
danielk197765904932004-05-26 06:18:37 +00002287*/
2288int sqlite3_errcode(sqlite3 *db);
drh99dfe5e2008-10-30 15:03:15 +00002289int sqlite3_extended_errcode(sqlite3 *db);
danielk197765904932004-05-26 06:18:37 +00002290const char *sqlite3_errmsg(sqlite3*);
danielk197765904932004-05-26 06:18:37 +00002291const void *sqlite3_errmsg16(sqlite3*);
2292
2293/*
drhd68eee02009-12-11 03:44:18 +00002294** CAPI3REF: SQL Statement Object
drh33c1be32008-01-30 16:16:14 +00002295** KEYWORDS: {prepared statement} {prepared statements}
drh6ed48bf2007-06-14 20:57:18 +00002296**
mihailimefc8e8a2008-06-21 16:47:09 +00002297** An instance of this object represents a single SQL statement.
2298** This object is variously known as a "prepared statement" or a
drh6ed48bf2007-06-14 20:57:18 +00002299** "compiled SQL statement" or simply as a "statement".
mihailimefc8e8a2008-06-21 16:47:09 +00002300**
drh6ed48bf2007-06-14 20:57:18 +00002301** The life of a statement object goes something like this:
2302**
2303** <ol>
2304** <li> Create the object using [sqlite3_prepare_v2()] or a related
2305** function.
mihailimefc8e8a2008-06-21 16:47:09 +00002306** <li> Bind values to [host parameters] using the sqlite3_bind_*()
2307** interfaces.
drh6ed48bf2007-06-14 20:57:18 +00002308** <li> Run the SQL by calling [sqlite3_step()] one or more times.
2309** <li> Reset the statement using [sqlite3_reset()] then go back
2310** to step 2. Do this zero or more times.
2311** <li> Destroy the object using [sqlite3_finalize()].
2312** </ol>
2313**
2314** Refer to documentation on individual methods above for additional
2315** information.
danielk197765904932004-05-26 06:18:37 +00002316*/
danielk1977fc57d7b2004-05-26 02:04:57 +00002317typedef struct sqlite3_stmt sqlite3_stmt;
2318
danielk1977e3209e42004-05-20 01:40:18 +00002319/*
drhd68eee02009-12-11 03:44:18 +00002320** CAPI3REF: Run-time Limits
drhcaa639f2008-03-20 00:32:20 +00002321**
drhd68eee02009-12-11 03:44:18 +00002322** ^(This interface allows the size of various constructs to be limited
drhcaa639f2008-03-20 00:32:20 +00002323** on a connection by connection basis. The first parameter is the
2324** [database connection] whose limit is to be set or queried. The
2325** second parameter is one of the [limit categories] that define a
2326** class of constructs to be size limited. The third parameter is the
drhd68eee02009-12-11 03:44:18 +00002327** new limit for that construct. The function returns the old limit.)^
drhcaa639f2008-03-20 00:32:20 +00002328**
drhd68eee02009-12-11 03:44:18 +00002329** ^If the new limit is a negative number, the limit is unchanged.
2330** ^(For the limit category of SQLITE_LIMIT_XYZ there is a
drhae1a8802009-02-11 15:04:40 +00002331** [limits | hard upper bound]
2332** set by a compile-time C preprocessor macro named
2333** [limits | SQLITE_MAX_XYZ].
drhd68eee02009-12-11 03:44:18 +00002334** (The "_LIMIT_" in the name is changed to "_MAX_".))^
2335** ^Attempts to increase a limit above its hard upper bound are
drh7a98b852009-12-13 23:03:01 +00002336** silently truncated to the hard upper bound.
drhcaa639f2008-03-20 00:32:20 +00002337**
drhd68eee02009-12-11 03:44:18 +00002338** Run-time limits are intended for use in applications that manage
drhbb4957f2008-03-20 14:03:29 +00002339** both their own internal database and also databases that are controlled
2340** by untrusted external sources. An example application might be a
drh46f33ef2009-02-11 15:23:35 +00002341** web browser that has its own databases for storing history and
shane26b34032008-05-23 17:21:09 +00002342** separate databases controlled by JavaScript applications downloaded
shane236ce972008-05-30 15:35:30 +00002343** off the Internet. The internal databases can be given the
drhbb4957f2008-03-20 14:03:29 +00002344** large, default limits. Databases managed by external sources can
2345** be given much smaller limits designed to prevent a denial of service
mihailimefc8e8a2008-06-21 16:47:09 +00002346** attack. Developers might also want to use the [sqlite3_set_authorizer()]
drhf47ce562008-03-20 18:00:49 +00002347** interface to further control untrusted SQL. The size of the database
2348** created by an untrusted script can be contained using the
2349** [max_page_count] [PRAGMA].
drhbb4957f2008-03-20 14:03:29 +00002350**
drha911abe2008-07-16 13:29:51 +00002351** New run-time limit categories may be added in future releases.
drhcaa639f2008-03-20 00:32:20 +00002352*/
2353int sqlite3_limit(sqlite3*, int id, int newVal);
2354
2355/*
drhd68eee02009-12-11 03:44:18 +00002356** CAPI3REF: Run-Time Limit Categories
drhe7ae4e22009-11-02 15:51:52 +00002357** KEYWORDS: {limit category} {*limit categories}
mihailimefc8e8a2008-06-21 16:47:09 +00002358**
drh46f33ef2009-02-11 15:23:35 +00002359** These constants define various performance limits
2360** that can be lowered at run-time using [sqlite3_limit()].
2361** The synopsis of the meanings of the various limits is shown below.
2362** Additional information is available at [limits | Limits in SQLite].
drhbb4957f2008-03-20 14:03:29 +00002363**
2364** <dl>
drhd68eee02009-12-11 03:44:18 +00002365** ^(<dt>SQLITE_LIMIT_LENGTH</dt>
2366** <dd>The maximum size of any string or BLOB or table row.<dd>)^
drhbb4957f2008-03-20 14:03:29 +00002367**
drhd68eee02009-12-11 03:44:18 +00002368** ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
drhdf6473a2009-12-13 22:20:08 +00002369** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002370**
drhd68eee02009-12-11 03:44:18 +00002371** ^(<dt>SQLITE_LIMIT_COLUMN</dt>
drhbb4957f2008-03-20 14:03:29 +00002372** <dd>The maximum number of columns in a table definition or in the
drh46f33ef2009-02-11 15:23:35 +00002373** result set of a [SELECT] or the maximum number of columns in an index
drhd68eee02009-12-11 03:44:18 +00002374** or in an ORDER BY or GROUP BY clause.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002375**
drhd68eee02009-12-11 03:44:18 +00002376** ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
2377** <dd>The maximum depth of the parse tree on any expression.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002378**
drhd68eee02009-12-11 03:44:18 +00002379** ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
2380** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002381**
drhd68eee02009-12-11 03:44:18 +00002382** ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
drhbb4957f2008-03-20 14:03:29 +00002383** <dd>The maximum number of instructions in a virtual machine program
drhd68eee02009-12-11 03:44:18 +00002384** used to implement an SQL statement.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002385**
drhd68eee02009-12-11 03:44:18 +00002386** ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
2387** <dd>The maximum number of arguments on a function.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002388**
drhd68eee02009-12-11 03:44:18 +00002389** ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
drh7a98b852009-12-13 23:03:01 +00002390** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
drhbb4957f2008-03-20 14:03:29 +00002391**
drh7a98b852009-12-13 23:03:01 +00002392** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
drh46f33ef2009-02-11 15:23:35 +00002393** <dd>The maximum length of the pattern argument to the [LIKE] or
drhd68eee02009-12-11 03:44:18 +00002394** [GLOB] operators.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002395**
drhd68eee02009-12-11 03:44:18 +00002396** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
drhbb4957f2008-03-20 14:03:29 +00002397** <dd>The maximum number of variables in an SQL statement that can
drhd68eee02009-12-11 03:44:18 +00002398** be bound.</dd>)^
drh417168a2009-09-07 18:14:02 +00002399**
drhd68eee02009-12-11 03:44:18 +00002400** ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
2401** <dd>The maximum depth of recursion for triggers.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002402** </dl>
drhcaa639f2008-03-20 00:32:20 +00002403*/
2404#define SQLITE_LIMIT_LENGTH 0
2405#define SQLITE_LIMIT_SQL_LENGTH 1
2406#define SQLITE_LIMIT_COLUMN 2
2407#define SQLITE_LIMIT_EXPR_DEPTH 3
2408#define SQLITE_LIMIT_COMPOUND_SELECT 4
2409#define SQLITE_LIMIT_VDBE_OP 5
2410#define SQLITE_LIMIT_FUNCTION_ARG 6
2411#define SQLITE_LIMIT_ATTACHED 7
drhb1a6c3c2008-03-20 16:30:17 +00002412#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
2413#define SQLITE_LIMIT_VARIABLE_NUMBER 9
drh417168a2009-09-07 18:14:02 +00002414#define SQLITE_LIMIT_TRIGGER_DEPTH 10
drhcaa639f2008-03-20 00:32:20 +00002415
2416/*
drhd68eee02009-12-11 03:44:18 +00002417** CAPI3REF: Compiling An SQL Statement
mihailimefc8e8a2008-06-21 16:47:09 +00002418** KEYWORDS: {SQL statement compiler}
danielk197765904932004-05-26 06:18:37 +00002419**
drh6ed48bf2007-06-14 20:57:18 +00002420** To execute an SQL query, it must first be compiled into a byte-code
mihailimefc8e8a2008-06-21 16:47:09 +00002421** program using one of these routines.
drh6ed48bf2007-06-14 20:57:18 +00002422**
mihailimefc8e8a2008-06-21 16:47:09 +00002423** The first argument, "db", is a [database connection] obtained from a
drh860e0772009-04-02 18:32:26 +00002424** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
2425** [sqlite3_open16()]. The database connection must not have been closed.
mihailimefc8e8a2008-06-21 16:47:09 +00002426**
2427** The second argument, "zSql", is the statement to be compiled, encoded
drh6ed48bf2007-06-14 20:57:18 +00002428** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
mihailimefc8e8a2008-06-21 16:47:09 +00002429** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
mihailim04bcc002008-06-22 10:21:27 +00002430** use UTF-16.
drh21f06722007-07-19 12:41:39 +00002431**
drhd68eee02009-12-11 03:44:18 +00002432** ^If the nByte argument is less than zero, then zSql is read up to the
2433** first zero terminator. ^If nByte is non-negative, then it is the maximum
2434** number of bytes read from zSql. ^When nByte is non-negative, the
mihailimefc8e8a2008-06-21 16:47:09 +00002435** zSql string ends at either the first '\000' or '\u0000' character or
drhb08c2a72008-04-16 00:28:13 +00002436** the nByte-th byte, whichever comes first. If the caller knows
danielk19773a2c8c82008-04-03 14:36:25 +00002437** that the supplied string is nul-terminated, then there is a small
mihailimefc8e8a2008-06-21 16:47:09 +00002438** performance advantage to be gained by passing an nByte parameter that
2439** is equal to the number of bytes in the input string <i>including</i>
mihailim04bcc002008-06-22 10:21:27 +00002440** the nul-terminator bytes.
danielk197765904932004-05-26 06:18:37 +00002441**
drhd68eee02009-12-11 03:44:18 +00002442** ^If pzTail is not NULL then *pzTail is made to point to the first byte
drh860e0772009-04-02 18:32:26 +00002443** past the end of the first SQL statement in zSql. These routines only
2444** compile the first statement in zSql, so *pzTail is left pointing to
2445** what remains uncompiled.
danielk197765904932004-05-26 06:18:37 +00002446**
drhd68eee02009-12-11 03:44:18 +00002447** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
2448** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
2449** to NULL. ^If the input text contains no SQL (if the input is an empty
mihailimefc8e8a2008-06-21 16:47:09 +00002450** string or a comment) then *ppStmt is set to NULL.
drh860e0772009-04-02 18:32:26 +00002451** The calling procedure is responsible for deleting the compiled
mihailimefc8e8a2008-06-21 16:47:09 +00002452** SQL statement using [sqlite3_finalize()] after it has finished with it.
drh860e0772009-04-02 18:32:26 +00002453** ppStmt may not be NULL.
danielk197765904932004-05-26 06:18:37 +00002454**
drhd68eee02009-12-11 03:44:18 +00002455** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
2456** otherwise an [error code] is returned.
drh6ed48bf2007-06-14 20:57:18 +00002457**
2458** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
2459** recommended for all new programs. The two older interfaces are retained
2460** for backwards compatibility, but their use is discouraged.
drhd68eee02009-12-11 03:44:18 +00002461** ^In the "v2" interfaces, the prepared statement
mihailimefc8e8a2008-06-21 16:47:09 +00002462** that is returned (the [sqlite3_stmt] object) contains a copy of the
mihailim04bcc002008-06-22 10:21:27 +00002463** original SQL text. This causes the [sqlite3_step()] interface to
drh481aa742009-11-05 18:46:02 +00002464** behave differently in three ways:
drh6ed48bf2007-06-14 20:57:18 +00002465**
2466** <ol>
drh33c1be32008-01-30 16:16:14 +00002467** <li>
drhd68eee02009-12-11 03:44:18 +00002468** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
drh6ed48bf2007-06-14 20:57:18 +00002469** always used to do, [sqlite3_step()] will automatically recompile the SQL
drhd68eee02009-12-11 03:44:18 +00002470** statement and try to run it again. ^If the schema has changed in
drhfddfa2d2007-12-05 18:05:16 +00002471** a way that makes the statement no longer valid, [sqlite3_step()] will still
mihailimefc8e8a2008-06-21 16:47:09 +00002472** return [SQLITE_SCHEMA]. But unlike the legacy behavior, [SQLITE_SCHEMA] is
2473** now a fatal error. Calling [sqlite3_prepare_v2()] again will not make the
drh33c1be32008-01-30 16:16:14 +00002474** error go away. Note: use [sqlite3_errmsg()] to find the text
mihailim04bcc002008-06-22 10:21:27 +00002475** of the parsing error that results in an [SQLITE_SCHEMA] return.
drh6ed48bf2007-06-14 20:57:18 +00002476** </li>
2477**
2478** <li>
drhd68eee02009-12-11 03:44:18 +00002479** ^When an error occurs, [sqlite3_step()] will return one of the detailed
2480** [error codes] or [extended error codes]. ^The legacy behavior was that
mihailimefc8e8a2008-06-21 16:47:09 +00002481** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
drhdf6473a2009-12-13 22:20:08 +00002482** and the application would have to make a second call to [sqlite3_reset()]
2483** in order to find the underlying cause of the problem. With the "v2" prepare
mihailimefc8e8a2008-06-21 16:47:09 +00002484** interfaces, the underlying reason for the error is returned immediately.
drh6ed48bf2007-06-14 20:57:18 +00002485** </li>
drh4b5af772009-10-20 14:08:41 +00002486**
2487** <li>
2488** ^If the value of a [parameter | host parameter] in the WHERE clause might
2489** change the query plan for a statement, then the statement may be
2490** automatically recompiled (as if there had been a schema change) on the first
2491** [sqlite3_step()] call following any change to the
2492** [sqlite3_bind_text | bindings] of the [parameter].
2493** </li>
drh6ed48bf2007-06-14 20:57:18 +00002494** </ol>
danielk197765904932004-05-26 06:18:37 +00002495*/
2496int sqlite3_prepare(
2497 sqlite3 *db, /* Database handle */
2498 const char *zSql, /* SQL statement, UTF-8 encoded */
drh21f06722007-07-19 12:41:39 +00002499 int nByte, /* Maximum length of zSql in bytes. */
danielk197765904932004-05-26 06:18:37 +00002500 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2501 const char **pzTail /* OUT: Pointer to unused portion of zSql */
2502);
drh6ed48bf2007-06-14 20:57:18 +00002503int sqlite3_prepare_v2(
2504 sqlite3 *db, /* Database handle */
2505 const char *zSql, /* SQL statement, UTF-8 encoded */
drh21f06722007-07-19 12:41:39 +00002506 int nByte, /* Maximum length of zSql in bytes. */
drh6ed48bf2007-06-14 20:57:18 +00002507 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2508 const char **pzTail /* OUT: Pointer to unused portion of zSql */
2509);
danielk197765904932004-05-26 06:18:37 +00002510int sqlite3_prepare16(
2511 sqlite3 *db, /* Database handle */
2512 const void *zSql, /* SQL statement, UTF-16 encoded */
drh21f06722007-07-19 12:41:39 +00002513 int nByte, /* Maximum length of zSql in bytes. */
danielk197765904932004-05-26 06:18:37 +00002514 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2515 const void **pzTail /* OUT: Pointer to unused portion of zSql */
2516);
drhb900aaf2006-11-09 00:24:53 +00002517int sqlite3_prepare16_v2(
2518 sqlite3 *db, /* Database handle */
2519 const void *zSql, /* SQL statement, UTF-16 encoded */
drh21f06722007-07-19 12:41:39 +00002520 int nByte, /* Maximum length of zSql in bytes. */
drhb900aaf2006-11-09 00:24:53 +00002521 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2522 const void **pzTail /* OUT: Pointer to unused portion of zSql */
2523);
2524
2525/*
drhd68eee02009-12-11 03:44:18 +00002526** CAPI3REF: Retrieving Statement SQL
danielk1977d0e2a852007-11-14 06:48:48 +00002527**
drhd68eee02009-12-11 03:44:18 +00002528** ^This interface can be used to retrieve a saved copy of the original
mihailimefc8e8a2008-06-21 16:47:09 +00002529** SQL text used to create a [prepared statement] if that statement was
2530** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
danielk1977d0e2a852007-11-14 06:48:48 +00002531*/
2532const char *sqlite3_sql(sqlite3_stmt *pStmt);
2533
2534/*
drhd68eee02009-12-11 03:44:18 +00002535** CAPI3REF: Dynamically Typed Value Object
drhaa28e142008-03-18 13:47:20 +00002536** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
drh6ed48bf2007-06-14 20:57:18 +00002537**
drh33c1be32008-01-30 16:16:14 +00002538** SQLite uses the sqlite3_value object to represent all values
mihailimefc8e8a2008-06-21 16:47:09 +00002539** that can be stored in a database table. SQLite uses dynamic typing
drhd68eee02009-12-11 03:44:18 +00002540** for the values it stores. ^Values stored in sqlite3_value objects
mihailimefc8e8a2008-06-21 16:47:09 +00002541** can be integers, floating point values, strings, BLOBs, or NULL.
drhaa28e142008-03-18 13:47:20 +00002542**
2543** An sqlite3_value object may be either "protected" or "unprotected".
2544** Some interfaces require a protected sqlite3_value. Other interfaces
2545** will accept either a protected or an unprotected sqlite3_value.
mihailimefc8e8a2008-06-21 16:47:09 +00002546** Every interface that accepts sqlite3_value arguments specifies
drhaa28e142008-03-18 13:47:20 +00002547** whether or not it requires a protected sqlite3_value.
2548**
2549** The terms "protected" and "unprotected" refer to whether or not
2550** a mutex is held. A internal mutex is held for a protected
2551** sqlite3_value object but no mutex is held for an unprotected
2552** sqlite3_value object. If SQLite is compiled to be single-threaded
drh4766b292008-06-26 02:53:02 +00002553** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
drh4ead1482008-06-26 18:16:05 +00002554** or if SQLite is run in one of reduced mutex modes
2555** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
mihailimefc8e8a2008-06-21 16:47:09 +00002556** then there is no distinction between protected and unprotected
2557** sqlite3_value objects and they can be used interchangeably. However,
2558** for maximum code portability it is recommended that applications
2559** still make the distinction between between protected and unprotected
drh4ead1482008-06-26 18:16:05 +00002560** sqlite3_value objects even when not strictly required.
drhaa28e142008-03-18 13:47:20 +00002561**
drhd68eee02009-12-11 03:44:18 +00002562** ^The sqlite3_value objects that are passed as parameters into the
mihailimefc8e8a2008-06-21 16:47:09 +00002563** implementation of [application-defined SQL functions] are protected.
drhd68eee02009-12-11 03:44:18 +00002564** ^The sqlite3_value object returned by
drhaa28e142008-03-18 13:47:20 +00002565** [sqlite3_column_value()] is unprotected.
2566** Unprotected sqlite3_value objects may only be used with
mihailimefc8e8a2008-06-21 16:47:09 +00002567** [sqlite3_result_value()] and [sqlite3_bind_value()].
drhce5a5a02008-06-10 17:41:44 +00002568** The [sqlite3_value_blob | sqlite3_value_type()] family of
2569** interfaces require protected sqlite3_value objects.
drhf4479502004-05-27 03:12:53 +00002570*/
drhf4479502004-05-27 03:12:53 +00002571typedef struct Mem sqlite3_value;
2572
2573/*
drhfb434032009-12-11 23:11:26 +00002574** CAPI3REF: SQL Function Context Object
drh4f26d6c2004-05-26 23:25:30 +00002575**
drh6ed48bf2007-06-14 20:57:18 +00002576** The context in which an SQL function executes is stored in an
drhd68eee02009-12-11 03:44:18 +00002577** sqlite3_context object. ^A pointer to an sqlite3_context object
mihailimefc8e8a2008-06-21 16:47:09 +00002578** is always first parameter to [application-defined SQL functions].
2579** The application-defined SQL function implementation will pass this
2580** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
2581** [sqlite3_aggregate_context()], [sqlite3_user_data()],
2582** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
2583** and/or [sqlite3_set_auxdata()].
drh6ed48bf2007-06-14 20:57:18 +00002584*/
2585typedef struct sqlite3_context sqlite3_context;
2586
2587/*
drhfb434032009-12-11 23:11:26 +00002588** CAPI3REF: Binding Values To Prepared Statements
mihailimefc8e8a2008-06-21 16:47:09 +00002589** KEYWORDS: {host parameter} {host parameters} {host parameter name}
mihailimebe796c2008-06-21 20:11:17 +00002590** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
drh6ed48bf2007-06-14 20:57:18 +00002591**
drhd68eee02009-12-11 03:44:18 +00002592** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
drh333ceb92009-08-25 14:59:37 +00002593** literals may be replaced by a [parameter] that matches one of following
2594** templates:
drh6ed48bf2007-06-14 20:57:18 +00002595**
2596** <ul>
2597** <li> ?
2598** <li> ?NNN
drh33c1be32008-01-30 16:16:14 +00002599** <li> :VVV
2600** <li> @VVV
drh6ed48bf2007-06-14 20:57:18 +00002601** <li> $VVV
2602** </ul>
2603**
drh333ceb92009-08-25 14:59:37 +00002604** In the templates above, NNN represents an integer literal,
drhd68eee02009-12-11 03:44:18 +00002605** and VVV represents an alphanumeric identifer.)^ ^The values of these
mihailimefc8e8a2008-06-21 16:47:09 +00002606** parameters (also called "host parameter names" or "SQL parameters")
drh6ed48bf2007-06-14 20:57:18 +00002607** can be set using the sqlite3_bind_*() routines defined here.
2608**
drhd68eee02009-12-11 03:44:18 +00002609** ^The first argument to the sqlite3_bind_*() routines is always
mihailimefc8e8a2008-06-21 16:47:09 +00002610** a pointer to the [sqlite3_stmt] object returned from
2611** [sqlite3_prepare_v2()] or its variants.
2612**
drhd68eee02009-12-11 03:44:18 +00002613** ^The second argument is the index of the SQL parameter to be set.
2614** ^The leftmost SQL parameter has an index of 1. ^When the same named
mihailimefc8e8a2008-06-21 16:47:09 +00002615** SQL parameter is used more than once, second and subsequent
2616** occurrences have the same index as the first occurrence.
drhd68eee02009-12-11 03:44:18 +00002617** ^The index for named parameters can be looked up using the
2618** [sqlite3_bind_parameter_index()] API if desired. ^The index
drhf5befa02007-12-06 02:42:07 +00002619** for "?NNN" parameters is the value of NNN.
drhd68eee02009-12-11 03:44:18 +00002620** ^The NNN value must be between 1 and the [sqlite3_limit()]
drh4ead1482008-06-26 18:16:05 +00002621** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
drh6ed48bf2007-06-14 20:57:18 +00002622**
drhd68eee02009-12-11 03:44:18 +00002623** ^The third argument is the value to bind to the parameter.
drh6ed48bf2007-06-14 20:57:18 +00002624**
drhd68eee02009-12-11 03:44:18 +00002625** ^(In those routines that have a fourth argument, its value is the
mihailimefc8e8a2008-06-21 16:47:09 +00002626** number of bytes in the parameter. To be clear: the value is the
drhd68eee02009-12-11 03:44:18 +00002627** number of <u>bytes</u> in the value, not the number of characters.)^
2628** ^If the fourth parameter is negative, the length of the string is
shane26b34032008-05-23 17:21:09 +00002629** the number of bytes up to the first zero terminator.
drh4f26d6c2004-05-26 23:25:30 +00002630**
drhd68eee02009-12-11 03:44:18 +00002631** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
drh900dfba2004-07-21 15:21:36 +00002632** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
drhd68eee02009-12-11 03:44:18 +00002633** string after SQLite has finished with it. ^If the fifth argument is
drh33c1be32008-01-30 16:16:14 +00002634** the special value [SQLITE_STATIC], then SQLite assumes that the
drhfddfa2d2007-12-05 18:05:16 +00002635** information is in static, unmanaged space and does not need to be freed.
drhd68eee02009-12-11 03:44:18 +00002636** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
drhfddfa2d2007-12-05 18:05:16 +00002637** SQLite makes its own private copy of the data immediately, before
drh33c1be32008-01-30 16:16:14 +00002638** the sqlite3_bind_*() routine returns.
drh4f26d6c2004-05-26 23:25:30 +00002639**
drhd68eee02009-12-11 03:44:18 +00002640** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
2641** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
mihailimefc8e8a2008-06-21 16:47:09 +00002642** (just an integer to hold its size) while it is being processed.
shane26b34032008-05-23 17:21:09 +00002643** Zeroblobs are intended to serve as placeholders for BLOBs whose
mihailimefc8e8a2008-06-21 16:47:09 +00002644** content is later written using
2645** [sqlite3_blob_open | incremental BLOB I/O] routines.
drhd68eee02009-12-11 03:44:18 +00002646** ^A negative value for the zeroblob results in a zero-length BLOB.
drh6ed48bf2007-06-14 20:57:18 +00002647**
drhd68eee02009-12-11 03:44:18 +00002648** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
2649** for the [prepared statement] or with a prepared statement for which
2650** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
2651** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
2652** routine is passed a [prepared statement] that has been finalized, the
2653** result is undefined and probably harmful.
drh6ed48bf2007-06-14 20:57:18 +00002654**
drhd68eee02009-12-11 03:44:18 +00002655** ^Bindings are not cleared by the [sqlite3_reset()] routine.
2656** ^Unbound parameters are interpreted as NULL.
2657**
2658** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
2659** [error code] if anything goes wrong.
2660** ^[SQLITE_RANGE] is returned if the parameter
2661** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
drh33c1be32008-01-30 16:16:14 +00002662**
2663** See also: [sqlite3_bind_parameter_count()],
mihailimefc8e8a2008-06-21 16:47:09 +00002664** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
drh4f26d6c2004-05-26 23:25:30 +00002665*/
danielk1977d8123362004-06-12 09:25:12 +00002666int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
drhf4479502004-05-27 03:12:53 +00002667int sqlite3_bind_double(sqlite3_stmt*, int, double);
2668int sqlite3_bind_int(sqlite3_stmt*, int, int);
drh6d2069d2007-08-14 01:58:53 +00002669int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
drhf4479502004-05-27 03:12:53 +00002670int sqlite3_bind_null(sqlite3_stmt*, int);
danielk1977d8123362004-06-12 09:25:12 +00002671int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
2672int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
drhf4479502004-05-27 03:12:53 +00002673int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
drhb026e052007-05-02 01:34:31 +00002674int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
drh4f26d6c2004-05-26 23:25:30 +00002675
2676/*
drhd68eee02009-12-11 03:44:18 +00002677** CAPI3REF: Number Of SQL Parameters
drh6ed48bf2007-06-14 20:57:18 +00002678**
drhd68eee02009-12-11 03:44:18 +00002679** ^This routine can be used to find the number of [SQL parameters]
mihailimefc8e8a2008-06-21 16:47:09 +00002680** in a [prepared statement]. SQL parameters are tokens of the
drh33c1be32008-01-30 16:16:14 +00002681** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
shane26b34032008-05-23 17:21:09 +00002682** placeholders for values that are [sqlite3_bind_blob | bound]
drh33c1be32008-01-30 16:16:14 +00002683** to the parameters at a later time.
drh605264d2007-08-21 15:13:19 +00002684**
drhd68eee02009-12-11 03:44:18 +00002685** ^(This routine actually returns the index of the largest (rightmost)
mihailimefc8e8a2008-06-21 16:47:09 +00002686** parameter. For all forms except ?NNN, this will correspond to the
drhd68eee02009-12-11 03:44:18 +00002687** number of unique parameters. If parameters of the ?NNN form are used,
2688** there may be gaps in the list.)^
drh33c1be32008-01-30 16:16:14 +00002689**
2690** See also: [sqlite3_bind_blob|sqlite3_bind()],
2691** [sqlite3_bind_parameter_name()], and
2692** [sqlite3_bind_parameter_index()].
drh75f6a032004-07-15 14:15:00 +00002693*/
2694int sqlite3_bind_parameter_count(sqlite3_stmt*);
2695
2696/*
drhd68eee02009-12-11 03:44:18 +00002697** CAPI3REF: Name Of A Host Parameter
drh6ed48bf2007-06-14 20:57:18 +00002698**
drhd68eee02009-12-11 03:44:18 +00002699** ^The sqlite3_bind_parameter_name(P,N) interface returns
2700** the name of the N-th [SQL parameter] in the [prepared statement] P.
2701** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
drhe1b3e802008-04-27 22:29:01 +00002702** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
2703** respectively.
2704** In other words, the initial ":" or "$" or "@" or "?"
drhd68eee02009-12-11 03:44:18 +00002705** is included as part of the name.)^
2706** ^Parameters of the form "?" without a following integer have no name
drhdf6473a2009-12-13 22:20:08 +00002707** and are referred to as "nameless" or "anonymous parameters".
drh6ed48bf2007-06-14 20:57:18 +00002708**
drhd68eee02009-12-11 03:44:18 +00002709** ^The first host parameter has an index of 1, not 0.
drh6ed48bf2007-06-14 20:57:18 +00002710**
drhd68eee02009-12-11 03:44:18 +00002711** ^If the value N is out of range or if the N-th parameter is
2712** nameless, then NULL is returned. ^The returned string is
mihailimefc8e8a2008-06-21 16:47:09 +00002713** always in UTF-8 encoding even if the named parameter was
drhfddfa2d2007-12-05 18:05:16 +00002714** originally specified as UTF-16 in [sqlite3_prepare16()] or
2715** [sqlite3_prepare16_v2()].
drh33c1be32008-01-30 16:16:14 +00002716**
2717** See also: [sqlite3_bind_blob|sqlite3_bind()],
2718** [sqlite3_bind_parameter_count()], and
2719** [sqlite3_bind_parameter_index()].
drh895d7472004-08-20 16:02:39 +00002720*/
2721const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
2722
2723/*
drhd68eee02009-12-11 03:44:18 +00002724** CAPI3REF: Index Of A Parameter With A Given Name
drh6ed48bf2007-06-14 20:57:18 +00002725**
drhd68eee02009-12-11 03:44:18 +00002726** ^Return the index of an SQL parameter given its name. ^The
drh33c1be32008-01-30 16:16:14 +00002727** index value returned is suitable for use as the second
drhd68eee02009-12-11 03:44:18 +00002728** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
2729** is returned if no matching parameter is found. ^The parameter
drh33c1be32008-01-30 16:16:14 +00002730** name must be given in UTF-8 even if the original statement
2731** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
2732**
2733** See also: [sqlite3_bind_blob|sqlite3_bind()],
2734** [sqlite3_bind_parameter_count()], and
2735** [sqlite3_bind_parameter_index()].
drhfa6bc002004-09-07 16:19:52 +00002736*/
2737int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
2738
2739/*
drhd68eee02009-12-11 03:44:18 +00002740** CAPI3REF: Reset All Bindings On A Prepared Statement
drh6ed48bf2007-06-14 20:57:18 +00002741**
drhd68eee02009-12-11 03:44:18 +00002742** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
mihailimefc8e8a2008-06-21 16:47:09 +00002743** the [sqlite3_bind_blob | bindings] on a [prepared statement].
drhd68eee02009-12-11 03:44:18 +00002744** ^Use this routine to reset all host parameters to NULL.
danielk1977600dd0b2005-01-20 01:14:23 +00002745*/
2746int sqlite3_clear_bindings(sqlite3_stmt*);
2747
2748/*
drhd68eee02009-12-11 03:44:18 +00002749** CAPI3REF: Number Of Columns In A Result Set
drh6ed48bf2007-06-14 20:57:18 +00002750**
drhd68eee02009-12-11 03:44:18 +00002751** ^Return the number of columns in the result set returned by the
2752** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
drh4ead1482008-06-26 18:16:05 +00002753** statement that does not return data (for example an [UPDATE]).
danielk197765904932004-05-26 06:18:37 +00002754*/
2755int sqlite3_column_count(sqlite3_stmt *pStmt);
2756
2757/*
drhd68eee02009-12-11 03:44:18 +00002758** CAPI3REF: Column Names In A Result Set
drh6ed48bf2007-06-14 20:57:18 +00002759**
drhd68eee02009-12-11 03:44:18 +00002760** ^These routines return the name assigned to a particular column
2761** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
mihailimefc8e8a2008-06-21 16:47:09 +00002762** interface returns a pointer to a zero-terminated UTF-8 string
drhf5befa02007-12-06 02:42:07 +00002763** and sqlite3_column_name16() returns a pointer to a zero-terminated
drhd68eee02009-12-11 03:44:18 +00002764** UTF-16 string. ^The first parameter is the [prepared statement]
2765** that implements the [SELECT] statement. ^The second parameter is the
2766** column number. ^The leftmost column is number 0.
drh6ed48bf2007-06-14 20:57:18 +00002767**
drhd68eee02009-12-11 03:44:18 +00002768** ^The returned string pointer is valid until either the [prepared statement]
mihailimefc8e8a2008-06-21 16:47:09 +00002769** is destroyed by [sqlite3_finalize()] or until the next call to
2770** sqlite3_column_name() or sqlite3_column_name16() on the same column.
drh4a50aac2007-08-23 02:47:53 +00002771**
drhd68eee02009-12-11 03:44:18 +00002772** ^If sqlite3_malloc() fails during the processing of either routine
drh4a50aac2007-08-23 02:47:53 +00002773** (for example during a conversion from UTF-8 to UTF-16) then a
2774** NULL pointer is returned.
drh33c1be32008-01-30 16:16:14 +00002775**
drhd68eee02009-12-11 03:44:18 +00002776** ^The name of a result column is the value of the "AS" clause for
drh33c1be32008-01-30 16:16:14 +00002777** that column, if there is an AS clause. If there is no AS clause
2778** then the name of the column is unspecified and may change from
2779** one release of SQLite to the next.
danielk197765904932004-05-26 06:18:37 +00002780*/
drh6ed48bf2007-06-14 20:57:18 +00002781const char *sqlite3_column_name(sqlite3_stmt*, int N);
2782const void *sqlite3_column_name16(sqlite3_stmt*, int N);
danielk197765904932004-05-26 06:18:37 +00002783
2784/*
drhd68eee02009-12-11 03:44:18 +00002785** CAPI3REF: Source Of Data In A Query Result
drh6ed48bf2007-06-14 20:57:18 +00002786**
drh9be37f62009-12-12 23:57:36 +00002787** ^These routines provide a means to determine the database, table, and
2788** table column that is the origin of a particular result column in
2789** [SELECT] statement.
drhd68eee02009-12-11 03:44:18 +00002790** ^The name of the database or table or column can be returned as
2791** either a UTF-8 or UTF-16 string. ^The _database_ routines return
drhbf2564f2007-06-21 15:25:05 +00002792** the database name, the _table_ routines return the table name, and
drh33c1be32008-01-30 16:16:14 +00002793** the origin_ routines return the column name.
drhd68eee02009-12-11 03:44:18 +00002794** ^The returned string is valid until the [prepared statement] is destroyed
mihailim1c492652008-06-21 18:02:16 +00002795** using [sqlite3_finalize()] or until the same information is requested
drhbf2564f2007-06-21 15:25:05 +00002796** again in a different encoding.
2797**
drhd68eee02009-12-11 03:44:18 +00002798** ^The names returned are the original un-aliased names of the
drhbf2564f2007-06-21 15:25:05 +00002799** database, table, and column.
drh6ed48bf2007-06-14 20:57:18 +00002800**
drh9be37f62009-12-12 23:57:36 +00002801** ^The first argument to these interfaces is a [prepared statement].
2802** ^These functions return information about the Nth result column returned by
danielk1977955de522006-02-10 02:27:42 +00002803** the statement, where N is the second function argument.
drh9be37f62009-12-12 23:57:36 +00002804** ^The left-most column is column 0 for these routines.
danielk1977955de522006-02-10 02:27:42 +00002805**
drhd68eee02009-12-11 03:44:18 +00002806** ^If the Nth column returned by the statement is an expression or
mihailim1c492652008-06-21 18:02:16 +00002807** subquery and is not a column value, then all of these functions return
drhd68eee02009-12-11 03:44:18 +00002808** NULL. ^These routine might also return NULL if a memory allocation error
drhdf6473a2009-12-13 22:20:08 +00002809** occurs. ^Otherwise, they return the name of the attached database, table,
drhd68eee02009-12-11 03:44:18 +00002810** or column that query result column was extracted from.
danielk1977955de522006-02-10 02:27:42 +00002811**
drh9be37f62009-12-12 23:57:36 +00002812** ^As with all other SQLite APIs, those whose names end with "16" return
2813** UTF-16 encoded strings and the other functions return UTF-8.
danielk19774b1ae992006-02-10 03:06:10 +00002814**
drhd68eee02009-12-11 03:44:18 +00002815** ^These APIs are only available if the library was compiled with the
drh9be37f62009-12-12 23:57:36 +00002816** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
drh32bc3f62007-08-21 20:25:39 +00002817**
2818** If two or more threads call one or more of these routines against the same
2819** prepared statement and column at the same time then the results are
2820** undefined.
drh33c1be32008-01-30 16:16:14 +00002821**
drh8b39db12009-02-18 18:37:58 +00002822** If two or more threads call one or more
2823** [sqlite3_column_database_name | column metadata interfaces]
2824** for the same [prepared statement] and result column
2825** at the same time then the results are undefined.
danielk1977955de522006-02-10 02:27:42 +00002826*/
2827const char *sqlite3_column_database_name(sqlite3_stmt*,int);
2828const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
2829const char *sqlite3_column_table_name(sqlite3_stmt*,int);
2830const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
2831const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
2832const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
2833
2834/*
drhd68eee02009-12-11 03:44:18 +00002835** CAPI3REF: Declared Datatype Of A Query Result
drh6ed48bf2007-06-14 20:57:18 +00002836**
drhd68eee02009-12-11 03:44:18 +00002837** ^(The first parameter is a [prepared statement].
drh4ead1482008-06-26 18:16:05 +00002838** If this statement is a [SELECT] statement and the Nth column of the
2839** returned result set of that [SELECT] is a table column (not an
drh6ed48bf2007-06-14 20:57:18 +00002840** expression or subquery) then the declared type of the table
drhdf6473a2009-12-13 22:20:08 +00002841** column is returned.)^ ^If the Nth column of the result set is an
drh6ed48bf2007-06-14 20:57:18 +00002842** expression or subquery, then a NULL pointer is returned.
drhd68eee02009-12-11 03:44:18 +00002843** ^The returned string is always UTF-8 encoded.
mihailim1c492652008-06-21 18:02:16 +00002844**
drhd68eee02009-12-11 03:44:18 +00002845** ^(For example, given the database schema:
danielk197765904932004-05-26 06:18:37 +00002846**
2847** CREATE TABLE t1(c1 VARIANT);
2848**
mihailim1c492652008-06-21 18:02:16 +00002849** and the following statement to be compiled:
danielk197765904932004-05-26 06:18:37 +00002850**
danielk1977955de522006-02-10 02:27:42 +00002851** SELECT c1 + 1, c1 FROM t1;
danielk197765904932004-05-26 06:18:37 +00002852**
mihailim1c492652008-06-21 18:02:16 +00002853** this routine would return the string "VARIANT" for the second result
drhd68eee02009-12-11 03:44:18 +00002854** column (i==1), and a NULL pointer for the first result column (i==0).)^
drh6ed48bf2007-06-14 20:57:18 +00002855**
drhd68eee02009-12-11 03:44:18 +00002856** ^SQLite uses dynamic run-time typing. ^So just because a column
drh6ed48bf2007-06-14 20:57:18 +00002857** is declared to contain a particular type does not mean that the
2858** data stored in that column is of the declared type. SQLite is
drhd68eee02009-12-11 03:44:18 +00002859** strongly typed, but the typing is dynamic not static. ^Type
drh6ed48bf2007-06-14 20:57:18 +00002860** is associated with individual values, not with the containers
2861** used to hold those values.
danielk197765904932004-05-26 06:18:37 +00002862*/
drh33c1be32008-01-30 16:16:14 +00002863const char *sqlite3_column_decltype(sqlite3_stmt*,int);
danielk197765904932004-05-26 06:18:37 +00002864const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
2865
mihailimebe796c2008-06-21 20:11:17 +00002866/*
drhd68eee02009-12-11 03:44:18 +00002867** CAPI3REF: Evaluate An SQL Statement
danielk1977106bb232004-05-21 10:08:53 +00002868**
mihailim1c492652008-06-21 18:02:16 +00002869** After a [prepared statement] has been prepared using either
2870** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
2871** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
2872** must be called one or more times to evaluate the statement.
danielk1977106bb232004-05-21 10:08:53 +00002873**
mihailim1c492652008-06-21 18:02:16 +00002874** The details of the behavior of the sqlite3_step() interface depend
drh6ed48bf2007-06-14 20:57:18 +00002875** on whether the statement was prepared using the newer "v2" interface
2876** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
2877** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
2878** new "v2" interface is recommended for new applications but the legacy
2879** interface will continue to be supported.
danielk1977106bb232004-05-21 10:08:53 +00002880**
drhd68eee02009-12-11 03:44:18 +00002881** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
drh6ed48bf2007-06-14 20:57:18 +00002882** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
drhd68eee02009-12-11 03:44:18 +00002883** ^With the "v2" interface, any of the other [result codes] or
mihailim1c492652008-06-21 18:02:16 +00002884** [extended result codes] might be returned as well.
drh6ed48bf2007-06-14 20:57:18 +00002885**
drhd68eee02009-12-11 03:44:18 +00002886** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
2887** database locks it needs to do its job. ^If the statement is a [COMMIT]
drh6ed48bf2007-06-14 20:57:18 +00002888** or occurs outside of an explicit transaction, then you can retry the
drh4ead1482008-06-26 18:16:05 +00002889** statement. If the statement is not a [COMMIT] and occurs within a
drh6ed48bf2007-06-14 20:57:18 +00002890** explicit transaction then you should rollback the transaction before
2891** continuing.
2892**
drhd68eee02009-12-11 03:44:18 +00002893** ^[SQLITE_DONE] means that the statement has finished executing
danielk1977106bb232004-05-21 10:08:53 +00002894** successfully. sqlite3_step() should not be called again on this virtual
drh6ed48bf2007-06-14 20:57:18 +00002895** machine without first calling [sqlite3_reset()] to reset the virtual
2896** machine back to its initial state.
danielk1977106bb232004-05-21 10:08:53 +00002897**
drhd68eee02009-12-11 03:44:18 +00002898** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
mihailim1c492652008-06-21 18:02:16 +00002899** is returned each time a new row of data is ready for processing by the
2900** caller. The values may be accessed using the [column access functions].
drh6ed48bf2007-06-14 20:57:18 +00002901** sqlite3_step() is called again to retrieve the next row of data.
mihailim1c492652008-06-21 18:02:16 +00002902**
drhd68eee02009-12-11 03:44:18 +00002903** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
danielk1977106bb232004-05-21 10:08:53 +00002904** violation) has occurred. sqlite3_step() should not be called again on
drh6ed48bf2007-06-14 20:57:18 +00002905** the VM. More information may be found by calling [sqlite3_errmsg()].
drhd68eee02009-12-11 03:44:18 +00002906** ^With the legacy interface, a more specific error code (for example,
drh6ed48bf2007-06-14 20:57:18 +00002907** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
2908** can be obtained by calling [sqlite3_reset()] on the
drhd68eee02009-12-11 03:44:18 +00002909** [prepared statement]. ^In the "v2" interface,
drh6ed48bf2007-06-14 20:57:18 +00002910** the more specific error code is returned directly by sqlite3_step().
danielk1977106bb232004-05-21 10:08:53 +00002911**
drh6ed48bf2007-06-14 20:57:18 +00002912** [SQLITE_MISUSE] means that the this routine was called inappropriately.
drh33c1be32008-01-30 16:16:14 +00002913** Perhaps it was called on a [prepared statement] that has
mihailim1c492652008-06-21 18:02:16 +00002914** already been [sqlite3_finalize | finalized] or on one that had
drh6ed48bf2007-06-14 20:57:18 +00002915** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
2916** be the case that the same database connection is being used by two or
2917** more threads at the same moment in time.
2918**
drh3674bfd2010-04-17 12:53:19 +00002919** For all versions of SQLite up to and including 3.6.23.1, it was required
2920** after sqlite3_step() returned anything other than [SQLITE_ROW] that
2921** [sqlite3_reset()] be called before any subsequent invocation of
2922** sqlite3_step(). Failure to invoke [sqlite3_reset()] in this way would
2923** result in an [SQLITE_MISUSE] return from sqlite3_step(). But after
2924** version 3.6.23.1, sqlite3_step() began calling [sqlite3_reset()]
2925** automatically in this circumstance rather than returning [SQLITE_MISUSE].
2926**
mihailim1c492652008-06-21 18:02:16 +00002927** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
2928** API always returns a generic error code, [SQLITE_ERROR], following any
2929** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
2930** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
2931** specific [error codes] that better describes the error.
drh6ed48bf2007-06-14 20:57:18 +00002932** We admit that this is a goofy design. The problem has been fixed
2933** with the "v2" interface. If you prepare all of your SQL statements
2934** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
mihailim1c492652008-06-21 18:02:16 +00002935** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
2936** then the more specific [error codes] are returned directly
drh6ed48bf2007-06-14 20:57:18 +00002937** by sqlite3_step(). The use of the "v2" interface is recommended.
danielk1977106bb232004-05-21 10:08:53 +00002938*/
danielk197717240fd2004-05-26 00:07:25 +00002939int sqlite3_step(sqlite3_stmt*);
danielk1977106bb232004-05-21 10:08:53 +00002940
danielk1977106bb232004-05-21 10:08:53 +00002941/*
drhd68eee02009-12-11 03:44:18 +00002942** CAPI3REF: Number of columns in a result set
drh6ed48bf2007-06-14 20:57:18 +00002943**
drhfb434032009-12-11 23:11:26 +00002944** ^The sqlite3_data_count(P) the number of columns in the
2945** of the result set of [prepared statement] P.
danielk1977106bb232004-05-21 10:08:53 +00002946*/
danielk197793d46752004-05-23 13:30:58 +00002947int sqlite3_data_count(sqlite3_stmt *pStmt);
danielk19774adee202004-05-08 08:23:19 +00002948
drh4f26d6c2004-05-26 23:25:30 +00002949/*
drhd68eee02009-12-11 03:44:18 +00002950** CAPI3REF: Fundamental Datatypes
drh33c1be32008-01-30 16:16:14 +00002951** KEYWORDS: SQLITE_TEXT
drh6ed48bf2007-06-14 20:57:18 +00002952**
drhfb434032009-12-11 23:11:26 +00002953** ^(Every value in SQLite has one of five fundamental datatypes:
drh6ed48bf2007-06-14 20:57:18 +00002954**
2955** <ul>
2956** <li> 64-bit signed integer
2957** <li> 64-bit IEEE floating point number
2958** <li> string
2959** <li> BLOB
2960** <li> NULL
drhfb434032009-12-11 23:11:26 +00002961** </ul>)^
drh6ed48bf2007-06-14 20:57:18 +00002962**
2963** These constants are codes for each of those types.
2964**
2965** Note that the SQLITE_TEXT constant was also used in SQLite version 2
2966** for a completely different meaning. Software that links against both
mihailim1c492652008-06-21 18:02:16 +00002967** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
drh6ed48bf2007-06-14 20:57:18 +00002968** SQLITE_TEXT.
drh4f26d6c2004-05-26 23:25:30 +00002969*/
drh9c054832004-05-31 18:51:57 +00002970#define SQLITE_INTEGER 1
2971#define SQLITE_FLOAT 2
drh9c054832004-05-31 18:51:57 +00002972#define SQLITE_BLOB 4
2973#define SQLITE_NULL 5
drh1e284f42004-10-06 15:52:01 +00002974#ifdef SQLITE_TEXT
2975# undef SQLITE_TEXT
2976#else
2977# define SQLITE_TEXT 3
2978#endif
2979#define SQLITE3_TEXT 3
2980
2981/*
drhd68eee02009-12-11 03:44:18 +00002982** CAPI3REF: Result Values From A Query
mihailim1c492652008-06-21 18:02:16 +00002983** KEYWORDS: {column access functions}
drh6ed48bf2007-06-14 20:57:18 +00002984**
drhd68eee02009-12-11 03:44:18 +00002985** These routines form the "result set" interface.
drh33c1be32008-01-30 16:16:14 +00002986**
drhd68eee02009-12-11 03:44:18 +00002987** ^These routines return information about a single column of the current
2988** result row of a query. ^In every case the first argument is a pointer
mihailim1c492652008-06-21 18:02:16 +00002989** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
2990** that was returned from [sqlite3_prepare_v2()] or one of its variants)
2991** and the second argument is the index of the column for which information
drhd68eee02009-12-11 03:44:18 +00002992** should be returned. ^The leftmost column of the result set has the index 0.
2993** ^The number of columns in the result can be determined using
drhedc17552009-10-22 00:14:05 +00002994** [sqlite3_column_count()].
danielk1977106bb232004-05-21 10:08:53 +00002995**
mihailim1c492652008-06-21 18:02:16 +00002996** If the SQL statement does not currently point to a valid row, or if the
2997** column index is out of range, the result is undefined.
drh32bc3f62007-08-21 20:25:39 +00002998** These routines may only be called when the most recent call to
2999** [sqlite3_step()] has returned [SQLITE_ROW] and neither
mihailim1c492652008-06-21 18:02:16 +00003000** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
drh32bc3f62007-08-21 20:25:39 +00003001** If any of these routines are called after [sqlite3_reset()] or
3002** [sqlite3_finalize()] or after [sqlite3_step()] has returned
3003** something other than [SQLITE_ROW], the results are undefined.
3004** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
3005** are called from a different thread while any of these routines
mihailim1c492652008-06-21 18:02:16 +00003006** are pending, then the results are undefined.
drh6ed48bf2007-06-14 20:57:18 +00003007**
drhd68eee02009-12-11 03:44:18 +00003008** ^The sqlite3_column_type() routine returns the
drh6ed48bf2007-06-14 20:57:18 +00003009** [SQLITE_INTEGER | datatype code] for the initial data type
drhd68eee02009-12-11 03:44:18 +00003010** of the result column. ^The returned value is one of [SQLITE_INTEGER],
drh6ed48bf2007-06-14 20:57:18 +00003011** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
3012** returned by sqlite3_column_type() is only meaningful if no type
3013** conversions have occurred as described below. After a type conversion,
3014** the value returned by sqlite3_column_type() is undefined. Future
3015** versions of SQLite may change the behavior of sqlite3_column_type()
3016** following a type conversion.
3017**
drhd68eee02009-12-11 03:44:18 +00003018** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
drh6ed48bf2007-06-14 20:57:18 +00003019** routine returns the number of bytes in that BLOB or string.
drhd68eee02009-12-11 03:44:18 +00003020** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
drh6ed48bf2007-06-14 20:57:18 +00003021** the string to UTF-8 and then returns the number of bytes.
drhd68eee02009-12-11 03:44:18 +00003022** ^If the result is a numeric value then sqlite3_column_bytes() uses
mihailimebe796c2008-06-21 20:11:17 +00003023** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
drh6ed48bf2007-06-14 20:57:18 +00003024** the number of bytes in that string.
drhd68eee02009-12-11 03:44:18 +00003025** ^The value returned does not include the zero terminator at the end
3026** of the string. ^For clarity: the value returned is the number of
drh6ed48bf2007-06-14 20:57:18 +00003027** bytes in the string, not the number of characters.
3028**
drhd68eee02009-12-11 03:44:18 +00003029** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
3030** even empty strings, are always zero terminated. ^The return
mihailim04bcc002008-06-22 10:21:27 +00003031** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
drhc0b3abb2007-09-04 12:18:41 +00003032** pointer, possibly even a NULL pointer.
3033**
drhd68eee02009-12-11 03:44:18 +00003034** ^The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
mihailim1c492652008-06-21 18:02:16 +00003035** but leaves the result in UTF-16 in native byte order instead of UTF-8.
drhd68eee02009-12-11 03:44:18 +00003036** ^The zero terminator is not included in this count.
drh4f26d6c2004-05-26 23:25:30 +00003037**
drhd68eee02009-12-11 03:44:18 +00003038** ^The object returned by [sqlite3_column_value()] is an
drhaa28e142008-03-18 13:47:20 +00003039** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
3040** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
3041** If the [unprotected sqlite3_value] object returned by
3042** [sqlite3_column_value()] is used in any other way, including calls
mihailim1c492652008-06-21 18:02:16 +00003043** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
3044** or [sqlite3_value_bytes()], then the behavior is undefined.
drhaa28e142008-03-18 13:47:20 +00003045**
drhd68eee02009-12-11 03:44:18 +00003046** These routines attempt to convert the value where appropriate. ^For
drh4f26d6c2004-05-26 23:25:30 +00003047** example, if the internal representation is FLOAT and a text result
mihailim1c492652008-06-21 18:02:16 +00003048** is requested, [sqlite3_snprintf()] is used internally to perform the
drhd68eee02009-12-11 03:44:18 +00003049** conversion automatically. ^(The following table details the conversions
mihailim1c492652008-06-21 18:02:16 +00003050** that are applied:
drh4f26d6c2004-05-26 23:25:30 +00003051**
drh6ed48bf2007-06-14 20:57:18 +00003052** <blockquote>
3053** <table border="1">
drh8bacf972007-08-25 16:21:29 +00003054** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
drh4f26d6c2004-05-26 23:25:30 +00003055**
drh6ed48bf2007-06-14 20:57:18 +00003056** <tr><td> NULL <td> INTEGER <td> Result is 0
3057** <tr><td> NULL <td> FLOAT <td> Result is 0.0
3058** <tr><td> NULL <td> TEXT <td> Result is NULL pointer
3059** <tr><td> NULL <td> BLOB <td> Result is NULL pointer
3060** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
3061** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
mihailim1c492652008-06-21 18:02:16 +00003062** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
drh6ed48bf2007-06-14 20:57:18 +00003063** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer
3064** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
3065** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT
3066** <tr><td> TEXT <td> INTEGER <td> Use atoi()
3067** <tr><td> TEXT <td> FLOAT <td> Use atof()
3068** <tr><td> TEXT <td> BLOB <td> No change
3069** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi()
3070** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof()
3071** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
3072** </table>
drhd68eee02009-12-11 03:44:18 +00003073** </blockquote>)^
drh4f26d6c2004-05-26 23:25:30 +00003074**
drh6ed48bf2007-06-14 20:57:18 +00003075** The table above makes reference to standard C library functions atoi()
3076** and atof(). SQLite does not really use these functions. It has its
shane26b34032008-05-23 17:21:09 +00003077** own equivalent internal routines. The atoi() and atof() names are
drh6ed48bf2007-06-14 20:57:18 +00003078** used in the table for brevity and because they are familiar to most
3079** C programmers.
3080**
drhd68eee02009-12-11 03:44:18 +00003081** ^Note that when type conversions occur, pointers returned by prior
drh6ed48bf2007-06-14 20:57:18 +00003082** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
mihailim1c492652008-06-21 18:02:16 +00003083** sqlite3_column_text16() may be invalidated.
drhd68eee02009-12-11 03:44:18 +00003084** ^(Type conversions and pointer invalidations might occur
drh6ed48bf2007-06-14 20:57:18 +00003085** in the following cases:
3086**
3087** <ul>
mihailim1c492652008-06-21 18:02:16 +00003088** <li> The initial content is a BLOB and sqlite3_column_text() or
3089** sqlite3_column_text16() is called. A zero-terminator might
3090** need to be added to the string.</li>
3091** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
3092** sqlite3_column_text16() is called. The content must be converted
3093** to UTF-16.</li>
3094** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
3095** sqlite3_column_text() is called. The content must be converted
3096** to UTF-8.</li>
drhd68eee02009-12-11 03:44:18 +00003097** </ul>)^
drh6ed48bf2007-06-14 20:57:18 +00003098**
drhd68eee02009-12-11 03:44:18 +00003099** ^Conversions between UTF-16be and UTF-16le are always done in place and do
drh6ed48bf2007-06-14 20:57:18 +00003100** not invalidate a prior pointer, though of course the content of the buffer
3101** that the prior pointer points to will have been modified. Other kinds
mihailim1c492652008-06-21 18:02:16 +00003102** of conversion are done in place when it is possible, but sometimes they
3103** are not possible and in those cases prior pointers are invalidated.
drh6ed48bf2007-06-14 20:57:18 +00003104**
drhd68eee02009-12-11 03:44:18 +00003105** ^(The safest and easiest to remember policy is to invoke these routines
drh6ed48bf2007-06-14 20:57:18 +00003106** in one of the following ways:
3107**
mihailim1c492652008-06-21 18:02:16 +00003108** <ul>
drh6ed48bf2007-06-14 20:57:18 +00003109** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
3110** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
3111** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
drhd68eee02009-12-11 03:44:18 +00003112** </ul>)^
drh6ed48bf2007-06-14 20:57:18 +00003113**
mihailim1c492652008-06-21 18:02:16 +00003114** In other words, you should call sqlite3_column_text(),
3115** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
3116** into the desired format, then invoke sqlite3_column_bytes() or
3117** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
3118** to sqlite3_column_text() or sqlite3_column_blob() with calls to
3119** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
3120** with calls to sqlite3_column_bytes().
drh32bc3f62007-08-21 20:25:39 +00003121**
drhd68eee02009-12-11 03:44:18 +00003122** ^The pointers returned are valid until a type conversion occurs as
drh32bc3f62007-08-21 20:25:39 +00003123** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
drhd68eee02009-12-11 03:44:18 +00003124** [sqlite3_finalize()] is called. ^The memory space used to hold strings
mihailim04bcc002008-06-22 10:21:27 +00003125** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned
mihailim1c492652008-06-21 18:02:16 +00003126** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
drh32bc3f62007-08-21 20:25:39 +00003127** [sqlite3_free()].
drh4a50aac2007-08-23 02:47:53 +00003128**
drhd68eee02009-12-11 03:44:18 +00003129** ^(If a memory allocation error occurs during the evaluation of any
drh4a50aac2007-08-23 02:47:53 +00003130** of these routines, a default value is returned. The default value
3131** is either the integer 0, the floating point number 0.0, or a NULL
3132** pointer. Subsequent calls to [sqlite3_errcode()] will return
drhd68eee02009-12-11 03:44:18 +00003133** [SQLITE_NOMEM].)^
danielk1977106bb232004-05-21 10:08:53 +00003134*/
drhf4479502004-05-27 03:12:53 +00003135const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
3136int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
3137int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
3138double sqlite3_column_double(sqlite3_stmt*, int iCol);
3139int sqlite3_column_int(sqlite3_stmt*, int iCol);
drh6d2069d2007-08-14 01:58:53 +00003140sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
drhf4479502004-05-27 03:12:53 +00003141const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
3142const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
drh4f26d6c2004-05-26 23:25:30 +00003143int sqlite3_column_type(sqlite3_stmt*, int iCol);
drh4be8b512006-06-13 23:51:34 +00003144sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
danielk19774adee202004-05-08 08:23:19 +00003145
danielk197765904932004-05-26 06:18:37 +00003146/*
drhd68eee02009-12-11 03:44:18 +00003147** CAPI3REF: Destroy A Prepared Statement Object
drh6ed48bf2007-06-14 20:57:18 +00003148**
drhd68eee02009-12-11 03:44:18 +00003149** ^The sqlite3_finalize() function is called to delete a [prepared statement].
3150** ^If the statement was executed successfully or not executed at all, then
3151** SQLITE_OK is returned. ^If execution of the statement failed then an
mihailimebe796c2008-06-21 20:11:17 +00003152** [error code] or [extended error code] is returned.
danielk197765904932004-05-26 06:18:37 +00003153**
drhd68eee02009-12-11 03:44:18 +00003154** ^This routine can be called at any point during the execution of the
3155** [prepared statement]. ^If the virtual machine has not
drh6ed48bf2007-06-14 20:57:18 +00003156** completed execution when this routine is called, that is like
mihailimebe796c2008-06-21 20:11:17 +00003157** encountering an error or an [sqlite3_interrupt | interrupt].
drhd68eee02009-12-11 03:44:18 +00003158** ^Incomplete updates may be rolled back and transactions canceled,
mihailimebe796c2008-06-21 20:11:17 +00003159** depending on the circumstances, and the
drh33c1be32008-01-30 16:16:14 +00003160** [error code] returned will be [SQLITE_ABORT].
danielk197765904932004-05-26 06:18:37 +00003161*/
3162int sqlite3_finalize(sqlite3_stmt *pStmt);
3163
3164/*
drhd68eee02009-12-11 03:44:18 +00003165** CAPI3REF: Reset A Prepared Statement Object
drh6ed48bf2007-06-14 20:57:18 +00003166**
mihailimebe796c2008-06-21 20:11:17 +00003167** The sqlite3_reset() function is called to reset a [prepared statement]
3168** object back to its initial state, ready to be re-executed.
drhd68eee02009-12-11 03:44:18 +00003169** ^Any SQL statement variables that had values bound to them using
drh6ed48bf2007-06-14 20:57:18 +00003170** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
3171** Use [sqlite3_clear_bindings()] to reset the bindings.
drh33c1be32008-01-30 16:16:14 +00003172**
drhd68eee02009-12-11 03:44:18 +00003173** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
3174** back to the beginning of its program.
drh33c1be32008-01-30 16:16:14 +00003175**
drhd68eee02009-12-11 03:44:18 +00003176** ^If the most recent call to [sqlite3_step(S)] for the
3177** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
3178** or if [sqlite3_step(S)] has never before been called on S,
3179** then [sqlite3_reset(S)] returns [SQLITE_OK].
drh33c1be32008-01-30 16:16:14 +00003180**
drhd68eee02009-12-11 03:44:18 +00003181** ^If the most recent call to [sqlite3_step(S)] for the
3182** [prepared statement] S indicated an error, then
3183** [sqlite3_reset(S)] returns an appropriate [error code].
drh33c1be32008-01-30 16:16:14 +00003184**
drhd68eee02009-12-11 03:44:18 +00003185** ^The [sqlite3_reset(S)] interface does not change the values
3186** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
danielk197765904932004-05-26 06:18:37 +00003187*/
3188int sqlite3_reset(sqlite3_stmt *pStmt);
3189
3190/*
drhd68eee02009-12-11 03:44:18 +00003191** CAPI3REF: Create Or Redefine SQL Functions
mihailimefc8e8a2008-06-21 16:47:09 +00003192** KEYWORDS: {function creation routines}
3193** KEYWORDS: {application-defined SQL function}
3194** KEYWORDS: {application-defined SQL functions}
drh6ed48bf2007-06-14 20:57:18 +00003195**
drhd68eee02009-12-11 03:44:18 +00003196** ^These two functions (collectively known as "function creation routines")
mihailimebe796c2008-06-21 20:11:17 +00003197** are used to add SQL functions or aggregates or to redefine the behavior
3198** of existing SQL functions or aggregates. The only difference between the
3199** two is that the second parameter, the name of the (scalar) function or
3200** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
3201** for sqlite3_create_function16().
danielk197765904932004-05-26 06:18:37 +00003202**
drhdf6473a2009-12-13 22:20:08 +00003203** ^The first parameter is the [database connection] to which the SQL
3204** function is to be added. ^If an application uses more than one database
3205** connection then application-defined SQL functions must be added
3206** to each database connection separately.
danielk197765904932004-05-26 06:18:37 +00003207**
mihailimebe796c2008-06-21 20:11:17 +00003208** The second parameter is the name of the SQL function to be created or
drhd68eee02009-12-11 03:44:18 +00003209** redefined. ^The length of the name is limited to 255 bytes, exclusive of
mihailimebe796c2008-06-21 20:11:17 +00003210** the zero-terminator. Note that the name length limit is in bytes, not
drhd68eee02009-12-11 03:44:18 +00003211** characters. ^Any attempt to create a function with a longer name
mihailimebe796c2008-06-21 20:11:17 +00003212** will result in [SQLITE_ERROR] being returned.
drh6ed48bf2007-06-14 20:57:18 +00003213**
drhd68eee02009-12-11 03:44:18 +00003214** ^The third parameter (nArg)
drhc8075422008-09-10 13:09:23 +00003215** is the number of arguments that the SQL function or
drhd68eee02009-12-11 03:44:18 +00003216** aggregate takes. ^If this parameter is -1, then the SQL function or
drh97602f82009-05-24 11:07:49 +00003217** aggregate may take any number of arguments between 0 and the limit
3218** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
drh09943b52009-05-24 21:59:27 +00003219** parameter is less than -1 or greater than 127 then the behavior is
3220** undefined.
danielk197765904932004-05-26 06:18:37 +00003221**
mihailimebe796c2008-06-21 20:11:17 +00003222** The fourth parameter, eTextRep, specifies what
drh6ed48bf2007-06-14 20:57:18 +00003223** [SQLITE_UTF8 | text encoding] this SQL function prefers for
3224** its parameters. Any SQL function implementation should be able to work
3225** work with UTF-8, UTF-16le, or UTF-16be. But some implementations may be
drhd68eee02009-12-11 03:44:18 +00003226** more efficient with one encoding than another. ^An application may
drh6d2069d2007-08-14 01:58:53 +00003227** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
drh6ed48bf2007-06-14 20:57:18 +00003228** times with the same function but with different values of eTextRep.
drhd68eee02009-12-11 03:44:18 +00003229** ^When multiple implementations of the same function are available, SQLite
drh6ed48bf2007-06-14 20:57:18 +00003230** will pick the one that involves the least amount of data conversion.
mihailimebe796c2008-06-21 20:11:17 +00003231** If there is only a single implementation which does not care what text
3232** encoding is used, then the fourth argument should be [SQLITE_ANY].
drh6ed48bf2007-06-14 20:57:18 +00003233**
drhd68eee02009-12-11 03:44:18 +00003234** ^(The fifth parameter is an arbitrary pointer. The implementation of the
3235** function can gain access to this pointer using [sqlite3_user_data()].)^
danielk1977d02eb1f2004-06-06 09:44:03 +00003236**
danielk197765904932004-05-26 06:18:37 +00003237** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
mihailimebe796c2008-06-21 20:11:17 +00003238** pointers to C-language functions that implement the SQL function or
drhd68eee02009-12-11 03:44:18 +00003239** aggregate. ^A scalar SQL function requires an implementation of the xFunc
3240** callback only; NULL pointers should be passed as the xStep and xFinal
3241** parameters. ^An aggregate SQL function requires an implementation of xStep
3242** and xFinal and NULL should be passed for xFunc. ^To delete an existing
mihailimebe796c2008-06-21 20:11:17 +00003243** SQL function or aggregate, pass NULL for all three function callbacks.
drh6ed48bf2007-06-14 20:57:18 +00003244**
drhd68eee02009-12-11 03:44:18 +00003245** ^It is permitted to register multiple implementations of the same
drh6ed48bf2007-06-14 20:57:18 +00003246** functions with the same name but with either differing numbers of
drhd68eee02009-12-11 03:44:18 +00003247** arguments or differing preferred text encodings. ^SQLite will use
drh6aa5f152009-08-19 15:57:07 +00003248** the implementation that most closely matches the way in which the
drhd68eee02009-12-11 03:44:18 +00003249** SQL function is used. ^A function implementation with a non-negative
drhc8075422008-09-10 13:09:23 +00003250** nArg parameter is a better match than a function implementation with
drhd68eee02009-12-11 03:44:18 +00003251** a negative nArg. ^A function where the preferred text encoding
drhc8075422008-09-10 13:09:23 +00003252** matches the database encoding is a better
3253** match than a function where the encoding is different.
drhd68eee02009-12-11 03:44:18 +00003254** ^A function where the encoding difference is between UTF16le and UTF16be
drhc8075422008-09-10 13:09:23 +00003255** is a closer match than a function where the encoding difference is
3256** between UTF8 and UTF16.
3257**
drhd68eee02009-12-11 03:44:18 +00003258** ^Built-in functions may be overloaded by new application-defined functions.
3259** ^The first application-defined function with a given name overrides all
drhc8075422008-09-10 13:09:23 +00003260** built-in functions in the same [database connection] with the same name.
drhd68eee02009-12-11 03:44:18 +00003261** ^Subsequent application-defined functions of the same name only override
drhc8075422008-09-10 13:09:23 +00003262** prior application-defined functions that are an exact match for the
3263** number of parameters and preferred encoding.
3264**
drhd68eee02009-12-11 03:44:18 +00003265** ^An application-defined function is permitted to call other
drhc8075422008-09-10 13:09:23 +00003266** SQLite interfaces. However, such calls must not
3267** close the database connection nor finalize or reset the prepared
3268** statement in which the function is running.
danielk197765904932004-05-26 06:18:37 +00003269*/
3270int sqlite3_create_function(
drh33c1be32008-01-30 16:16:14 +00003271 sqlite3 *db,
danielk197765904932004-05-26 06:18:37 +00003272 const char *zFunctionName,
3273 int nArg,
3274 int eTextRep,
drh33c1be32008-01-30 16:16:14 +00003275 void *pApp,
danielk197765904932004-05-26 06:18:37 +00003276 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
3277 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
3278 void (*xFinal)(sqlite3_context*)
3279);
3280int sqlite3_create_function16(
drh33c1be32008-01-30 16:16:14 +00003281 sqlite3 *db,
danielk197765904932004-05-26 06:18:37 +00003282 const void *zFunctionName,
3283 int nArg,
3284 int eTextRep,
drh33c1be32008-01-30 16:16:14 +00003285 void *pApp,
danielk197765904932004-05-26 06:18:37 +00003286 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
3287 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
3288 void (*xFinal)(sqlite3_context*)
3289);
3290
3291/*
drhd68eee02009-12-11 03:44:18 +00003292** CAPI3REF: Text Encodings
drh6ed48bf2007-06-14 20:57:18 +00003293**
3294** These constant define integer codes that represent the various
3295** text encodings supported by SQLite.
danielk197765904932004-05-26 06:18:37 +00003296*/
drh6ed48bf2007-06-14 20:57:18 +00003297#define SQLITE_UTF8 1
3298#define SQLITE_UTF16LE 2
3299#define SQLITE_UTF16BE 3
3300#define SQLITE_UTF16 4 /* Use native byte order */
3301#define SQLITE_ANY 5 /* sqlite3_create_function only */
3302#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
danielk197765904932004-05-26 06:18:37 +00003303
danielk19770ffba6b2004-05-24 09:10:10 +00003304/*
drhd5a68d32008-08-04 13:44:57 +00003305** CAPI3REF: Deprecated Functions
3306** DEPRECATED
drh6ed48bf2007-06-14 20:57:18 +00003307**
drhd5a68d32008-08-04 13:44:57 +00003308** These functions are [deprecated]. In order to maintain
3309** backwards compatibility with older code, these functions continue
3310** to be supported. However, new applications should avoid
drh6ed48bf2007-06-14 20:57:18 +00003311** the use of these functions. To help encourage people to avoid
shane7ba429a2008-11-10 17:08:49 +00003312** using these functions, we are not going to tell you what they do.
drh6ed48bf2007-06-14 20:57:18 +00003313*/
shaneeec556d2008-10-12 00:27:53 +00003314#ifndef SQLITE_OMIT_DEPRECATED
shanea79c3cc2008-08-11 17:27:01 +00003315SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
3316SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
3317SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
3318SQLITE_DEPRECATED int sqlite3_global_recover(void);
3319SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
3320SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
shaneeec556d2008-10-12 00:27:53 +00003321#endif
drh6ed48bf2007-06-14 20:57:18 +00003322
3323/*
drhd68eee02009-12-11 03:44:18 +00003324** CAPI3REF: Obtaining SQL Function Parameter Values
drh6ed48bf2007-06-14 20:57:18 +00003325**
3326** The C-language implementation of SQL functions and aggregates uses
3327** this set of interface routines to access the parameter values on
3328** the function or aggregate.
3329**
3330** The xFunc (for scalar functions) or xStep (for aggregates) parameters
3331** to [sqlite3_create_function()] and [sqlite3_create_function16()]
3332** define callbacks that implement the SQL functions and aggregates.
3333** The 4th parameter to these callbacks is an array of pointers to
drhaa28e142008-03-18 13:47:20 +00003334** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
drh6ed48bf2007-06-14 20:57:18 +00003335** each parameter to the SQL function. These routines are used to
3336** extract values from the [sqlite3_value] objects.
3337**
drhaa28e142008-03-18 13:47:20 +00003338** These routines work only with [protected sqlite3_value] objects.
3339** Any attempt to use these routines on an [unprotected sqlite3_value]
3340** object results in undefined behavior.
3341**
drhd68eee02009-12-11 03:44:18 +00003342** ^These routines work just like the corresponding [column access functions]
mihailim1c492652008-06-21 18:02:16 +00003343** except that these routines take a single [protected sqlite3_value] object
3344** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
drh6ed48bf2007-06-14 20:57:18 +00003345**
drhd68eee02009-12-11 03:44:18 +00003346** ^The sqlite3_value_text16() interface extracts a UTF-16 string
3347** in the native byte-order of the host machine. ^The
drh6ed48bf2007-06-14 20:57:18 +00003348** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
mihailimebe796c2008-06-21 20:11:17 +00003349** extract UTF-16 strings as big-endian and little-endian respectively.
drh6ed48bf2007-06-14 20:57:18 +00003350**
drhd68eee02009-12-11 03:44:18 +00003351** ^(The sqlite3_value_numeric_type() interface attempts to apply
drh6ed48bf2007-06-14 20:57:18 +00003352** numeric affinity to the value. This means that an attempt is
3353** made to convert the value to an integer or floating point. If
drhf5befa02007-12-06 02:42:07 +00003354** such a conversion is possible without loss of information (in other
mihailimebe796c2008-06-21 20:11:17 +00003355** words, if the value is a string that looks like a number)
3356** then the conversion is performed. Otherwise no conversion occurs.
drhd68eee02009-12-11 03:44:18 +00003357** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
drh6ed48bf2007-06-14 20:57:18 +00003358**
mihailimebe796c2008-06-21 20:11:17 +00003359** Please pay particular attention to the fact that the pointer returned
3360** from [sqlite3_value_blob()], [sqlite3_value_text()], or
drh6ed48bf2007-06-14 20:57:18 +00003361** [sqlite3_value_text16()] can be invalidated by a subsequent call to
drh6d2069d2007-08-14 01:58:53 +00003362** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
mihailimebe796c2008-06-21 20:11:17 +00003363** or [sqlite3_value_text16()].
drhe53831d2007-08-17 01:14:38 +00003364**
3365** These routines must be called from the same thread as
drhaa28e142008-03-18 13:47:20 +00003366** the SQL function that supplied the [sqlite3_value*] parameters.
danielk19770ffba6b2004-05-24 09:10:10 +00003367*/
drhf4479502004-05-27 03:12:53 +00003368const void *sqlite3_value_blob(sqlite3_value*);
3369int sqlite3_value_bytes(sqlite3_value*);
3370int sqlite3_value_bytes16(sqlite3_value*);
3371double sqlite3_value_double(sqlite3_value*);
3372int sqlite3_value_int(sqlite3_value*);
drh6d2069d2007-08-14 01:58:53 +00003373sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
drhf4479502004-05-27 03:12:53 +00003374const unsigned char *sqlite3_value_text(sqlite3_value*);
3375const void *sqlite3_value_text16(sqlite3_value*);
danielk1977d8123362004-06-12 09:25:12 +00003376const void *sqlite3_value_text16le(sqlite3_value*);
3377const void *sqlite3_value_text16be(sqlite3_value*);
danielk197793d46752004-05-23 13:30:58 +00003378int sqlite3_value_type(sqlite3_value*);
drh29d72102006-02-09 22:13:41 +00003379int sqlite3_value_numeric_type(sqlite3_value*);
danielk19770ffba6b2004-05-24 09:10:10 +00003380
3381/*
drhd68eee02009-12-11 03:44:18 +00003382** CAPI3REF: Obtain Aggregate Function Context
drh6ed48bf2007-06-14 20:57:18 +00003383**
drhd68eee02009-12-11 03:44:18 +00003384** Implementions of aggregate SQL functions use this
3385** routine to allocate memory for storing their state.
mihailimebe796c2008-06-21 20:11:17 +00003386**
drhd68eee02009-12-11 03:44:18 +00003387** ^The first time the sqlite3_aggregate_context(C,N) routine is called
3388** for a particular aggregate function, SQLite
3389** allocates N of memory, zeroes out that memory, and returns a pointer
3390** to the new memory. ^On second and subsequent calls to
3391** sqlite3_aggregate_context() for the same aggregate function instance,
3392** the same buffer is returned. Sqlite3_aggregate_context() is normally
3393** called once for each invocation of the xStep callback and then one
3394** last time when the xFinal callback is invoked. ^(When no rows match
3395** an aggregate query, the xStep() callback of the aggregate function
3396** implementation is never called and xFinal() is called exactly once.
3397** In those cases, sqlite3_aggregate_context() might be called for the
3398** first time from within xFinal().)^
danielk19770ae8b832004-05-25 12:05:56 +00003399**
drhd68eee02009-12-11 03:44:18 +00003400** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer if N is
3401** less than or equal to zero or if a memory allocate error occurs.
drh6ed48bf2007-06-14 20:57:18 +00003402**
drhd68eee02009-12-11 03:44:18 +00003403** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
3404** determined by the N parameter on first successful call. Changing the
3405** value of N in subsequent call to sqlite3_aggregate_context() within
3406** the same aggregate function instance will not resize the memory
3407** allocation.)^
3408**
3409** ^SQLite automatically frees the memory allocated by
3410** sqlite3_aggregate_context() when the aggregate query concludes.
3411**
3412** The first parameter must be a copy of the
mihailimebe796c2008-06-21 20:11:17 +00003413** [sqlite3_context | SQL function context] that is the first parameter
drhd68eee02009-12-11 03:44:18 +00003414** to the xStep or xFinal callback routine that implements the aggregate
3415** function.
drhe53831d2007-08-17 01:14:38 +00003416**
3417** This routine must be called from the same thread in which
drh605264d2007-08-21 15:13:19 +00003418** the aggregate SQL function is running.
danielk19770ae8b832004-05-25 12:05:56 +00003419*/
drh4f26d6c2004-05-26 23:25:30 +00003420void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
danielk19777e18c252004-05-25 11:47:24 +00003421
3422/*
drhd68eee02009-12-11 03:44:18 +00003423** CAPI3REF: User Data For Functions
drh6ed48bf2007-06-14 20:57:18 +00003424**
drhd68eee02009-12-11 03:44:18 +00003425** ^The sqlite3_user_data() interface returns a copy of
drhf5befa02007-12-06 02:42:07 +00003426** the pointer that was the pUserData parameter (the 5th parameter)
shane26b34032008-05-23 17:21:09 +00003427** of the [sqlite3_create_function()]
drhf5befa02007-12-06 02:42:07 +00003428** and [sqlite3_create_function16()] routines that originally
drhfa4a4b92008-03-19 21:45:51 +00003429** registered the application defined function.
3430**
drhd68eee02009-12-11 03:44:18 +00003431** This routine must be called from the same thread in which
3432** the application-defined function is running.
3433*/
3434void *sqlite3_user_data(sqlite3_context*);
3435
3436/*
3437** CAPI3REF: Database Connection For Functions
3438**
3439** ^The sqlite3_context_db_handle() interface returns a copy of
3440** the pointer to the [database connection] (the 1st parameter)
3441** of the [sqlite3_create_function()]
3442** and [sqlite3_create_function16()] routines that originally
3443** registered the application defined function.
drhfa4a4b92008-03-19 21:45:51 +00003444*/
3445sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
3446
3447/*
drhd68eee02009-12-11 03:44:18 +00003448** CAPI3REF: Function Auxiliary Data
drh6ed48bf2007-06-14 20:57:18 +00003449**
3450** The following two functions may be used by scalar SQL functions to
mihailimebe796c2008-06-21 20:11:17 +00003451** associate metadata with argument values. If the same value is passed to
drh6ed48bf2007-06-14 20:57:18 +00003452** multiple invocations of the same SQL function during query execution, under
mihailimebe796c2008-06-21 20:11:17 +00003453** some circumstances the associated metadata may be preserved. This may
danielk1977682f68b2004-06-05 10:22:17 +00003454** be used, for example, to add a regular-expression matching scalar
3455** function. The compiled version of the regular expression is stored as
mihailimebe796c2008-06-21 20:11:17 +00003456** metadata associated with the SQL value passed as the regular expression
drh6ed48bf2007-06-14 20:57:18 +00003457** pattern. The compiled regular expression can be reused on multiple
3458** invocations of the same function so that the original pattern string
3459** does not need to be recompiled on each invocation.
danielk1977682f68b2004-06-05 10:22:17 +00003460**
drhd68eee02009-12-11 03:44:18 +00003461** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
drhf5befa02007-12-06 02:42:07 +00003462** associated by the sqlite3_set_auxdata() function with the Nth argument
drhd68eee02009-12-11 03:44:18 +00003463** value to the application-defined function. ^If no metadata has been ever
mihailimebe796c2008-06-21 20:11:17 +00003464** been set for the Nth argument of the function, or if the corresponding
3465** function parameter has changed since the meta-data was set,
3466** then sqlite3_get_auxdata() returns a NULL pointer.
danielk1977682f68b2004-06-05 10:22:17 +00003467**
drhd68eee02009-12-11 03:44:18 +00003468** ^The sqlite3_set_auxdata() interface saves the metadata
mihailimebe796c2008-06-21 20:11:17 +00003469** pointed to by its 3rd parameter as the metadata for the N-th
drhafc91042008-02-21 02:09:45 +00003470** argument of the application-defined function. Subsequent
drhf5befa02007-12-06 02:42:07 +00003471** calls to sqlite3_get_auxdata() might return this data, if it has
mihailimebe796c2008-06-21 20:11:17 +00003472** not been destroyed.
drhd68eee02009-12-11 03:44:18 +00003473** ^If it is not NULL, SQLite will invoke the destructor
drhf5befa02007-12-06 02:42:07 +00003474** function given by the 4th parameter to sqlite3_set_auxdata() on
mihailimebe796c2008-06-21 20:11:17 +00003475** the metadata when the corresponding function parameter changes
drhafc91042008-02-21 02:09:45 +00003476** or when the SQL statement completes, whichever comes first.
3477**
mihailimebe796c2008-06-21 20:11:17 +00003478** SQLite is free to call the destructor and drop metadata on any
drhd68eee02009-12-11 03:44:18 +00003479** parameter of any function at any time. ^The only guarantee is that
mihailimebe796c2008-06-21 20:11:17 +00003480** the destructor will be called before the metadata is dropped.
danielk1977682f68b2004-06-05 10:22:17 +00003481**
drhd68eee02009-12-11 03:44:18 +00003482** ^(In practice, metadata is preserved between function calls for
danielk1977682f68b2004-06-05 10:22:17 +00003483** expressions that are constant at compile time. This includes literal
drhd68eee02009-12-11 03:44:18 +00003484** values and [parameters].)^
drhe53831d2007-08-17 01:14:38 +00003485**
drhb21c8cd2007-08-21 19:33:56 +00003486** These routines must be called from the same thread in which
3487** the SQL function is running.
danielk1977682f68b2004-06-05 10:22:17 +00003488*/
drhf5befa02007-12-06 02:42:07 +00003489void *sqlite3_get_auxdata(sqlite3_context*, int N);
3490void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
danielk1977682f68b2004-06-05 10:22:17 +00003491
drha2854222004-06-17 19:04:17 +00003492
3493/*
drhd68eee02009-12-11 03:44:18 +00003494** CAPI3REF: Constants Defining Special Destructor Behavior
drh6ed48bf2007-06-14 20:57:18 +00003495**
mihailimebe796c2008-06-21 20:11:17 +00003496** These are special values for the destructor that is passed in as the
drhd68eee02009-12-11 03:44:18 +00003497** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
drha2854222004-06-17 19:04:17 +00003498** argument is SQLITE_STATIC, it means that the content pointer is constant
drhd68eee02009-12-11 03:44:18 +00003499** and will never change. It does not need to be destroyed. ^The
drha2854222004-06-17 19:04:17 +00003500** SQLITE_TRANSIENT value means that the content will likely change in
3501** the near future and that SQLite should make its own private copy of
3502** the content before returning.
drh6c9121a2007-01-26 00:51:43 +00003503**
3504** The typedef is necessary to work around problems in certain
3505** C++ compilers. See ticket #2191.
drha2854222004-06-17 19:04:17 +00003506*/
drh6c9121a2007-01-26 00:51:43 +00003507typedef void (*sqlite3_destructor_type)(void*);
3508#define SQLITE_STATIC ((sqlite3_destructor_type)0)
3509#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
danielk1977d8123362004-06-12 09:25:12 +00003510
danielk1977682f68b2004-06-05 10:22:17 +00003511/*
drhd68eee02009-12-11 03:44:18 +00003512** CAPI3REF: Setting The Result Of An SQL Function
drh6ed48bf2007-06-14 20:57:18 +00003513**
3514** These routines are used by the xFunc or xFinal callbacks that
3515** implement SQL functions and aggregates. See
3516** [sqlite3_create_function()] and [sqlite3_create_function16()]
3517** for additional information.
3518**
mihailimebe796c2008-06-21 20:11:17 +00003519** These functions work very much like the [parameter binding] family of
3520** functions used to bind values to host parameters in prepared statements.
3521** Refer to the [SQL parameter] documentation for additional information.
drh6ed48bf2007-06-14 20:57:18 +00003522**
drhd68eee02009-12-11 03:44:18 +00003523** ^The sqlite3_result_blob() interface sets the result from
mihailimebe796c2008-06-21 20:11:17 +00003524** an application-defined function to be the BLOB whose content is pointed
drhf5befa02007-12-06 02:42:07 +00003525** to by the second parameter and which is N bytes long where N is the
mihailimebe796c2008-06-21 20:11:17 +00003526** third parameter.
3527**
drhd68eee02009-12-11 03:44:18 +00003528** ^The sqlite3_result_zeroblob() interfaces set the result of
mihailimebe796c2008-06-21 20:11:17 +00003529** the application-defined function to be a BLOB containing all zero
drhf5befa02007-12-06 02:42:07 +00003530** bytes and N bytes in size, where N is the value of the 2nd parameter.
drh6ed48bf2007-06-14 20:57:18 +00003531**
drhd68eee02009-12-11 03:44:18 +00003532** ^The sqlite3_result_double() interface sets the result from
mihailimebe796c2008-06-21 20:11:17 +00003533** an application-defined function to be a floating point value specified
drhf5befa02007-12-06 02:42:07 +00003534** by its 2nd argument.
drhe53831d2007-08-17 01:14:38 +00003535**
drhd68eee02009-12-11 03:44:18 +00003536** ^The sqlite3_result_error() and sqlite3_result_error16() functions
drhf5befa02007-12-06 02:42:07 +00003537** cause the implemented SQL function to throw an exception.
drhd68eee02009-12-11 03:44:18 +00003538** ^SQLite uses the string pointed to by the
drhf5befa02007-12-06 02:42:07 +00003539** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
drhd68eee02009-12-11 03:44:18 +00003540** as the text of an error message. ^SQLite interprets the error
3541** message string from sqlite3_result_error() as UTF-8. ^SQLite
mihailimebe796c2008-06-21 20:11:17 +00003542** interprets the string from sqlite3_result_error16() as UTF-16 in native
drhd68eee02009-12-11 03:44:18 +00003543** byte order. ^If the third parameter to sqlite3_result_error()
drhf5befa02007-12-06 02:42:07 +00003544** or sqlite3_result_error16() is negative then SQLite takes as the error
3545** message all text up through the first zero character.
drhd68eee02009-12-11 03:44:18 +00003546** ^If the third parameter to sqlite3_result_error() or
drhf5befa02007-12-06 02:42:07 +00003547** sqlite3_result_error16() is non-negative then SQLite takes that many
3548** bytes (not characters) from the 2nd parameter as the error message.
drhd68eee02009-12-11 03:44:18 +00003549** ^The sqlite3_result_error() and sqlite3_result_error16()
mihailimebe796c2008-06-21 20:11:17 +00003550** routines make a private copy of the error message text before
drhafc91042008-02-21 02:09:45 +00003551** they return. Hence, the calling function can deallocate or
drhf5befa02007-12-06 02:42:07 +00003552** modify the text after they return without harm.
drhd68eee02009-12-11 03:44:18 +00003553** ^The sqlite3_result_error_code() function changes the error code
3554** returned by SQLite as a result of an error in a function. ^By default,
3555** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
drh00e087b2008-04-10 17:14:07 +00003556** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
drhf5befa02007-12-06 02:42:07 +00003557**
drhd68eee02009-12-11 03:44:18 +00003558** ^The sqlite3_result_toobig() interface causes SQLite to throw an error
drhdf6473a2009-12-13 22:20:08 +00003559** indicating that a string or BLOB is too long to represent.
mihailimebe796c2008-06-21 20:11:17 +00003560**
drhd68eee02009-12-11 03:44:18 +00003561** ^The sqlite3_result_nomem() interface causes SQLite to throw an error
mihailimebe796c2008-06-21 20:11:17 +00003562** indicating that a memory allocation failed.
drhf5befa02007-12-06 02:42:07 +00003563**
drhd68eee02009-12-11 03:44:18 +00003564** ^The sqlite3_result_int() interface sets the return value
drhf5befa02007-12-06 02:42:07 +00003565** of the application-defined function to be the 32-bit signed integer
3566** value given in the 2nd argument.
drhd68eee02009-12-11 03:44:18 +00003567** ^The sqlite3_result_int64() interface sets the return value
drhf5befa02007-12-06 02:42:07 +00003568** of the application-defined function to be the 64-bit signed integer
3569** value given in the 2nd argument.
3570**
drhd68eee02009-12-11 03:44:18 +00003571** ^The sqlite3_result_null() interface sets the return value
drhf5befa02007-12-06 02:42:07 +00003572** of the application-defined function to be NULL.
3573**
drhd68eee02009-12-11 03:44:18 +00003574** ^The sqlite3_result_text(), sqlite3_result_text16(),
drhf5befa02007-12-06 02:42:07 +00003575** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
3576** set the return value of the application-defined function to be
3577** a text string which is represented as UTF-8, UTF-16 native byte order,
3578** UTF-16 little endian, or UTF-16 big endian, respectively.
drhd68eee02009-12-11 03:44:18 +00003579** ^SQLite takes the text result from the application from
drhf5befa02007-12-06 02:42:07 +00003580** the 2nd parameter of the sqlite3_result_text* interfaces.
drhd68eee02009-12-11 03:44:18 +00003581** ^If the 3rd parameter to the sqlite3_result_text* interfaces
mihailimebe796c2008-06-21 20:11:17 +00003582** is negative, then SQLite takes result text from the 2nd parameter
drhf5befa02007-12-06 02:42:07 +00003583** through the first zero character.
drhd68eee02009-12-11 03:44:18 +00003584** ^If the 3rd parameter to the sqlite3_result_text* interfaces
drhf5befa02007-12-06 02:42:07 +00003585** is non-negative, then as many bytes (not characters) of the text
3586** pointed to by the 2nd parameter are taken as the application-defined
3587** function result.
drhd68eee02009-12-11 03:44:18 +00003588** ^If the 4th parameter to the sqlite3_result_text* interfaces
drhf5befa02007-12-06 02:42:07 +00003589** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
mihailimebe796c2008-06-21 20:11:17 +00003590** function as the destructor on the text or BLOB result when it has
drhf5befa02007-12-06 02:42:07 +00003591** finished using that result.
drhd68eee02009-12-11 03:44:18 +00003592** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
mihailimebe796c2008-06-21 20:11:17 +00003593** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
3594** assumes that the text or BLOB result is in constant space and does not
drh9e42f8a2009-08-13 20:15:29 +00003595** copy the content of the parameter nor call a destructor on the content
3596** when it has finished using that result.
drhd68eee02009-12-11 03:44:18 +00003597** ^If the 4th parameter to the sqlite3_result_text* interfaces
drhf5befa02007-12-06 02:42:07 +00003598** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
3599** then SQLite makes a copy of the result into space obtained from
3600** from [sqlite3_malloc()] before it returns.
3601**
drhd68eee02009-12-11 03:44:18 +00003602** ^The sqlite3_result_value() interface sets the result of
drhaa28e142008-03-18 13:47:20 +00003603** the application-defined function to be a copy the
drhd68eee02009-12-11 03:44:18 +00003604** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
drhf5befa02007-12-06 02:42:07 +00003605** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
mihailimebe796c2008-06-21 20:11:17 +00003606** so that the [sqlite3_value] specified in the parameter may change or
drhf5befa02007-12-06 02:42:07 +00003607** be deallocated after sqlite3_result_value() returns without harm.
drhd68eee02009-12-11 03:44:18 +00003608** ^A [protected sqlite3_value] object may always be used where an
drhaa28e142008-03-18 13:47:20 +00003609** [unprotected sqlite3_value] object is required, so either
3610** kind of [sqlite3_value] object can be used with this interface.
drhf5befa02007-12-06 02:42:07 +00003611**
mihailimebe796c2008-06-21 20:11:17 +00003612** If these routines are called from within the different thread
shane26b34032008-05-23 17:21:09 +00003613** than the one containing the application-defined function that received
drhf5befa02007-12-06 02:42:07 +00003614** the [sqlite3_context] pointer, the results are undefined.
danielk19777e18c252004-05-25 11:47:24 +00003615*/
danielk1977d8123362004-06-12 09:25:12 +00003616void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
drh4f26d6c2004-05-26 23:25:30 +00003617void sqlite3_result_double(sqlite3_context*, double);
danielk19777e18c252004-05-25 11:47:24 +00003618void sqlite3_result_error(sqlite3_context*, const char*, int);
3619void sqlite3_result_error16(sqlite3_context*, const void*, int);
drh6ed48bf2007-06-14 20:57:18 +00003620void sqlite3_result_error_toobig(sqlite3_context*);
danielk1977a1644fd2007-08-29 12:31:25 +00003621void sqlite3_result_error_nomem(sqlite3_context*);
drh69544ec2008-02-06 14:11:34 +00003622void sqlite3_result_error_code(sqlite3_context*, int);
drh4f26d6c2004-05-26 23:25:30 +00003623void sqlite3_result_int(sqlite3_context*, int);
drh6d2069d2007-08-14 01:58:53 +00003624void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
drh4f26d6c2004-05-26 23:25:30 +00003625void sqlite3_result_null(sqlite3_context*);
danielk1977d8123362004-06-12 09:25:12 +00003626void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
3627void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
3628void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
3629void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
drh4f26d6c2004-05-26 23:25:30 +00003630void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
drhb026e052007-05-02 01:34:31 +00003631void sqlite3_result_zeroblob(sqlite3_context*, int n);
drhf9b596e2004-05-26 16:54:42 +00003632
drh52619df2004-06-11 17:48:02 +00003633/*
drhd68eee02009-12-11 03:44:18 +00003634** CAPI3REF: Define New Collating Sequences
drh6ed48bf2007-06-14 20:57:18 +00003635**
3636** These functions are used to add new collation sequences to the
mihailimebe796c2008-06-21 20:11:17 +00003637** [database connection] specified as the first argument.
danielk19777cedc8d2004-06-10 10:50:08 +00003638**
drhd68eee02009-12-11 03:44:18 +00003639** ^The name of the new collation sequence is specified as a UTF-8 string
drh6ed48bf2007-06-14 20:57:18 +00003640** for sqlite3_create_collation() and sqlite3_create_collation_v2()
drhd68eee02009-12-11 03:44:18 +00003641** and a UTF-16 string for sqlite3_create_collation16(). ^In all cases
drh6ed48bf2007-06-14 20:57:18 +00003642** the name is passed as the second function argument.
danielk19777cedc8d2004-06-10 10:50:08 +00003643**
drhd68eee02009-12-11 03:44:18 +00003644** ^The third argument may be one of the constants [SQLITE_UTF8],
drh51c7d862009-04-27 18:46:06 +00003645** [SQLITE_UTF16LE], or [SQLITE_UTF16BE], indicating that the user-supplied
danielk19777cedc8d2004-06-10 10:50:08 +00003646** routine expects to be passed pointers to strings encoded using UTF-8,
drhd68eee02009-12-11 03:44:18 +00003647** UTF-16 little-endian, or UTF-16 big-endian, respectively. ^The
drh51c7d862009-04-27 18:46:06 +00003648** third argument might also be [SQLITE_UTF16] to indicate that the routine
3649** expects pointers to be UTF-16 strings in the native byte order, or the
3650** argument can be [SQLITE_UTF16_ALIGNED] if the
drh4145f832007-10-12 18:30:12 +00003651** the routine expects pointers to 16-bit word aligned strings
drh51c7d862009-04-27 18:46:06 +00003652** of UTF-16 in the native byte order.
danielk19777cedc8d2004-06-10 10:50:08 +00003653**
3654** A pointer to the user supplied routine must be passed as the fifth
drhd68eee02009-12-11 03:44:18 +00003655** argument. ^If it is NULL, this is the same as deleting the collation
drhf5befa02007-12-06 02:42:07 +00003656** sequence (so that SQLite cannot call it anymore).
drhd68eee02009-12-11 03:44:18 +00003657** ^Each time the application supplied function is invoked, it is passed
mihailimebe796c2008-06-21 20:11:17 +00003658** as its first parameter a copy of the void* passed as the fourth argument
3659** to sqlite3_create_collation() or sqlite3_create_collation16().
danielk19777cedc8d2004-06-10 10:50:08 +00003660**
drhd68eee02009-12-11 03:44:18 +00003661** ^The remaining arguments to the application-supplied routine are two strings,
drh33c1be32008-01-30 16:16:14 +00003662** each represented by a (length, data) pair and encoded in the encoding
danielk19777cedc8d2004-06-10 10:50:08 +00003663** that was passed as the third argument when the collation sequence was
drhfb434032009-12-11 23:11:26 +00003664** registered. The application defined collation routine should
mihailimebe796c2008-06-21 20:11:17 +00003665** return negative, zero or positive if the first string is less than,
3666** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
drh6ed48bf2007-06-14 20:57:18 +00003667**
drhd68eee02009-12-11 03:44:18 +00003668** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
shane26b34032008-05-23 17:21:09 +00003669** except that it takes an extra argument which is a destructor for
drhd68eee02009-12-11 03:44:18 +00003670** the collation. ^The destructor is called when the collation is
drh6ed48bf2007-06-14 20:57:18 +00003671** destroyed and is passed a copy of the fourth parameter void* pointer
drhf5befa02007-12-06 02:42:07 +00003672** of the sqlite3_create_collation_v2().
drhd68eee02009-12-11 03:44:18 +00003673** ^Collations are destroyed when they are overridden by later calls to the
mihailimebe796c2008-06-21 20:11:17 +00003674** collation creation functions or when the [database connection] is closed
3675** using [sqlite3_close()].
drhafc91042008-02-21 02:09:45 +00003676**
drh51c7d862009-04-27 18:46:06 +00003677** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
danielk19777cedc8d2004-06-10 10:50:08 +00003678*/
danielk19770202b292004-06-09 09:55:16 +00003679int sqlite3_create_collation(
3680 sqlite3*,
3681 const char *zName,
danielk19777cedc8d2004-06-10 10:50:08 +00003682 int eTextRep,
danielk19770202b292004-06-09 09:55:16 +00003683 void*,
3684 int(*xCompare)(void*,int,const void*,int,const void*)
3685);
drh6ed48bf2007-06-14 20:57:18 +00003686int sqlite3_create_collation_v2(
3687 sqlite3*,
3688 const char *zName,
3689 int eTextRep,
3690 void*,
3691 int(*xCompare)(void*,int,const void*,int,const void*),
3692 void(*xDestroy)(void*)
3693);
danielk19770202b292004-06-09 09:55:16 +00003694int sqlite3_create_collation16(
3695 sqlite3*,
mihailimbda2e622008-06-23 11:23:14 +00003696 const void *zName,
danielk19777cedc8d2004-06-10 10:50:08 +00003697 int eTextRep,
danielk19770202b292004-06-09 09:55:16 +00003698 void*,
3699 int(*xCompare)(void*,int,const void*,int,const void*)
3700);
3701
danielk19777cedc8d2004-06-10 10:50:08 +00003702/*
drhfb434032009-12-11 23:11:26 +00003703** CAPI3REF: Collation Needed Callbacks
danielk1977a393c032007-05-07 14:58:53 +00003704**
drhd68eee02009-12-11 03:44:18 +00003705** ^To avoid having to register all collation sequences before a database
danielk19777cedc8d2004-06-10 10:50:08 +00003706** can be used, a single callback function may be registered with the
drh9be37f62009-12-12 23:57:36 +00003707** [database connection] to be invoked whenever an undefined collation
mihailimdc884822008-06-22 08:58:50 +00003708** sequence is required.
danielk19777cedc8d2004-06-10 10:50:08 +00003709**
drhd68eee02009-12-11 03:44:18 +00003710** ^If the function is registered using the sqlite3_collation_needed() API,
danielk19777cedc8d2004-06-10 10:50:08 +00003711** then it is passed the names of undefined collation sequences as strings
drhd68eee02009-12-11 03:44:18 +00003712** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
mihailimdc884822008-06-22 08:58:50 +00003713** the names are passed as UTF-16 in machine native byte order.
drh9be37f62009-12-12 23:57:36 +00003714** ^A call to either function replaces the existing collation-needed callback.
danielk19777cedc8d2004-06-10 10:50:08 +00003715**
drhd68eee02009-12-11 03:44:18 +00003716** ^(When the callback is invoked, the first argument passed is a copy
danielk19777cedc8d2004-06-10 10:50:08 +00003717** of the second argument to sqlite3_collation_needed() or
drhafc91042008-02-21 02:09:45 +00003718** sqlite3_collation_needed16(). The second argument is the database
mihailimdc884822008-06-22 08:58:50 +00003719** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
3720** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
3721** sequence function required. The fourth parameter is the name of the
drhd68eee02009-12-11 03:44:18 +00003722** required collation sequence.)^
danielk19777cedc8d2004-06-10 10:50:08 +00003723**
drh6ed48bf2007-06-14 20:57:18 +00003724** The callback function should register the desired collation using
3725** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
3726** [sqlite3_create_collation_v2()].
danielk19777cedc8d2004-06-10 10:50:08 +00003727*/
3728int sqlite3_collation_needed(
3729 sqlite3*,
3730 void*,
3731 void(*)(void*,sqlite3*,int eTextRep,const char*)
3732);
3733int sqlite3_collation_needed16(
3734 sqlite3*,
3735 void*,
3736 void(*)(void*,sqlite3*,int eTextRep,const void*)
3737);
3738
drhd4542142010-03-30 11:57:01 +00003739#ifdef SQLITE_HAS_CODEC
drh2011d5f2004-07-22 02:40:37 +00003740/*
3741** Specify the key for an encrypted database. This routine should be
3742** called right after sqlite3_open().
3743**
3744** The code to implement this API is not available in the public release
3745** of SQLite.
3746*/
3747int sqlite3_key(
3748 sqlite3 *db, /* Database to be rekeyed */
3749 const void *pKey, int nKey /* The key */
3750);
3751
3752/*
3753** Change the key on an open database. If the current database is not
3754** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
3755** database is decrypted.
3756**
3757** The code to implement this API is not available in the public release
3758** of SQLite.
3759*/
3760int sqlite3_rekey(
3761 sqlite3 *db, /* Database to be rekeyed */
3762 const void *pKey, int nKey /* The new key */
3763);
danielk19770202b292004-06-09 09:55:16 +00003764
drhab3f9fe2004-08-14 17:10:10 +00003765/*
shaneh959dda62010-01-28 19:56:27 +00003766** Specify the activation key for a SEE database. Unless
3767** activated, none of the SEE routines will work.
3768*/
drha7564662010-02-22 19:32:31 +00003769void sqlite3_activate_see(
3770 const char *zPassPhrase /* Activation phrase */
3771);
3772#endif
3773
3774#ifdef SQLITE_ENABLE_CEROD
shaneh959dda62010-01-28 19:56:27 +00003775/*
3776** Specify the activation key for a CEROD database. Unless
3777** activated, none of the CEROD routines will work.
3778*/
drha7564662010-02-22 19:32:31 +00003779void sqlite3_activate_cerod(
3780 const char *zPassPhrase /* Activation phrase */
3781);
shaneh959dda62010-01-28 19:56:27 +00003782#endif
3783
3784/*
drhd68eee02009-12-11 03:44:18 +00003785** CAPI3REF: Suspend Execution For A Short Time
drh6ed48bf2007-06-14 20:57:18 +00003786**
drhd68eee02009-12-11 03:44:18 +00003787** ^The sqlite3_sleep() function causes the current thread to suspend execution
drhfddfa2d2007-12-05 18:05:16 +00003788** for at least a number of milliseconds specified in its parameter.
danielk1977600dd0b2005-01-20 01:14:23 +00003789**
drhd68eee02009-12-11 03:44:18 +00003790** ^If the operating system does not support sleep requests with
mihailimdc884822008-06-22 08:58:50 +00003791** millisecond time resolution, then the time will be rounded up to
drhd68eee02009-12-11 03:44:18 +00003792** the nearest second. ^The number of milliseconds of sleep actually
danielk1977600dd0b2005-01-20 01:14:23 +00003793** requested from the operating system is returned.
drh8bacf972007-08-25 16:21:29 +00003794**
drhd68eee02009-12-11 03:44:18 +00003795** ^SQLite implements this interface by calling the xSleep()
drhafc91042008-02-21 02:09:45 +00003796** method of the default [sqlite3_vfs] object.
danielk1977600dd0b2005-01-20 01:14:23 +00003797*/
3798int sqlite3_sleep(int);
3799
3800/*
drhd68eee02009-12-11 03:44:18 +00003801** CAPI3REF: Name Of The Folder Holding Temporary Files
drhd89bd002005-01-22 03:03:54 +00003802**
drh7a98b852009-12-13 23:03:01 +00003803** ^(If this global variable is made to point to a string which is
shane26b34032008-05-23 17:21:09 +00003804** the name of a folder (a.k.a. directory), then all temporary files
drhd68eee02009-12-11 03:44:18 +00003805** created by SQLite when using a built-in [sqlite3_vfs | VFS]
drh7a98b852009-12-13 23:03:01 +00003806** will be placed in that directory.)^ ^If this variable
mihailimdc884822008-06-22 08:58:50 +00003807** is a NULL pointer, then SQLite performs a search for an appropriate
3808** temporary file directory.
drhab3f9fe2004-08-14 17:10:10 +00003809**
drh1a25f112009-04-06 15:55:03 +00003810** It is not safe to read or modify this variable in more than one
3811** thread at a time. It is not safe to read or modify this variable
3812** if a [database connection] is being used at the same time in a separate
3813** thread.
3814** It is intended that this variable be set once
drh4ff7fa02007-09-01 18:17:21 +00003815** as part of process initialization and before any SQLite interface
drh1a25f112009-04-06 15:55:03 +00003816** routines have been called and that this variable remain unchanged
3817** thereafter.
3818**
drhd68eee02009-12-11 03:44:18 +00003819** ^The [temp_store_directory pragma] may modify this variable and cause
3820** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
drh1a25f112009-04-06 15:55:03 +00003821** the [temp_store_directory pragma] always assumes that any string
3822** that this variable points to is held in memory obtained from
3823** [sqlite3_malloc] and the pragma may attempt to free that memory
3824** using [sqlite3_free].
3825** Hence, if this variable is modified directly, either it should be
3826** made NULL or made to point to memory obtained from [sqlite3_malloc]
3827** or else the use of the [temp_store_directory pragma] should be avoided.
drhab3f9fe2004-08-14 17:10:10 +00003828*/
drh73be5012007-08-08 12:11:21 +00003829SQLITE_EXTERN char *sqlite3_temp_directory;
drhab3f9fe2004-08-14 17:10:10 +00003830
danielk19776b456a22005-03-21 04:04:02 +00003831/*
drhd68eee02009-12-11 03:44:18 +00003832** CAPI3REF: Test For Auto-Commit Mode
mihailim15194222008-06-22 09:55:14 +00003833** KEYWORDS: {autocommit mode}
danielk19776b456a22005-03-21 04:04:02 +00003834**
drhd68eee02009-12-11 03:44:18 +00003835** ^The sqlite3_get_autocommit() interface returns non-zero or
drhf5befa02007-12-06 02:42:07 +00003836** zero if the given database connection is or is not in autocommit mode,
drhd68eee02009-12-11 03:44:18 +00003837** respectively. ^Autocommit mode is on by default.
3838** ^Autocommit mode is disabled by a [BEGIN] statement.
3839** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
drhe30f4422007-08-21 16:15:55 +00003840**
drh7c3472a2007-10-03 20:15:28 +00003841** If certain kinds of errors occur on a statement within a multi-statement
mihailimdc884822008-06-22 08:58:50 +00003842** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
drh7c3472a2007-10-03 20:15:28 +00003843** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
drh33c1be32008-01-30 16:16:14 +00003844** transaction might be rolled back automatically. The only way to
mihailimdc884822008-06-22 08:58:50 +00003845** find out whether SQLite automatically rolled back the transaction after
drh33c1be32008-01-30 16:16:14 +00003846** an error is to use this function.
drh7c3472a2007-10-03 20:15:28 +00003847**
drh8b39db12009-02-18 18:37:58 +00003848** If another thread changes the autocommit status of the database
3849** connection while this routine is running, then the return value
3850** is undefined.
drh3e1d8e62005-05-26 16:23:34 +00003851*/
3852int sqlite3_get_autocommit(sqlite3*);
3853
drh51942bc2005-06-12 22:01:42 +00003854/*
drhd68eee02009-12-11 03:44:18 +00003855** CAPI3REF: Find The Database Handle Of A Prepared Statement
drh6ed48bf2007-06-14 20:57:18 +00003856**
drhd68eee02009-12-11 03:44:18 +00003857** ^The sqlite3_db_handle interface returns the [database connection] handle
3858** to which a [prepared statement] belongs. ^The [database connection]
3859** returned by sqlite3_db_handle is the same [database connection]
3860** that was the first argument
mihailimdc884822008-06-22 08:58:50 +00003861** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
3862** create the statement in the first place.
drh51942bc2005-06-12 22:01:42 +00003863*/
3864sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
drh3e1d8e62005-05-26 16:23:34 +00003865
drhbb5a9c32008-06-19 02:52:25 +00003866/*
drhd68eee02009-12-11 03:44:18 +00003867** CAPI3REF: Find the next prepared statement
drhbb5a9c32008-06-19 02:52:25 +00003868**
drhd68eee02009-12-11 03:44:18 +00003869** ^This interface returns a pointer to the next [prepared statement] after
3870** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
mihailimdc884822008-06-22 08:58:50 +00003871** then this interface returns a pointer to the first prepared statement
drhd68eee02009-12-11 03:44:18 +00003872** associated with the database connection pDb. ^If no prepared statement
mihailimdc884822008-06-22 08:58:50 +00003873** satisfies the conditions of this routine, it returns NULL.
drhbb5a9c32008-06-19 02:52:25 +00003874**
drh8b39db12009-02-18 18:37:58 +00003875** The [database connection] pointer D in a call to
3876** [sqlite3_next_stmt(D,S)] must refer to an open database
3877** connection and in particular must not be a NULL pointer.
drhbb5a9c32008-06-19 02:52:25 +00003878*/
3879sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
3880
drhb37df7b2005-10-13 02:09:49 +00003881/*
drhfb434032009-12-11 23:11:26 +00003882** CAPI3REF: Commit And Rollback Notification Callbacks
drh6ed48bf2007-06-14 20:57:18 +00003883**
drhd68eee02009-12-11 03:44:18 +00003884** ^The sqlite3_commit_hook() interface registers a callback
drhabda6112009-05-14 22:37:47 +00003885** function to be invoked whenever a transaction is [COMMIT | committed].
drhd68eee02009-12-11 03:44:18 +00003886** ^Any callback set by a previous call to sqlite3_commit_hook()
drhf5befa02007-12-06 02:42:07 +00003887** for the same database connection is overridden.
drhd68eee02009-12-11 03:44:18 +00003888** ^The sqlite3_rollback_hook() interface registers a callback
drhabda6112009-05-14 22:37:47 +00003889** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
drhd68eee02009-12-11 03:44:18 +00003890** ^Any callback set by a previous call to sqlite3_rollback_hook()
drhf5befa02007-12-06 02:42:07 +00003891** for the same database connection is overridden.
drhd68eee02009-12-11 03:44:18 +00003892** ^The pArg argument is passed through to the callback.
3893** ^If the callback on a commit hook function returns non-zero,
mihailimdc884822008-06-22 08:58:50 +00003894** then the commit is converted into a rollback.
drh6ed48bf2007-06-14 20:57:18 +00003895**
drhd68eee02009-12-11 03:44:18 +00003896** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
3897** return the P argument from the previous call of the same function
3898** on the same [database connection] D, or NULL for
3899** the first call for each function on D.
drh6ed48bf2007-06-14 20:57:18 +00003900**
drhc8075422008-09-10 13:09:23 +00003901** The callback implementation must not do anything that will modify
3902** the database connection that invoked the callback. Any actions
3903** to modify the database connection must be deferred until after the
3904** completion of the [sqlite3_step()] call that triggered the commit
3905** or rollback hook in the first place.
3906** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3907** database connections for the meaning of "modify" in this paragraph.
3908**
drhd68eee02009-12-11 03:44:18 +00003909** ^Registering a NULL function disables the callback.
drh6ed48bf2007-06-14 20:57:18 +00003910**
drhd68eee02009-12-11 03:44:18 +00003911** ^When the commit hook callback routine returns zero, the [COMMIT]
3912** operation is allowed to continue normally. ^If the commit hook
drhabda6112009-05-14 22:37:47 +00003913** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
drhd68eee02009-12-11 03:44:18 +00003914** ^The rollback hook is invoked on a rollback that results from a commit
drhabda6112009-05-14 22:37:47 +00003915** hook returning non-zero, just as it would be with any other rollback.
3916**
drhd68eee02009-12-11 03:44:18 +00003917** ^For the purposes of this API, a transaction is said to have been
drh6ed48bf2007-06-14 20:57:18 +00003918** rolled back if an explicit "ROLLBACK" statement is executed, or
drhf5befa02007-12-06 02:42:07 +00003919** an error or constraint causes an implicit rollback to occur.
drhd68eee02009-12-11 03:44:18 +00003920** ^The rollback callback is not invoked if a transaction is
drhf5befa02007-12-06 02:42:07 +00003921** automatically rolled back because the database connection is closed.
drh6ed48bf2007-06-14 20:57:18 +00003922**
drhabda6112009-05-14 22:37:47 +00003923** See also the [sqlite3_update_hook()] interface.
drh6ed48bf2007-06-14 20:57:18 +00003924*/
3925void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
3926void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
3927
3928/*
drhd68eee02009-12-11 03:44:18 +00003929** CAPI3REF: Data Change Notification Callbacks
drh6ed48bf2007-06-14 20:57:18 +00003930**
drhd68eee02009-12-11 03:44:18 +00003931** ^The sqlite3_update_hook() interface registers a callback function
mihailimdc884822008-06-22 08:58:50 +00003932** with the [database connection] identified by the first argument
3933** to be invoked whenever a row is updated, inserted or deleted.
drhd68eee02009-12-11 03:44:18 +00003934** ^Any callback set by a previous call to this function
mihailimdc884822008-06-22 08:58:50 +00003935** for the same database connection is overridden.
danielk197794eb6a12005-12-15 15:22:08 +00003936**
drhd68eee02009-12-11 03:44:18 +00003937** ^The second argument is a pointer to the function to invoke when a
mihailimdc884822008-06-22 08:58:50 +00003938** row is updated, inserted or deleted.
drhd68eee02009-12-11 03:44:18 +00003939** ^The first argument to the callback is a copy of the third argument
mihailimdc884822008-06-22 08:58:50 +00003940** to sqlite3_update_hook().
drhd68eee02009-12-11 03:44:18 +00003941** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
mihailimdc884822008-06-22 08:58:50 +00003942** or [SQLITE_UPDATE], depending on the operation that caused the callback
3943** to be invoked.
drhd68eee02009-12-11 03:44:18 +00003944** ^The third and fourth arguments to the callback contain pointers to the
mihailimdc884822008-06-22 08:58:50 +00003945** database and table name containing the affected row.
drhd68eee02009-12-11 03:44:18 +00003946** ^The final callback parameter is the [rowid] of the row.
3947** ^In the case of an update, this is the [rowid] after the update takes place.
danielk197794eb6a12005-12-15 15:22:08 +00003948**
drhd68eee02009-12-11 03:44:18 +00003949** ^(The update hook is not invoked when internal system tables are
3950** modified (i.e. sqlite_master and sqlite_sequence).)^
danielk197771fd80b2005-12-16 06:54:01 +00003951**
drhd68eee02009-12-11 03:44:18 +00003952** ^In the current implementation, the update hook
drhabda6112009-05-14 22:37:47 +00003953** is not invoked when duplication rows are deleted because of an
drhd68eee02009-12-11 03:44:18 +00003954** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
drhabda6112009-05-14 22:37:47 +00003955** invoked when rows are deleted using the [truncate optimization].
3956** The exceptions defined in this paragraph might change in a future
3957** release of SQLite.
3958**
drhc8075422008-09-10 13:09:23 +00003959** The update hook implementation must not do anything that will modify
3960** the database connection that invoked the update hook. Any actions
3961** to modify the database connection must be deferred until after the
3962** completion of the [sqlite3_step()] call that triggered the update hook.
3963** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3964** database connections for the meaning of "modify" in this paragraph.
3965**
drhd68eee02009-12-11 03:44:18 +00003966** ^The sqlite3_update_hook(D,C,P) function
3967** returns the P argument from the previous call
3968** on the same [database connection] D, or NULL for
3969** the first call on D.
drhafc91042008-02-21 02:09:45 +00003970**
drhabda6112009-05-14 22:37:47 +00003971** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
3972** interfaces.
danielk197794eb6a12005-12-15 15:22:08 +00003973*/
danielk197771fd80b2005-12-16 06:54:01 +00003974void *sqlite3_update_hook(
danielk197794eb6a12005-12-15 15:22:08 +00003975 sqlite3*,
drh6d2069d2007-08-14 01:58:53 +00003976 void(*)(void *,int ,char const *,char const *,sqlite3_int64),
danielk197794eb6a12005-12-15 15:22:08 +00003977 void*
3978);
danielk197713a68c32005-12-15 10:11:30 +00003979
danielk1977f3f06bb2005-12-16 15:24:28 +00003980/*
drhd68eee02009-12-11 03:44:18 +00003981** CAPI3REF: Enable Or Disable Shared Pager Cache
drhe33b0ed2009-08-06 17:40:45 +00003982** KEYWORDS: {shared cache}
danielk1977f3f06bb2005-12-16 15:24:28 +00003983**
drhd68eee02009-12-11 03:44:18 +00003984** ^(This routine enables or disables the sharing of the database cache
mihailimdc884822008-06-22 08:58:50 +00003985** and schema data structures between [database connection | connections]
3986** to the same database. Sharing is enabled if the argument is true
drhd68eee02009-12-11 03:44:18 +00003987** and disabled if the argument is false.)^
danielk1977f3f06bb2005-12-16 15:24:28 +00003988**
drhd68eee02009-12-11 03:44:18 +00003989** ^Cache sharing is enabled and disabled for an entire process.
mihailimdc884822008-06-22 08:58:50 +00003990** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
3991** sharing was enabled or disabled for each thread separately.
drh6ed48bf2007-06-14 20:57:18 +00003992**
drhd68eee02009-12-11 03:44:18 +00003993** ^(The cache sharing mode set by this interface effects all subsequent
drhe30f4422007-08-21 16:15:55 +00003994** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
drhafc91042008-02-21 02:09:45 +00003995** Existing database connections continue use the sharing mode
drhd68eee02009-12-11 03:44:18 +00003996** that was in effect at the time they were opened.)^
drh6ed48bf2007-06-14 20:57:18 +00003997**
drhd68eee02009-12-11 03:44:18 +00003998** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
3999** successfully. An [error code] is returned otherwise.)^
drh6ed48bf2007-06-14 20:57:18 +00004000**
drhd68eee02009-12-11 03:44:18 +00004001** ^Shared cache is disabled by default. But this might change in
drh4ff7fa02007-09-01 18:17:21 +00004002** future releases of SQLite. Applications that care about shared
4003** cache setting should set it explicitly.
drhafc91042008-02-21 02:09:45 +00004004**
drhaff46972009-02-12 17:07:34 +00004005** See Also: [SQLite Shared-Cache Mode]
danielk1977aef0bf62005-12-30 16:28:01 +00004006*/
4007int sqlite3_enable_shared_cache(int);
4008
4009/*
drhd68eee02009-12-11 03:44:18 +00004010** CAPI3REF: Attempt To Free Heap Memory
drh6ed48bf2007-06-14 20:57:18 +00004011**
drhd68eee02009-12-11 03:44:18 +00004012** ^The sqlite3_release_memory() interface attempts to free N bytes
mihailim04bcc002008-06-22 10:21:27 +00004013** of heap memory by deallocating non-essential memory allocations
drhd68eee02009-12-11 03:44:18 +00004014** held by the database library. Memory used to cache database
mihailim04bcc002008-06-22 10:21:27 +00004015** pages to improve performance is an example of non-essential memory.
drhd68eee02009-12-11 03:44:18 +00004016** ^sqlite3_release_memory() returns the number of bytes actually freed,
mihailim04bcc002008-06-22 10:21:27 +00004017** which might be more or less than the amount requested.
danielk197752622822006-01-09 09:59:49 +00004018*/
4019int sqlite3_release_memory(int);
4020
4021/*
drhd68eee02009-12-11 03:44:18 +00004022** CAPI3REF: Impose A Limit On Heap Size
drh6ed48bf2007-06-14 20:57:18 +00004023**
drhd68eee02009-12-11 03:44:18 +00004024** ^The sqlite3_soft_heap_limit() interface places a "soft" limit
mihailimdc884822008-06-22 08:58:50 +00004025** on the amount of heap memory that may be allocated by SQLite.
drhd68eee02009-12-11 03:44:18 +00004026** ^If an internal allocation is requested that would exceed the
mihailimdc884822008-06-22 08:58:50 +00004027** soft heap limit, [sqlite3_release_memory()] is invoked one or
4028** more times to free up some space before the allocation is performed.
danielk197752622822006-01-09 09:59:49 +00004029**
drhdf6473a2009-12-13 22:20:08 +00004030** ^The limit is called "soft" because if [sqlite3_release_memory()]
mihailimdc884822008-06-22 08:58:50 +00004031** cannot free sufficient memory to prevent the limit from being exceeded,
drhe30f4422007-08-21 16:15:55 +00004032** the memory is allocated anyway and the current operation proceeds.
drh6ed48bf2007-06-14 20:57:18 +00004033**
drhd68eee02009-12-11 03:44:18 +00004034** ^A negative or zero value for N means that there is no soft heap limit and
drhe30f4422007-08-21 16:15:55 +00004035** [sqlite3_release_memory()] will only be called when memory is exhausted.
drhd68eee02009-12-11 03:44:18 +00004036** ^The default value for the soft heap limit is zero.
drh6ed48bf2007-06-14 20:57:18 +00004037**
drhd68eee02009-12-11 03:44:18 +00004038** ^(SQLite makes a best effort to honor the soft heap limit.
shane26b34032008-05-23 17:21:09 +00004039** But if the soft heap limit cannot be honored, execution will
drhd68eee02009-12-11 03:44:18 +00004040** continue without error or notification.)^ This is why the limit is
drh6ed48bf2007-06-14 20:57:18 +00004041** called a "soft" limit. It is advisory only.
4042**
drhe30f4422007-08-21 16:15:55 +00004043** Prior to SQLite version 3.5.0, this routine only constrained the memory
4044** allocated by a single thread - the same thread in which this routine
4045** runs. Beginning with SQLite version 3.5.0, the soft heap limit is
drhafc91042008-02-21 02:09:45 +00004046** applied to all threads. The value specified for the soft heap limit
4047** is an upper bound on the total memory allocation for all threads. In
drh8bacf972007-08-25 16:21:29 +00004048** version 3.5.0 there is no mechanism for limiting the heap usage for
4049** individual threads.
danielk197752622822006-01-09 09:59:49 +00004050*/
drhd2d4a6b2006-01-10 15:18:27 +00004051void sqlite3_soft_heap_limit(int);
danielk197752622822006-01-09 09:59:49 +00004052
4053/*
drhfb434032009-12-11 23:11:26 +00004054** CAPI3REF: Extract Metadata About A Column Of A Table
drh6ed48bf2007-06-14 20:57:18 +00004055**
drhd68eee02009-12-11 03:44:18 +00004056** ^This routine returns metadata about a specific column of a specific
mihailimdc884822008-06-22 08:58:50 +00004057** database table accessible using the [database connection] handle
4058** passed as the first function argument.
danielk1977deb802c2006-02-09 13:43:28 +00004059**
drhd68eee02009-12-11 03:44:18 +00004060** ^The column is identified by the second, third and fourth parameters to
drhdf6473a2009-12-13 22:20:08 +00004061** this function. ^The second parameter is either the name of the database
4062** (i.e. "main", "temp", or an attached database) containing the specified
4063** table or NULL. ^If it is NULL, then all attached databases are searched
mihailimdc884822008-06-22 08:58:50 +00004064** for the table using the same algorithm used by the database engine to
drh7a98b852009-12-13 23:03:01 +00004065** resolve unqualified table references.
danielk1977deb802c2006-02-09 13:43:28 +00004066**
drhd68eee02009-12-11 03:44:18 +00004067** ^The third and fourth parameters to this function are the table and column
mihailimdc884822008-06-22 08:58:50 +00004068** name of the desired column, respectively. Neither of these parameters
danielk1977deb802c2006-02-09 13:43:28 +00004069** may be NULL.
4070**
drhd68eee02009-12-11 03:44:18 +00004071** ^Metadata is returned by writing to the memory locations passed as the 5th
4072** and subsequent parameters to this function. ^Any of these arguments may be
mihailimdc884822008-06-22 08:58:50 +00004073** NULL, in which case the corresponding element of metadata is omitted.
mihailim15194222008-06-22 09:55:14 +00004074**
drhd68eee02009-12-11 03:44:18 +00004075** ^(<blockquote>
mihailimdc884822008-06-22 08:58:50 +00004076** <table border="1">
4077** <tr><th> Parameter <th> Output<br>Type <th> Description
danielk1977deb802c2006-02-09 13:43:28 +00004078**
mihailimdc884822008-06-22 08:58:50 +00004079** <tr><td> 5th <td> const char* <td> Data type
4080** <tr><td> 6th <td> const char* <td> Name of default collation sequence
4081** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
4082** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
drh49c3d572008-12-15 22:51:38 +00004083** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
mihailimdc884822008-06-22 08:58:50 +00004084** </table>
drhd68eee02009-12-11 03:44:18 +00004085** </blockquote>)^
danielk1977deb802c2006-02-09 13:43:28 +00004086**
drhd68eee02009-12-11 03:44:18 +00004087** ^The memory pointed to by the character pointers returned for the
mihailimdc884822008-06-22 08:58:50 +00004088** declaration type and collation sequence is valid only until the next
4089** call to any SQLite API function.
danielk1977deb802c2006-02-09 13:43:28 +00004090**
drhd68eee02009-12-11 03:44:18 +00004091** ^If the specified table is actually a view, an [error code] is returned.
danielk1977deb802c2006-02-09 13:43:28 +00004092**
drhd68eee02009-12-11 03:44:18 +00004093** ^If the specified column is "rowid", "oid" or "_rowid_" and an
drh49c3d572008-12-15 22:51:38 +00004094** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
drhd68eee02009-12-11 03:44:18 +00004095** parameters are set for the explicitly declared column. ^(If there is no
drh49c3d572008-12-15 22:51:38 +00004096** explicitly declared [INTEGER PRIMARY KEY] column, then the output
mihailimdc884822008-06-22 08:58:50 +00004097** parameters are set as follows:
danielk1977deb802c2006-02-09 13:43:28 +00004098**
drh6ed48bf2007-06-14 20:57:18 +00004099** <pre>
danielk1977deb802c2006-02-09 13:43:28 +00004100** data type: "INTEGER"
4101** collation sequence: "BINARY"
4102** not null: 0
4103** primary key: 1
4104** auto increment: 0
drhd68eee02009-12-11 03:44:18 +00004105** </pre>)^
danielk1977deb802c2006-02-09 13:43:28 +00004106**
drhd68eee02009-12-11 03:44:18 +00004107** ^(This function may load one or more schemas from database files. If an
danielk1977deb802c2006-02-09 13:43:28 +00004108** error occurs during this process, or if the requested table or column
mihailimdc884822008-06-22 08:58:50 +00004109** cannot be found, an [error code] is returned and an error message left
drhd68eee02009-12-11 03:44:18 +00004110** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^
danielk19774b1ae992006-02-10 03:06:10 +00004111**
drhd68eee02009-12-11 03:44:18 +00004112** ^This API is only available if the library was compiled with the
drh4ead1482008-06-26 18:16:05 +00004113** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
danielk1977deb802c2006-02-09 13:43:28 +00004114*/
4115int sqlite3_table_column_metadata(
4116 sqlite3 *db, /* Connection handle */
4117 const char *zDbName, /* Database name or NULL */
4118 const char *zTableName, /* Table name */
4119 const char *zColumnName, /* Column name */
4120 char const **pzDataType, /* OUTPUT: Declared data type */
4121 char const **pzCollSeq, /* OUTPUT: Collation sequence name */
4122 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
4123 int *pPrimaryKey, /* OUTPUT: True if column part of PK */
drh98c94802007-10-01 13:50:31 +00004124 int *pAutoinc /* OUTPUT: True if column is auto-increment */
danielk1977deb802c2006-02-09 13:43:28 +00004125);
4126
4127/*
drhd68eee02009-12-11 03:44:18 +00004128** CAPI3REF: Load An Extension
drh1e397f82006-06-08 15:28:43 +00004129**
drhd68eee02009-12-11 03:44:18 +00004130** ^This interface loads an SQLite extension library from the named file.
drh1e397f82006-06-08 15:28:43 +00004131**
drhd68eee02009-12-11 03:44:18 +00004132** ^The sqlite3_load_extension() interface attempts to load an
4133** SQLite extension library contained in the file zFile.
drh1e397f82006-06-08 15:28:43 +00004134**
drhd68eee02009-12-11 03:44:18 +00004135** ^The entry point is zProc.
4136** ^zProc may be 0, in which case the name of the entry point
4137** defaults to "sqlite3_extension_init".
4138** ^The sqlite3_load_extension() interface returns
4139** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
4140** ^If an error occurs and pzErrMsg is not 0, then the
4141** [sqlite3_load_extension()] interface shall attempt to
4142** fill *pzErrMsg with error message text stored in memory
4143** obtained from [sqlite3_malloc()]. The calling function
4144** should free this memory by calling [sqlite3_free()].
mihailimdc884822008-06-22 08:58:50 +00004145**
drhd68eee02009-12-11 03:44:18 +00004146** ^Extension loading must be enabled using
4147** [sqlite3_enable_load_extension()] prior to calling this API,
4148** otherwise an error will be returned.
drha94cc422009-12-03 01:01:02 +00004149**
4150** See also the [load_extension() SQL function].
drh1e397f82006-06-08 15:28:43 +00004151*/
4152int sqlite3_load_extension(
4153 sqlite3 *db, /* Load the extension into this database connection */
4154 const char *zFile, /* Name of the shared library containing extension */
4155 const char *zProc, /* Entry point. Derived from zFile if 0 */
4156 char **pzErrMsg /* Put error message here if not 0 */
4157);
4158
4159/*
drhd68eee02009-12-11 03:44:18 +00004160** CAPI3REF: Enable Or Disable Extension Loading
drh6ed48bf2007-06-14 20:57:18 +00004161**
drhd68eee02009-12-11 03:44:18 +00004162** ^So as not to open security holes in older applications that are
drh6ed48bf2007-06-14 20:57:18 +00004163** unprepared to deal with extension loading, and as a means of disabling
mihailimdc884822008-06-22 08:58:50 +00004164** extension loading while evaluating user-entered SQL, the following API
4165** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
drhc2e87a32006-06-27 15:16:14 +00004166**
drhd68eee02009-12-11 03:44:18 +00004167** ^Extension loading is off by default. See ticket #1863.
4168** ^Call the sqlite3_enable_load_extension() routine with onoff==1
4169** to turn extension loading on and call it with onoff==0 to turn
4170** it back off again.
drhc2e87a32006-06-27 15:16:14 +00004171*/
4172int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
4173
4174/*
drhd68eee02009-12-11 03:44:18 +00004175** CAPI3REF: Automatically Load An Extensions
drh9eff6162006-06-12 21:59:13 +00004176**
drhd68eee02009-12-11 03:44:18 +00004177** ^This API can be invoked at program startup in order to register
drh1409be62006-08-23 20:07:20 +00004178** one or more statically linked extensions that will be available
drhd68eee02009-12-11 03:44:18 +00004179** to all new [database connections].
mihailimdc884822008-06-22 08:58:50 +00004180**
drhd68eee02009-12-11 03:44:18 +00004181** ^(This routine stores a pointer to the extension entry point
4182** in an array that is obtained from [sqlite3_malloc()]. That memory
4183** is deallocated by [sqlite3_reset_auto_extension()].)^
mihailimdc884822008-06-22 08:58:50 +00004184**
drhd68eee02009-12-11 03:44:18 +00004185** ^This function registers an extension entry point that is
4186** automatically invoked whenever a new [database connection]
4187** is opened using [sqlite3_open()], [sqlite3_open16()],
4188** or [sqlite3_open_v2()].
4189** ^Duplicate extensions are detected so calling this routine
4190** multiple times with the same extension is harmless.
4191** ^Automatic extensions apply across all threads.
drh1409be62006-08-23 20:07:20 +00004192*/
drh1875f7a2008-12-08 18:19:17 +00004193int sqlite3_auto_extension(void (*xEntryPoint)(void));
drh1409be62006-08-23 20:07:20 +00004194
drh1409be62006-08-23 20:07:20 +00004195/*
drhd68eee02009-12-11 03:44:18 +00004196** CAPI3REF: Reset Automatic Extension Loading
drh1409be62006-08-23 20:07:20 +00004197**
drhd68eee02009-12-11 03:44:18 +00004198** ^(This function disables all previously registered automatic
4199** extensions. It undoes the effect of all prior
4200** [sqlite3_auto_extension()] calls.)^
drh6ed48bf2007-06-14 20:57:18 +00004201**
drhd68eee02009-12-11 03:44:18 +00004202** ^This function disables automatic extensions in all threads.
drh1409be62006-08-23 20:07:20 +00004203*/
4204void sqlite3_reset_auto_extension(void);
4205
drh1409be62006-08-23 20:07:20 +00004206/*
drh9eff6162006-06-12 21:59:13 +00004207** The interface to the virtual-table mechanism is currently considered
4208** to be experimental. The interface might change in incompatible ways.
4209** If this is a problem for you, do not use the interface at this time.
4210**
shane26b34032008-05-23 17:21:09 +00004211** When the virtual-table mechanism stabilizes, we will declare the
drh9eff6162006-06-12 21:59:13 +00004212** interface fixed, support it indefinitely, and remove this comment.
4213*/
4214
4215/*
4216** Structures used by the virtual table interface
drhe09daa92006-06-10 13:29:31 +00004217*/
4218typedef struct sqlite3_vtab sqlite3_vtab;
4219typedef struct sqlite3_index_info sqlite3_index_info;
4220typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
4221typedef struct sqlite3_module sqlite3_module;
drh9eff6162006-06-12 21:59:13 +00004222
4223/*
drhd68eee02009-12-11 03:44:18 +00004224** CAPI3REF: Virtual Table Object
drh9cff9dc2009-04-13 14:43:40 +00004225** KEYWORDS: sqlite3_module {virtual table module}
drhb4d58ae2008-02-21 20:17:06 +00004226**
drh9cff9dc2009-04-13 14:43:40 +00004227** This structure, sometimes called a a "virtual table module",
4228** defines the implementation of a [virtual tables].
4229** This structure consists mostly of methods for the module.
mihailim15194222008-06-22 09:55:14 +00004230**
drhd68eee02009-12-11 03:44:18 +00004231** ^A virtual table module is created by filling in a persistent
drh9cff9dc2009-04-13 14:43:40 +00004232** instance of this structure and passing a pointer to that instance
4233** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
drhd68eee02009-12-11 03:44:18 +00004234** ^The registration remains valid until it is replaced by a different
drh9cff9dc2009-04-13 14:43:40 +00004235** module or until the [database connection] closes. The content
4236** of this structure must not change while it is registered with
4237** any database connection.
drh9eff6162006-06-12 21:59:13 +00004238*/
drhe09daa92006-06-10 13:29:31 +00004239struct sqlite3_module {
4240 int iVersion;
danielk19779da9d472006-06-14 06:58:15 +00004241 int (*xCreate)(sqlite3*, void *pAux,
drhe4102962006-09-11 00:34:22 +00004242 int argc, const char *const*argv,
drh4ca8aac2006-09-10 17:31:58 +00004243 sqlite3_vtab **ppVTab, char**);
danielk19779da9d472006-06-14 06:58:15 +00004244 int (*xConnect)(sqlite3*, void *pAux,
drhe4102962006-09-11 00:34:22 +00004245 int argc, const char *const*argv,
drh4ca8aac2006-09-10 17:31:58 +00004246 sqlite3_vtab **ppVTab, char**);
drhe09daa92006-06-10 13:29:31 +00004247 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
4248 int (*xDisconnect)(sqlite3_vtab *pVTab);
4249 int (*xDestroy)(sqlite3_vtab *pVTab);
4250 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
4251 int (*xClose)(sqlite3_vtab_cursor*);
drh4be8b512006-06-13 23:51:34 +00004252 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
drhe09daa92006-06-10 13:29:31 +00004253 int argc, sqlite3_value **argv);
4254 int (*xNext)(sqlite3_vtab_cursor*);
danielk1977a298e902006-06-22 09:53:48 +00004255 int (*xEof)(sqlite3_vtab_cursor*);
drhe09daa92006-06-10 13:29:31 +00004256 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
drh6d2069d2007-08-14 01:58:53 +00004257 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
4258 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
drhe09daa92006-06-10 13:29:31 +00004259 int (*xBegin)(sqlite3_vtab *pVTab);
4260 int (*xSync)(sqlite3_vtab *pVTab);
4261 int (*xCommit)(sqlite3_vtab *pVTab);
4262 int (*xRollback)(sqlite3_vtab *pVTab);
drhb7f6f682006-07-08 17:06:43 +00004263 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
drhe94b0c32006-07-08 18:09:15 +00004264 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
4265 void **ppArg);
danielk1977182c4ba2007-06-27 15:53:34 +00004266 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
drhe09daa92006-06-10 13:29:31 +00004267};
drh9eff6162006-06-12 21:59:13 +00004268
4269/*
drhd68eee02009-12-11 03:44:18 +00004270** CAPI3REF: Virtual Table Indexing Information
drhb4d58ae2008-02-21 20:17:06 +00004271** KEYWORDS: sqlite3_index_info
4272**
drh9eff6162006-06-12 21:59:13 +00004273** The sqlite3_index_info structure and its substructures is used to
drh9cff9dc2009-04-13 14:43:40 +00004274** pass information into and receive the reply from the [xBestIndex]
4275** method of a [virtual table module]. The fields under **Inputs** are the
drh9eff6162006-06-12 21:59:13 +00004276** inputs to xBestIndex and are read-only. xBestIndex inserts its
4277** results into the **Outputs** fields.
4278**
drhd68eee02009-12-11 03:44:18 +00004279** ^(The aConstraint[] array records WHERE clause constraints of the form:
drh9eff6162006-06-12 21:59:13 +00004280**
mihailim15194222008-06-22 09:55:14 +00004281** <pre>column OP expr</pre>
drh9eff6162006-06-12 21:59:13 +00004282**
drhdf6473a2009-12-13 22:20:08 +00004283** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^ ^(The particular operator is
drh7a98b852009-12-13 23:03:01 +00004284** stored in aConstraint[].op.)^ ^(The index of the column is stored in
4285** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
drh9eff6162006-06-12 21:59:13 +00004286** expr on the right-hand side can be evaluated (and thus the constraint
drhd68eee02009-12-11 03:44:18 +00004287** is usable) and false if it cannot.)^
drh9eff6162006-06-12 21:59:13 +00004288**
drhd68eee02009-12-11 03:44:18 +00004289** ^The optimizer automatically inverts terms of the form "expr OP column"
drh98c94802007-10-01 13:50:31 +00004290** and makes other simplifications to the WHERE clause in an attempt to
drh9eff6162006-06-12 21:59:13 +00004291** get as many WHERE clause terms into the form shown above as possible.
drhdf6473a2009-12-13 22:20:08 +00004292** ^The aConstraint[] array only reports WHERE clause terms that are
4293** relevant to the particular virtual table being queried.
drh9eff6162006-06-12 21:59:13 +00004294**
drhd68eee02009-12-11 03:44:18 +00004295** ^Information about the ORDER BY clause is stored in aOrderBy[].
4296** ^Each term of aOrderBy records a column of the ORDER BY clause.
drh9eff6162006-06-12 21:59:13 +00004297**
drh9cff9dc2009-04-13 14:43:40 +00004298** The [xBestIndex] method must fill aConstraintUsage[] with information
drhd68eee02009-12-11 03:44:18 +00004299** about what parameters to pass to xFilter. ^If argvIndex>0 then
drh9eff6162006-06-12 21:59:13 +00004300** the right-hand side of the corresponding aConstraint[] is evaluated
drhd68eee02009-12-11 03:44:18 +00004301** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
drh9eff6162006-06-12 21:59:13 +00004302** is true, then the constraint is assumed to be fully handled by the
drhd68eee02009-12-11 03:44:18 +00004303** virtual table and is not checked again by SQLite.)^
drh9eff6162006-06-12 21:59:13 +00004304**
drhd68eee02009-12-11 03:44:18 +00004305** ^The idxNum and idxPtr values are recorded and passed into the
drh9cff9dc2009-04-13 14:43:40 +00004306** [xFilter] method.
drh7a98b852009-12-13 23:03:01 +00004307** ^[sqlite3_free()] is used to free idxPtr if and only if
drh9cff9dc2009-04-13 14:43:40 +00004308** needToFreeIdxPtr is true.
drh9eff6162006-06-12 21:59:13 +00004309**
drhd68eee02009-12-11 03:44:18 +00004310** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
drh9eff6162006-06-12 21:59:13 +00004311** the correct order to satisfy the ORDER BY clause so that no separate
4312** sorting step is required.
4313**
drhd68eee02009-12-11 03:44:18 +00004314** ^The estimatedCost value is an estimate of the cost of doing the
drh9eff6162006-06-12 21:59:13 +00004315** particular lookup. A full scan of a table with N entries should have
4316** a cost of N. A binary search of a table of N entries should have a
4317** cost of approximately log(N).
4318*/
drhe09daa92006-06-10 13:29:31 +00004319struct sqlite3_index_info {
4320 /* Inputs */
drh6cca08c2007-09-21 12:43:16 +00004321 int nConstraint; /* Number of entries in aConstraint */
4322 struct sqlite3_index_constraint {
drh9eff6162006-06-12 21:59:13 +00004323 int iColumn; /* Column on left-hand side of constraint */
4324 unsigned char op; /* Constraint operator */
4325 unsigned char usable; /* True if this constraint is usable */
4326 int iTermOffset; /* Used internally - xBestIndex should ignore */
drh6cca08c2007-09-21 12:43:16 +00004327 } *aConstraint; /* Table of WHERE clause constraints */
4328 int nOrderBy; /* Number of terms in the ORDER BY clause */
4329 struct sqlite3_index_orderby {
drh9eff6162006-06-12 21:59:13 +00004330 int iColumn; /* Column number */
4331 unsigned char desc; /* True for DESC. False for ASC. */
drh6cca08c2007-09-21 12:43:16 +00004332 } *aOrderBy; /* The ORDER BY clause */
drhe09daa92006-06-10 13:29:31 +00004333 /* Outputs */
drh9eff6162006-06-12 21:59:13 +00004334 struct sqlite3_index_constraint_usage {
4335 int argvIndex; /* if >0, constraint is part of argv to xFilter */
4336 unsigned char omit; /* Do not code a test for this constraint */
drh6cca08c2007-09-21 12:43:16 +00004337 } *aConstraintUsage;
drh4be8b512006-06-13 23:51:34 +00004338 int idxNum; /* Number used to identify the index */
4339 char *idxStr; /* String, possibly obtained from sqlite3_malloc */
4340 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
drh9eff6162006-06-12 21:59:13 +00004341 int orderByConsumed; /* True if output is already ordered */
4342 double estimatedCost; /* Estimated cost of using this index */
drhe09daa92006-06-10 13:29:31 +00004343};
drh9eff6162006-06-12 21:59:13 +00004344#define SQLITE_INDEX_CONSTRAINT_EQ 2
4345#define SQLITE_INDEX_CONSTRAINT_GT 4
4346#define SQLITE_INDEX_CONSTRAINT_LE 8
4347#define SQLITE_INDEX_CONSTRAINT_LT 16
4348#define SQLITE_INDEX_CONSTRAINT_GE 32
4349#define SQLITE_INDEX_CONSTRAINT_MATCH 64
4350
4351/*
drhd68eee02009-12-11 03:44:18 +00004352** CAPI3REF: Register A Virtual Table Implementation
drhb4d58ae2008-02-21 20:17:06 +00004353**
drhfb434032009-12-11 23:11:26 +00004354** ^These routines are used to register a new [virtual table module] name.
drhd68eee02009-12-11 03:44:18 +00004355** ^Module names must be registered before
drhdf6473a2009-12-13 22:20:08 +00004356** creating a new [virtual table] using the module and before using a
drh9cff9dc2009-04-13 14:43:40 +00004357** preexisting [virtual table] for the module.
mihailim15194222008-06-22 09:55:14 +00004358**
drhd68eee02009-12-11 03:44:18 +00004359** ^The module name is registered on the [database connection] specified
4360** by the first parameter. ^The name of the module is given by the
4361** second parameter. ^The third parameter is a pointer to
4362** the implementation of the [virtual table module]. ^The fourth
drh9cff9dc2009-04-13 14:43:40 +00004363** parameter is an arbitrary client data pointer that is passed through
4364** into the [xCreate] and [xConnect] methods of the virtual table module
4365** when a new virtual table is be being created or reinitialized.
4366**
drhfb434032009-12-11 23:11:26 +00004367** ^The sqlite3_create_module_v2() interface has a fifth parameter which
4368** is a pointer to a destructor for the pClientData. ^SQLite will
4369** invoke the destructor function (if it is not NULL) when SQLite
4370** no longer needs the pClientData pointer. ^The sqlite3_create_module()
4371** interface is equivalent to sqlite3_create_module_v2() with a NULL
4372** destructor.
drh9eff6162006-06-12 21:59:13 +00004373*/
drh9f8da322010-03-10 20:06:37 +00004374int sqlite3_create_module(
drh9eff6162006-06-12 21:59:13 +00004375 sqlite3 *db, /* SQLite connection to register module with */
4376 const char *zName, /* Name of the module */
drh9cff9dc2009-04-13 14:43:40 +00004377 const sqlite3_module *p, /* Methods for the module */
4378 void *pClientData /* Client data for xCreate/xConnect */
drhb9bb7c12006-06-11 23:41:55 +00004379);
drh9f8da322010-03-10 20:06:37 +00004380int sqlite3_create_module_v2(
danielk1977832a58a2007-06-22 15:21:15 +00004381 sqlite3 *db, /* SQLite connection to register module with */
4382 const char *zName, /* Name of the module */
drh9cff9dc2009-04-13 14:43:40 +00004383 const sqlite3_module *p, /* Methods for the module */
4384 void *pClientData, /* Client data for xCreate/xConnect */
danielk1977832a58a2007-06-22 15:21:15 +00004385 void(*xDestroy)(void*) /* Module destructor function */
4386);
4387
4388/*
drhd68eee02009-12-11 03:44:18 +00004389** CAPI3REF: Virtual Table Instance Object
drhb4d58ae2008-02-21 20:17:06 +00004390** KEYWORDS: sqlite3_vtab
4391**
drh9cff9dc2009-04-13 14:43:40 +00004392** Every [virtual table module] implementation uses a subclass
drhd68eee02009-12-11 03:44:18 +00004393** of this object to describe a particular instance
drh9cff9dc2009-04-13 14:43:40 +00004394** of the [virtual table]. Each subclass will
mihailim15194222008-06-22 09:55:14 +00004395** be tailored to the specific needs of the module implementation.
4396** The purpose of this superclass is to define certain fields that are
4397** common to all module implementations.
drhfe1368e2006-09-10 17:08:29 +00004398**
drhd68eee02009-12-11 03:44:18 +00004399** ^Virtual tables methods can set an error message by assigning a
mihailim15194222008-06-22 09:55:14 +00004400** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
4401** take care that any prior string is freed by a call to [sqlite3_free()]
drhd68eee02009-12-11 03:44:18 +00004402** prior to assigning a new string to zErrMsg. ^After the error message
drhfe1368e2006-09-10 17:08:29 +00004403** is delivered up to the client application, the string will be automatically
drh9cff9dc2009-04-13 14:43:40 +00004404** freed by sqlite3_free() and the zErrMsg field will be zeroed.
drh9eff6162006-06-12 21:59:13 +00004405*/
4406struct sqlite3_vtab {
drha967e882006-06-13 01:04:52 +00004407 const sqlite3_module *pModule; /* The module for this virtual table */
danielk1977595a5232009-07-24 17:58:53 +00004408 int nRef; /* NO LONGER USED */
drh4ca8aac2006-09-10 17:31:58 +00004409 char *zErrMsg; /* Error message from sqlite3_mprintf() */
drh9eff6162006-06-12 21:59:13 +00004410 /* Virtual table implementations will typically add additional fields */
4411};
4412
drhb4d58ae2008-02-21 20:17:06 +00004413/*
drhd68eee02009-12-11 03:44:18 +00004414** CAPI3REF: Virtual Table Cursor Object
drh9cff9dc2009-04-13 14:43:40 +00004415** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
drhb4d58ae2008-02-21 20:17:06 +00004416**
drh9cff9dc2009-04-13 14:43:40 +00004417** Every [virtual table module] implementation uses a subclass of the
4418** following structure to describe cursors that point into the
4419** [virtual table] and are used
drh9eff6162006-06-12 21:59:13 +00004420** to loop through the virtual table. Cursors are created using the
drh9cff9dc2009-04-13 14:43:40 +00004421** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
drhd68eee02009-12-11 03:44:18 +00004422** by the [sqlite3_module.xClose | xClose] method. Cursors are used
drh9cff9dc2009-04-13 14:43:40 +00004423** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
4424** of the module. Each module implementation will define
drh9eff6162006-06-12 21:59:13 +00004425** the content of a cursor structure to suit its own needs.
4426**
4427** This superclass exists in order to define fields of the cursor that
4428** are common to all implementations.
4429*/
4430struct sqlite3_vtab_cursor {
4431 sqlite3_vtab *pVtab; /* Virtual table of this cursor */
4432 /* Virtual table implementations will typically add additional fields */
4433};
4434
4435/*
drhd68eee02009-12-11 03:44:18 +00004436** CAPI3REF: Declare The Schema Of A Virtual Table
drhb4d58ae2008-02-21 20:17:06 +00004437**
drhd68eee02009-12-11 03:44:18 +00004438** ^The [xCreate] and [xConnect] methods of a
drh9cff9dc2009-04-13 14:43:40 +00004439** [virtual table module] call this interface
drh9eff6162006-06-12 21:59:13 +00004440** to declare the format (the names and datatypes of the columns) of
4441** the virtual tables they implement.
4442*/
drh9f8da322010-03-10 20:06:37 +00004443int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
drhe09daa92006-06-10 13:29:31 +00004444
4445/*
drhd68eee02009-12-11 03:44:18 +00004446** CAPI3REF: Overload A Function For A Virtual Table
drhb4d58ae2008-02-21 20:17:06 +00004447**
drhd68eee02009-12-11 03:44:18 +00004448** ^(Virtual tables can provide alternative implementations of functions
drh9cff9dc2009-04-13 14:43:40 +00004449** using the [xFindFunction] method of the [virtual table module].
4450** But global versions of those functions
drh7a98b852009-12-13 23:03:01 +00004451** must exist in order to be overloaded.)^
drhb7481e72006-09-16 21:45:14 +00004452**
drhd68eee02009-12-11 03:44:18 +00004453** ^(This API makes sure a global version of a function with a particular
drhb7481e72006-09-16 21:45:14 +00004454** name and number of parameters exists. If no such function exists
drhd68eee02009-12-11 03:44:18 +00004455** before this API is called, a new function is created.)^ ^The implementation
drhb7481e72006-09-16 21:45:14 +00004456** of the new function always causes an exception to be thrown. So
4457** the new function is not good for anything by itself. Its only
shane26b34032008-05-23 17:21:09 +00004458** purpose is to be a placeholder function that can be overloaded
drh9cff9dc2009-04-13 14:43:40 +00004459** by a [virtual table].
drhb7481e72006-09-16 21:45:14 +00004460*/
drh9f8da322010-03-10 20:06:37 +00004461int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
drhb7481e72006-09-16 21:45:14 +00004462
4463/*
drh9eff6162006-06-12 21:59:13 +00004464** The interface to the virtual-table mechanism defined above (back up
4465** to a comment remarkably similar to this one) is currently considered
4466** to be experimental. The interface might change in incompatible ways.
4467** If this is a problem for you, do not use the interface at this time.
4468**
drh98c94802007-10-01 13:50:31 +00004469** When the virtual-table mechanism stabilizes, we will declare the
drh9eff6162006-06-12 21:59:13 +00004470** interface fixed, support it indefinitely, and remove this comment.
drh9eff6162006-06-12 21:59:13 +00004471*/
4472
danielk19778cbadb02007-05-03 16:31:26 +00004473/*
drhd68eee02009-12-11 03:44:18 +00004474** CAPI3REF: A Handle To An Open BLOB
mihailim15194222008-06-22 09:55:14 +00004475** KEYWORDS: {BLOB handle} {BLOB handles}
drh6ed48bf2007-06-14 20:57:18 +00004476**
drhb4d58ae2008-02-21 20:17:06 +00004477** An instance of this object represents an open BLOB on which
mihailim1c492652008-06-21 18:02:16 +00004478** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
drhd68eee02009-12-11 03:44:18 +00004479** ^Objects of this type are created by [sqlite3_blob_open()]
mihailim15194222008-06-22 09:55:14 +00004480** and destroyed by [sqlite3_blob_close()].
drhd68eee02009-12-11 03:44:18 +00004481** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
mihailim15194222008-06-22 09:55:14 +00004482** can be used to read or write small subsections of the BLOB.
drhd68eee02009-12-11 03:44:18 +00004483** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
danielk19778cbadb02007-05-03 16:31:26 +00004484*/
danielk1977b4e9af92007-05-01 17:49:49 +00004485typedef struct sqlite3_blob sqlite3_blob;
4486
danielk19778cbadb02007-05-03 16:31:26 +00004487/*
drhfb434032009-12-11 23:11:26 +00004488** CAPI3REF: Open A BLOB For Incremental I/O
drh6ed48bf2007-06-14 20:57:18 +00004489**
drhd68eee02009-12-11 03:44:18 +00004490** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
drhf84ddc12008-03-24 12:51:46 +00004491** in row iRow, column zColumn, table zTable in database zDb;
mihailim15194222008-06-22 09:55:14 +00004492** in other words, the same BLOB that would be selected by:
danielk19778cbadb02007-05-03 16:31:26 +00004493**
drh6ed48bf2007-06-14 20:57:18 +00004494** <pre>
drh49c3d572008-12-15 22:51:38 +00004495** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
drhd68eee02009-12-11 03:44:18 +00004496** </pre>)^
danielk19778cbadb02007-05-03 16:31:26 +00004497**
drhd68eee02009-12-11 03:44:18 +00004498** ^If the flags parameter is non-zero, then the BLOB is opened for read
4499** and write access. ^If it is zero, the BLOB is opened for read access.
4500** ^It is not possible to open a column that is part of an index or primary
danfedd4802009-10-07 11:29:40 +00004501** key for writing. ^If [foreign key constraints] are enabled, it is
drhc4ad1e92009-10-10 14:29:30 +00004502** not possible to open a column that is part of a [child key] for writing.
danielk19778cbadb02007-05-03 16:31:26 +00004503**
drhd68eee02009-12-11 03:44:18 +00004504** ^Note that the database name is not the filename that contains
drhf84ddc12008-03-24 12:51:46 +00004505** the database but rather the symbolic name of the database that
drhd68eee02009-12-11 03:44:18 +00004506** appears after the AS keyword when the database is connected using [ATTACH].
4507** ^For the main database file, the database name is "main".
4508** ^For TEMP tables, the database name is "temp".
drhf84ddc12008-03-24 12:51:46 +00004509**
drhd68eee02009-12-11 03:44:18 +00004510** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
drhabda6112009-05-14 22:37:47 +00004511** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
drhd68eee02009-12-11 03:44:18 +00004512** to be a null pointer.)^
4513** ^This function sets the [database connection] error code and message
drhabda6112009-05-14 22:37:47 +00004514** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
drhd68eee02009-12-11 03:44:18 +00004515** functions. ^Note that the *ppBlob variable is always initialized in a
drhabda6112009-05-14 22:37:47 +00004516** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
4517** regardless of the success or failure of this routine.
mihailim15194222008-06-22 09:55:14 +00004518**
drhd68eee02009-12-11 03:44:18 +00004519** ^(If the row that a BLOB handle points to is modified by an
drh9de1b352008-06-26 15:04:57 +00004520** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
4521** then the BLOB handle is marked as "expired".
4522** This is true if any column of the row is changed, even a column
drhd68eee02009-12-11 03:44:18 +00004523** other than the one the BLOB handle is open on.)^
4524** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
drh9de1b352008-06-26 15:04:57 +00004525** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
drhd68eee02009-12-11 03:44:18 +00004526** ^(Changes written into a BLOB prior to the BLOB expiring are not
drhdf6473a2009-12-13 22:20:08 +00004527** rolled back by the expiration of the BLOB. Such changes will eventually
drhd68eee02009-12-11 03:44:18 +00004528** commit if the transaction continues to completion.)^
drh9de1b352008-06-26 15:04:57 +00004529**
drhd68eee02009-12-11 03:44:18 +00004530** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
4531** the opened blob. ^The size of a blob may not be changed by this
drh9e42f8a2009-08-13 20:15:29 +00004532** interface. Use the [UPDATE] SQL command to change the size of a
drhabda6112009-05-14 22:37:47 +00004533** blob.
4534**
drhd68eee02009-12-11 03:44:18 +00004535** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
drhabda6112009-05-14 22:37:47 +00004536** and the built-in [zeroblob] SQL function can be used, if desired,
4537** to create an empty, zero-filled blob in which to read or write using
4538** this interface.
4539**
4540** To avoid a resource leak, every open [BLOB handle] should eventually
4541** be released by a call to [sqlite3_blob_close()].
danielk19778cbadb02007-05-03 16:31:26 +00004542*/
danielk1977b4e9af92007-05-01 17:49:49 +00004543int sqlite3_blob_open(
4544 sqlite3*,
4545 const char *zDb,
4546 const char *zTable,
4547 const char *zColumn,
drh6d2069d2007-08-14 01:58:53 +00004548 sqlite3_int64 iRow,
danielk1977b4e9af92007-05-01 17:49:49 +00004549 int flags,
4550 sqlite3_blob **ppBlob
4551);
4552
danielk19778cbadb02007-05-03 16:31:26 +00004553/*
drhd68eee02009-12-11 03:44:18 +00004554** CAPI3REF: Close A BLOB Handle
drh6ed48bf2007-06-14 20:57:18 +00004555**
drhd68eee02009-12-11 03:44:18 +00004556** ^Closes an open [BLOB handle].
drh2dd62be2007-12-04 13:22:43 +00004557**
drhd68eee02009-12-11 03:44:18 +00004558** ^Closing a BLOB shall cause the current transaction to commit
drhf5befa02007-12-06 02:42:07 +00004559** if there are no other BLOBs, no pending prepared statements, and the
mihailim15194222008-06-22 09:55:14 +00004560** database connection is in [autocommit mode].
drhd68eee02009-12-11 03:44:18 +00004561** ^If any writes were made to the BLOB, they might be held in cache
drhabda6112009-05-14 22:37:47 +00004562** until the close operation if they will fit.
mihailim15194222008-06-22 09:55:14 +00004563**
drhd68eee02009-12-11 03:44:18 +00004564** ^(Closing the BLOB often forces the changes
drh2dd62be2007-12-04 13:22:43 +00004565** out to disk and so if any I/O errors occur, they will likely occur
drhabda6112009-05-14 22:37:47 +00004566** at the time when the BLOB is closed. Any errors that occur during
drhd68eee02009-12-11 03:44:18 +00004567** closing are reported as a non-zero return value.)^
drh2dd62be2007-12-04 13:22:43 +00004568**
drhd68eee02009-12-11 03:44:18 +00004569** ^(The BLOB is closed unconditionally. Even if this routine returns
4570** an error code, the BLOB is still closed.)^
drhb4d58ae2008-02-21 20:17:06 +00004571**
drhd68eee02009-12-11 03:44:18 +00004572** ^Calling this routine with a null pointer (such as would be returned
4573** by a failed call to [sqlite3_blob_open()]) is a harmless no-op.
danielk19778cbadb02007-05-03 16:31:26 +00004574*/
danielk1977b4e9af92007-05-01 17:49:49 +00004575int sqlite3_blob_close(sqlite3_blob *);
4576
danielk19778cbadb02007-05-03 16:31:26 +00004577/*
drhd68eee02009-12-11 03:44:18 +00004578** CAPI3REF: Return The Size Of An Open BLOB
drh6ed48bf2007-06-14 20:57:18 +00004579**
drhd68eee02009-12-11 03:44:18 +00004580** ^Returns the size in bytes of the BLOB accessible via the
4581** successfully opened [BLOB handle] in its only argument. ^The
drhabda6112009-05-14 22:37:47 +00004582** incremental blob I/O routines can only read or overwriting existing
4583** blob content; they cannot change the size of a blob.
4584**
4585** This routine only works on a [BLOB handle] which has been created
4586** by a prior successful call to [sqlite3_blob_open()] and which has not
4587** been closed by [sqlite3_blob_close()]. Passing any other pointer in
4588** to this routine results in undefined and probably undesirable behavior.
danielk19778cbadb02007-05-03 16:31:26 +00004589*/
danielk1977b4e9af92007-05-01 17:49:49 +00004590int sqlite3_blob_bytes(sqlite3_blob *);
4591
drh9eff6162006-06-12 21:59:13 +00004592/*
drhd68eee02009-12-11 03:44:18 +00004593** CAPI3REF: Read Data From A BLOB Incrementally
drh6ed48bf2007-06-14 20:57:18 +00004594**
drhd68eee02009-12-11 03:44:18 +00004595** ^(This function is used to read data from an open [BLOB handle] into a
mihailim15194222008-06-22 09:55:14 +00004596** caller-supplied buffer. N bytes of data are copied into buffer Z
drhd68eee02009-12-11 03:44:18 +00004597** from the open BLOB, starting at offset iOffset.)^
danielk19778cbadb02007-05-03 16:31:26 +00004598**
drhd68eee02009-12-11 03:44:18 +00004599** ^If offset iOffset is less than N bytes from the end of the BLOB,
4600** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
mihailim15194222008-06-22 09:55:14 +00004601** less than zero, [SQLITE_ERROR] is returned and no data is read.
drhd68eee02009-12-11 03:44:18 +00004602** ^The size of the blob (and hence the maximum value of N+iOffset)
drhabda6112009-05-14 22:37:47 +00004603** can be determined using the [sqlite3_blob_bytes()] interface.
drhf5befa02007-12-06 02:42:07 +00004604**
drhd68eee02009-12-11 03:44:18 +00004605** ^An attempt to read from an expired [BLOB handle] fails with an
drh9de1b352008-06-26 15:04:57 +00004606** error code of [SQLITE_ABORT].
4607**
drhd68eee02009-12-11 03:44:18 +00004608** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
4609** Otherwise, an [error code] or an [extended error code] is returned.)^
drhb4d58ae2008-02-21 20:17:06 +00004610**
drhabda6112009-05-14 22:37:47 +00004611** This routine only works on a [BLOB handle] which has been created
4612** by a prior successful call to [sqlite3_blob_open()] and which has not
4613** been closed by [sqlite3_blob_close()]. Passing any other pointer in
4614** to this routine results in undefined and probably undesirable behavior.
4615**
4616** See also: [sqlite3_blob_write()].
danielk19778cbadb02007-05-03 16:31:26 +00004617*/
drhb4d58ae2008-02-21 20:17:06 +00004618int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
danielk19778cbadb02007-05-03 16:31:26 +00004619
4620/*
drhd68eee02009-12-11 03:44:18 +00004621** CAPI3REF: Write Data Into A BLOB Incrementally
drh6ed48bf2007-06-14 20:57:18 +00004622**
drhd68eee02009-12-11 03:44:18 +00004623** ^This function is used to write data into an open [BLOB handle] from a
4624** caller-supplied buffer. ^N bytes of data are copied from the buffer Z
mihailim15194222008-06-22 09:55:14 +00004625** into the open BLOB, starting at offset iOffset.
danielk19778cbadb02007-05-03 16:31:26 +00004626**
drhd68eee02009-12-11 03:44:18 +00004627** ^If the [BLOB handle] passed as the first argument was not opened for
mihailim15194222008-06-22 09:55:14 +00004628** writing (the flags parameter to [sqlite3_blob_open()] was zero),
4629** this function returns [SQLITE_READONLY].
danielk19778cbadb02007-05-03 16:31:26 +00004630**
drhd68eee02009-12-11 03:44:18 +00004631** ^This function may only modify the contents of the BLOB; it is
mihailim15194222008-06-22 09:55:14 +00004632** not possible to increase the size of a BLOB using this API.
drhd68eee02009-12-11 03:44:18 +00004633** ^If offset iOffset is less than N bytes from the end of the BLOB,
4634** [SQLITE_ERROR] is returned and no data is written. ^If N is
drhf5befa02007-12-06 02:42:07 +00004635** less than zero [SQLITE_ERROR] is returned and no data is written.
drhabda6112009-05-14 22:37:47 +00004636** The size of the BLOB (and hence the maximum value of N+iOffset)
4637** can be determined using the [sqlite3_blob_bytes()] interface.
danielk19778cbadb02007-05-03 16:31:26 +00004638**
drhd68eee02009-12-11 03:44:18 +00004639** ^An attempt to write to an expired [BLOB handle] fails with an
4640** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
drh9de1b352008-06-26 15:04:57 +00004641** before the [BLOB handle] expired are not rolled back by the
4642** expiration of the handle, though of course those changes might
4643** have been overwritten by the statement that expired the BLOB handle
4644** or by other independent statements.
4645**
drhd68eee02009-12-11 03:44:18 +00004646** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
4647** Otherwise, an [error code] or an [extended error code] is returned.)^
drhb4d58ae2008-02-21 20:17:06 +00004648**
drhabda6112009-05-14 22:37:47 +00004649** This routine only works on a [BLOB handle] which has been created
4650** by a prior successful call to [sqlite3_blob_open()] and which has not
4651** been closed by [sqlite3_blob_close()]. Passing any other pointer in
4652** to this routine results in undefined and probably undesirable behavior.
4653**
4654** See also: [sqlite3_blob_read()].
danielk19778cbadb02007-05-03 16:31:26 +00004655*/
4656int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
4657
drhd84f9462007-08-15 11:28:56 +00004658/*
drhd68eee02009-12-11 03:44:18 +00004659** CAPI3REF: Virtual File System Objects
drhd84f9462007-08-15 11:28:56 +00004660**
4661** A virtual filesystem (VFS) is an [sqlite3_vfs] object
4662** that SQLite uses to interact
drhb4d58ae2008-02-21 20:17:06 +00004663** with the underlying operating system. Most SQLite builds come with a
drhd84f9462007-08-15 11:28:56 +00004664** single default VFS that is appropriate for the host computer.
4665** New VFSes can be registered and existing VFSes can be unregistered.
4666** The following interfaces are provided.
4667**
drhd68eee02009-12-11 03:44:18 +00004668** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
4669** ^Names are case sensitive.
4670** ^Names are zero-terminated UTF-8 strings.
4671** ^If there is no match, a NULL pointer is returned.
4672** ^If zVfsName is NULL then the default VFS is returned.
drhd84f9462007-08-15 11:28:56 +00004673**
drhd68eee02009-12-11 03:44:18 +00004674** ^New VFSes are registered with sqlite3_vfs_register().
4675** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
4676** ^The same VFS can be registered multiple times without injury.
4677** ^To make an existing VFS into the default VFS, register it again
drhb4d58ae2008-02-21 20:17:06 +00004678** with the makeDflt flag set. If two different VFSes with the
4679** same name are registered, the behavior is undefined. If a
drhb6f5cf32007-08-28 15:21:45 +00004680** VFS is registered with a name that is NULL or an empty string,
4681** then the behavior is undefined.
mihailim15194222008-06-22 09:55:14 +00004682**
drhd68eee02009-12-11 03:44:18 +00004683** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
4684** ^(If the default VFS is unregistered, another VFS is chosen as
4685** the default. The choice for the new VFS is arbitrary.)^
drhd84f9462007-08-15 11:28:56 +00004686*/
drhd677b3d2007-08-20 22:48:41 +00004687sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
drhd677b3d2007-08-20 22:48:41 +00004688int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
4689int sqlite3_vfs_unregister(sqlite3_vfs*);
drhd84f9462007-08-15 11:28:56 +00004690
4691/*
drhd68eee02009-12-11 03:44:18 +00004692** CAPI3REF: Mutexes
drhd84f9462007-08-15 11:28:56 +00004693**
4694** The SQLite core uses these routines for thread
danielk19774a9d1f62008-06-19 08:51:23 +00004695** synchronization. Though they are intended for internal
drhd84f9462007-08-15 11:28:56 +00004696** use by SQLite, code that links against SQLite is
4697** permitted to use any of these routines.
4698**
mihailim15194222008-06-22 09:55:14 +00004699** The SQLite source code contains multiple implementations
drh8bacf972007-08-25 16:21:29 +00004700** of these mutex routines. An appropriate implementation
drhd68eee02009-12-11 03:44:18 +00004701** is selected automatically at compile-time. ^(The following
drh8bacf972007-08-25 16:21:29 +00004702** implementations are available in the SQLite core:
drhd84f9462007-08-15 11:28:56 +00004703**
4704** <ul>
drhc7ce76a2007-08-30 14:10:30 +00004705** <li> SQLITE_MUTEX_OS2
drhd84f9462007-08-15 11:28:56 +00004706** <li> SQLITE_MUTEX_PTHREAD
drhc7ce76a2007-08-30 14:10:30 +00004707** <li> SQLITE_MUTEX_W32
drhd84f9462007-08-15 11:28:56 +00004708** <li> SQLITE_MUTEX_NOOP
drhd68eee02009-12-11 03:44:18 +00004709** </ul>)^
drhd84f9462007-08-15 11:28:56 +00004710**
drhd68eee02009-12-11 03:44:18 +00004711** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
mihailim15194222008-06-22 09:55:14 +00004712** that does no real locking and is appropriate for use in
drhd68eee02009-12-11 03:44:18 +00004713** a single-threaded application. ^The SQLITE_MUTEX_OS2,
drhc7ce76a2007-08-30 14:10:30 +00004714** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
shane26b34032008-05-23 17:21:09 +00004715** are appropriate for use on OS/2, Unix, and Windows.
mihailim15194222008-06-22 09:55:14 +00004716**
drhd68eee02009-12-11 03:44:18 +00004717** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
drh8bacf972007-08-25 16:21:29 +00004718** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
danielk19774a9d1f62008-06-19 08:51:23 +00004719** implementation is included with the library. In this case the
4720** application must supply a custom mutex implementation using the
4721** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
mihailim15194222008-06-22 09:55:14 +00004722** before calling sqlite3_initialize() or any other public sqlite3_
drhd68eee02009-12-11 03:44:18 +00004723** function that calls sqlite3_initialize().)^
drhcb041342008-06-12 00:07:29 +00004724**
drhd68eee02009-12-11 03:44:18 +00004725** ^The sqlite3_mutex_alloc() routine allocates a new
4726** mutex and returns a pointer to it. ^If it returns NULL
4727** that means that a mutex could not be allocated. ^SQLite
4728** will unwind its stack and return an error. ^(The argument
drh6bdec4a2007-08-16 19:40:16 +00004729** to sqlite3_mutex_alloc() is one of these integer constants:
4730**
4731** <ul>
4732** <li> SQLITE_MUTEX_FAST
4733** <li> SQLITE_MUTEX_RECURSIVE
4734** <li> SQLITE_MUTEX_STATIC_MASTER
4735** <li> SQLITE_MUTEX_STATIC_MEM
drh86f8c192007-08-22 00:39:19 +00004736** <li> SQLITE_MUTEX_STATIC_MEM2
drh6bdec4a2007-08-16 19:40:16 +00004737** <li> SQLITE_MUTEX_STATIC_PRNG
danielk19779f61c2f2007-08-27 17:27:49 +00004738** <li> SQLITE_MUTEX_STATIC_LRU
danielk1977dfb316d2008-03-26 18:34:43 +00004739** <li> SQLITE_MUTEX_STATIC_LRU2
drhd68eee02009-12-11 03:44:18 +00004740** </ul>)^
drh6bdec4a2007-08-16 19:40:16 +00004741**
drhd68eee02009-12-11 03:44:18 +00004742** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
4743** cause sqlite3_mutex_alloc() to create
4744** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
4745** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
drh6bdec4a2007-08-16 19:40:16 +00004746** The mutex implementation does not need to make a distinction
4747** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
drhd68eee02009-12-11 03:44:18 +00004748** not want to. ^SQLite will only request a recursive mutex in
4749** cases where it really needs one. ^If a faster non-recursive mutex
drh6bdec4a2007-08-16 19:40:16 +00004750** implementation is available on the host platform, the mutex subsystem
4751** might return such a mutex in response to SQLITE_MUTEX_FAST.
4752**
drhd68eee02009-12-11 03:44:18 +00004753** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
4754** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
4755** a pointer to a static preexisting mutex. ^Six static mutexes are
drh6bdec4a2007-08-16 19:40:16 +00004756** used by the current version of SQLite. Future versions of SQLite
4757** may add additional static mutexes. Static mutexes are for internal
4758** use by SQLite only. Applications that use SQLite mutexes should
4759** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
4760** SQLITE_MUTEX_RECURSIVE.
4761**
drhd68eee02009-12-11 03:44:18 +00004762** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
drh6bdec4a2007-08-16 19:40:16 +00004763** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
drhd68eee02009-12-11 03:44:18 +00004764** returns a different mutex on every call. ^But for the static
drh6bdec4a2007-08-16 19:40:16 +00004765** mutex types, the same mutex is returned on every call that has
mihailim04bcc002008-06-22 10:21:27 +00004766** the same type number.
drhd84f9462007-08-15 11:28:56 +00004767**
drhd68eee02009-12-11 03:44:18 +00004768** ^The sqlite3_mutex_free() routine deallocates a previously
4769** allocated dynamic mutex. ^SQLite is careful to deallocate every
4770** dynamic mutex that it allocates. The dynamic mutexes must not be in
4771** use when they are deallocated. Attempting to deallocate a static
4772** mutex results in undefined behavior. ^SQLite never deallocates
4773** a static mutex.
drhd84f9462007-08-15 11:28:56 +00004774**
drhd68eee02009-12-11 03:44:18 +00004775** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
4776** to enter a mutex. ^If another thread is already within the mutex,
drh6bdec4a2007-08-16 19:40:16 +00004777** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
drhd68eee02009-12-11 03:44:18 +00004778** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
4779** upon successful entry. ^(Mutexes created using
drhf5befa02007-12-06 02:42:07 +00004780** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
drhd68eee02009-12-11 03:44:18 +00004781** In such cases the,
drh6bdec4a2007-08-16 19:40:16 +00004782** mutex must be exited an equal number of times before another thread
drhd68eee02009-12-11 03:44:18 +00004783** can enter.)^ ^(If the same thread tries to enter any other
drhf5befa02007-12-06 02:42:07 +00004784** kind of mutex more than once, the behavior is undefined.
drhd68eee02009-12-11 03:44:18 +00004785** SQLite will never exhibit
4786** such behavior in its own use of mutexes.)^
drhd84f9462007-08-15 11:28:56 +00004787**
drhd68eee02009-12-11 03:44:18 +00004788** ^(Some systems (for example, Windows 95) do not support the operation
mihailim15194222008-06-22 09:55:14 +00004789** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
drhd68eee02009-12-11 03:44:18 +00004790** will always return SQLITE_BUSY. The SQLite core only ever uses
4791** sqlite3_mutex_try() as an optimization so this is acceptable behavior.)^
drhca49cba2007-09-04 22:31:36 +00004792**
drhd68eee02009-12-11 03:44:18 +00004793** ^The sqlite3_mutex_leave() routine exits a mutex that was
4794** previously entered by the same thread. ^(The behavior
drh8bacf972007-08-25 16:21:29 +00004795** is undefined if the mutex is not currently entered by the
drhd68eee02009-12-11 03:44:18 +00004796** calling thread or is not currently allocated. SQLite will
4797** never do either.)^
drh8bacf972007-08-25 16:21:29 +00004798**
drhd68eee02009-12-11 03:44:18 +00004799** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
drh40257ff2008-06-13 18:24:27 +00004800** sqlite3_mutex_leave() is a NULL pointer, then all three routines
4801** behave as no-ops.
4802**
drh8bacf972007-08-25 16:21:29 +00004803** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
4804*/
4805sqlite3_mutex *sqlite3_mutex_alloc(int);
4806void sqlite3_mutex_free(sqlite3_mutex*);
4807void sqlite3_mutex_enter(sqlite3_mutex*);
4808int sqlite3_mutex_try(sqlite3_mutex*);
4809void sqlite3_mutex_leave(sqlite3_mutex*);
4810
drh56a40a82008-06-18 13:47:03 +00004811/*
drhd68eee02009-12-11 03:44:18 +00004812** CAPI3REF: Mutex Methods Object
drh56a40a82008-06-18 13:47:03 +00004813**
4814** An instance of this structure defines the low-level routines
danielk19774a9d1f62008-06-19 08:51:23 +00004815** used to allocate and use mutexes.
4816**
4817** Usually, the default mutex implementations provided by SQLite are
mihailim15194222008-06-22 09:55:14 +00004818** sufficient, however the user has the option of substituting a custom
4819** implementation for specialized deployments or systems for which SQLite
danielk19774a9d1f62008-06-19 08:51:23 +00004820** does not provide a suitable implementation. In this case, the user
4821** creates and populates an instance of this structure to pass
mihailim15194222008-06-22 09:55:14 +00004822** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
danielk19774a9d1f62008-06-19 08:51:23 +00004823** Additionally, an instance of this structure can be used as an
4824** output variable when querying the system for the current mutex
4825** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
4826**
drhd68eee02009-12-11 03:44:18 +00004827** ^The xMutexInit method defined by this structure is invoked as
danielk19774a9d1f62008-06-19 08:51:23 +00004828** part of system initialization by the sqlite3_initialize() function.
drhd68eee02009-12-11 03:44:18 +00004829** ^The xMutexInit routine is calle by SQLite exactly once for each
mihailim15194222008-06-22 09:55:14 +00004830** effective call to [sqlite3_initialize()].
danielk19774a9d1f62008-06-19 08:51:23 +00004831**
drhd68eee02009-12-11 03:44:18 +00004832** ^The xMutexEnd method defined by this structure is invoked as
danielk19774a9d1f62008-06-19 08:51:23 +00004833** part of system shutdown by the sqlite3_shutdown() function. The
4834** implementation of this method is expected to release all outstanding
4835** resources obtained by the mutex methods implementation, especially
drhd68eee02009-12-11 03:44:18 +00004836** those obtained by the xMutexInit method. ^The xMutexEnd()
4837** interface is invoked exactly once for each call to [sqlite3_shutdown()].
danielk19774a9d1f62008-06-19 08:51:23 +00004838**
drhd68eee02009-12-11 03:44:18 +00004839** ^(The remaining seven methods defined by this structure (xMutexAlloc,
danielk19774a9d1f62008-06-19 08:51:23 +00004840** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
4841** xMutexNotheld) implement the following interfaces (respectively):
drh56a40a82008-06-18 13:47:03 +00004842**
4843** <ul>
danielk19774a9d1f62008-06-19 08:51:23 +00004844** <li> [sqlite3_mutex_alloc()] </li>
4845** <li> [sqlite3_mutex_free()] </li>
4846** <li> [sqlite3_mutex_enter()] </li>
4847** <li> [sqlite3_mutex_try()] </li>
4848** <li> [sqlite3_mutex_leave()] </li>
4849** <li> [sqlite3_mutex_held()] </li>
4850** <li> [sqlite3_mutex_notheld()] </li>
drhd68eee02009-12-11 03:44:18 +00004851** </ul>)^
danielk19774a9d1f62008-06-19 08:51:23 +00004852**
4853** The only difference is that the public sqlite3_XXX functions enumerated
4854** above silently ignore any invocations that pass a NULL pointer instead
4855** of a valid mutex handle. The implementations of the methods defined
4856** by this structure are not required to handle this case, the results
4857** of passing a NULL pointer instead of a valid mutex handle are undefined
4858** (i.e. it is acceptable to provide an implementation that segfaults if
4859** it is passed a NULL pointer).
drh9ac06502009-08-17 13:42:29 +00004860**
drhd68eee02009-12-11 03:44:18 +00004861** The xMutexInit() method must be threadsafe. ^It must be harmless to
drh9ac06502009-08-17 13:42:29 +00004862** invoke xMutexInit() mutiple times within the same process and without
4863** intervening calls to xMutexEnd(). Second and subsequent calls to
4864** xMutexInit() must be no-ops.
4865**
drhd68eee02009-12-11 03:44:18 +00004866** ^xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
4867** and its associates). ^Similarly, xMutexAlloc() must not use SQLite memory
4868** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
drh9ac06502009-08-17 13:42:29 +00004869** memory allocation for a fast or recursive mutex.
4870**
drhd68eee02009-12-11 03:44:18 +00004871** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
drh9ac06502009-08-17 13:42:29 +00004872** called, but only if the prior call to xMutexInit returned SQLITE_OK.
4873** If xMutexInit fails in any way, it is expected to clean up after itself
4874** prior to returning.
drh56a40a82008-06-18 13:47:03 +00004875*/
danielk19776d2ab0e2008-06-17 17:21:18 +00004876typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
4877struct sqlite3_mutex_methods {
4878 int (*xMutexInit)(void);
danielk19774a9d1f62008-06-19 08:51:23 +00004879 int (*xMutexEnd)(void);
danielk19776d2ab0e2008-06-17 17:21:18 +00004880 sqlite3_mutex *(*xMutexAlloc)(int);
4881 void (*xMutexFree)(sqlite3_mutex *);
4882 void (*xMutexEnter)(sqlite3_mutex *);
4883 int (*xMutexTry)(sqlite3_mutex *);
4884 void (*xMutexLeave)(sqlite3_mutex *);
danielk19776d2ab0e2008-06-17 17:21:18 +00004885 int (*xMutexHeld)(sqlite3_mutex *);
4886 int (*xMutexNotheld)(sqlite3_mutex *);
4887};
4888
drh8bacf972007-08-25 16:21:29 +00004889/*
drhd68eee02009-12-11 03:44:18 +00004890** CAPI3REF: Mutex Verification Routines
drhd677b3d2007-08-20 22:48:41 +00004891**
4892** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
drhd68eee02009-12-11 03:44:18 +00004893** are intended for use inside assert() statements. ^The SQLite core
drhf77a2ff2007-08-25 14:49:36 +00004894** never uses these routines except inside an assert() and applications
drhd68eee02009-12-11 03:44:18 +00004895** are advised to follow the lead of the core. ^The SQLite core only
drh8bacf972007-08-25 16:21:29 +00004896** provides implementations for these routines when it is compiled
drhd68eee02009-12-11 03:44:18 +00004897** with the SQLITE_DEBUG flag. ^External mutex implementations
drh8bacf972007-08-25 16:21:29 +00004898** are only required to provide these routines if SQLITE_DEBUG is
4899** defined and if NDEBUG is not defined.
4900**
drhd68eee02009-12-11 03:44:18 +00004901** ^These routines should return true if the mutex in their argument
mihailim04bcc002008-06-22 10:21:27 +00004902** is held or not held, respectively, by the calling thread.
drh8bacf972007-08-25 16:21:29 +00004903**
drhd68eee02009-12-11 03:44:18 +00004904** ^The implementation is not required to provided versions of these
mihailim04bcc002008-06-22 10:21:27 +00004905** routines that actually work. If the implementation does not provide working
4906** versions of these routines, it should at least provide stubs that always
4907** return true so that one does not get spurious assertion failures.
drhd677b3d2007-08-20 22:48:41 +00004908**
drhd68eee02009-12-11 03:44:18 +00004909** ^If the argument to sqlite3_mutex_held() is a NULL pointer then
4910** the routine should return 1. This seems counter-intuitive since
drhd677b3d2007-08-20 22:48:41 +00004911** clearly the mutex cannot be held if it does not exist. But the
4912** the reason the mutex does not exist is because the build is not
4913** using mutexes. And we do not want the assert() containing the
4914** call to sqlite3_mutex_held() to fail, so a non-zero return is
drhd68eee02009-12-11 03:44:18 +00004915** the appropriate thing to do. ^The sqlite3_mutex_notheld()
drhd677b3d2007-08-20 22:48:41 +00004916** interface should also return 1 when given a NULL pointer.
drhd84f9462007-08-15 11:28:56 +00004917*/
drh0edb3cf2009-12-10 01:17:29 +00004918#ifndef NDEBUG
drhd677b3d2007-08-20 22:48:41 +00004919int sqlite3_mutex_held(sqlite3_mutex*);
4920int sqlite3_mutex_notheld(sqlite3_mutex*);
drh0edb3cf2009-12-10 01:17:29 +00004921#endif
drh32bc3f62007-08-21 20:25:39 +00004922
4923/*
drhd68eee02009-12-11 03:44:18 +00004924** CAPI3REF: Mutex Types
drh32bc3f62007-08-21 20:25:39 +00004925**
drhd5a68d32008-08-04 13:44:57 +00004926** The [sqlite3_mutex_alloc()] interface takes a single argument
mihailim04bcc002008-06-22 10:21:27 +00004927** which is one of these integer constants.
drhd5a68d32008-08-04 13:44:57 +00004928**
4929** The set of static mutexes may change from one SQLite release to the
4930** next. Applications that override the built-in mutex logic must be
4931** prepared to accommodate additional static mutexes.
drh32bc3f62007-08-21 20:25:39 +00004932*/
drh6bdec4a2007-08-16 19:40:16 +00004933#define SQLITE_MUTEX_FAST 0
4934#define SQLITE_MUTEX_RECURSIVE 1
4935#define SQLITE_MUTEX_STATIC_MASTER 2
drh86f8c192007-08-22 00:39:19 +00004936#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
drh7555d8e2009-03-20 13:15:30 +00004937#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
4938#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
drh86f8c192007-08-22 00:39:19 +00004939#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
danielk19779f61c2f2007-08-27 17:27:49 +00004940#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
danielk1977dfb316d2008-03-26 18:34:43 +00004941#define SQLITE_MUTEX_STATIC_LRU2 7 /* lru page list */
drh6d2069d2007-08-14 01:58:53 +00004942
drhcc6bb3e2007-08-31 16:11:35 +00004943/*
drhd68eee02009-12-11 03:44:18 +00004944** CAPI3REF: Retrieve the mutex for a database connection
drh4413d0e2008-11-04 13:46:27 +00004945**
drhd68eee02009-12-11 03:44:18 +00004946** ^This interface returns a pointer the [sqlite3_mutex] object that
drh4413d0e2008-11-04 13:46:27 +00004947** serializes access to the [database connection] given in the argument
4948** when the [threading mode] is Serialized.
drhd68eee02009-12-11 03:44:18 +00004949** ^If the [threading mode] is Single-thread or Multi-thread then this
drh4413d0e2008-11-04 13:46:27 +00004950** routine returns a NULL pointer.
4951*/
4952sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
4953
4954/*
drhfb434032009-12-11 23:11:26 +00004955** CAPI3REF: Low-Level Control Of Database Files
drhcc6bb3e2007-08-31 16:11:35 +00004956**
drhd68eee02009-12-11 03:44:18 +00004957** ^The [sqlite3_file_control()] interface makes a direct call to the
drhcc6bb3e2007-08-31 16:11:35 +00004958** xFileControl method for the [sqlite3_io_methods] object associated
drhd68eee02009-12-11 03:44:18 +00004959** with a particular database identified by the second argument. ^The
4960** name of the database "main" for the main database or "temp" for the
4961** TEMP database, or the name that appears after the AS keyword for
4962** databases that are added using the [ATTACH] SQL command.
4963** ^A NULL pointer can be used in place of "main" to refer to the
4964** main database file.
4965** ^The third and fourth parameters to this routine
drhcc6bb3e2007-08-31 16:11:35 +00004966** are passed directly through to the second and third parameters of
drhd68eee02009-12-11 03:44:18 +00004967** the xFileControl method. ^The return value of the xFileControl
drhcc6bb3e2007-08-31 16:11:35 +00004968** method becomes the return value of this routine.
4969**
drhd68eee02009-12-11 03:44:18 +00004970** ^If the second parameter (zDbName) does not match the name of any
4971** open database file, then SQLITE_ERROR is returned. ^This error
drhcc6bb3e2007-08-31 16:11:35 +00004972** code is not remembered and will not be recalled by [sqlite3_errcode()]
drhd68eee02009-12-11 03:44:18 +00004973** or [sqlite3_errmsg()]. The underlying xFileControl method might
4974** also return SQLITE_ERROR. There is no way to distinguish between
drhcc6bb3e2007-08-31 16:11:35 +00004975** an incorrect zDbName and an SQLITE_ERROR return from the underlying
drhd68eee02009-12-11 03:44:18 +00004976** xFileControl method.
drh4ff7fa02007-09-01 18:17:21 +00004977**
4978** See also: [SQLITE_FCNTL_LOCKSTATE]
drhcc6bb3e2007-08-31 16:11:35 +00004979*/
4980int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
drh6d2069d2007-08-14 01:58:53 +00004981
danielk19778cbadb02007-05-03 16:31:26 +00004982/*
drhd68eee02009-12-11 03:44:18 +00004983** CAPI3REF: Testing Interface
drhed13d982008-01-31 14:43:24 +00004984**
drhd68eee02009-12-11 03:44:18 +00004985** ^The sqlite3_test_control() interface is used to read out internal
drhed13d982008-01-31 14:43:24 +00004986** state of SQLite and to inject faults into SQLite for testing
drhd68eee02009-12-11 03:44:18 +00004987** purposes. ^The first parameter is an operation code that determines
drhed13d982008-01-31 14:43:24 +00004988** the number, meaning, and operation of all subsequent parameters.
4989**
4990** This interface is not for use by applications. It exists solely
4991** for verifying the correct operation of the SQLite library. Depending
4992** on how the SQLite library is compiled, this interface might not exist.
4993**
4994** The details of the operation codes, their meanings, the parameters
4995** they take, and what they do are all subject to change without notice.
4996** Unlike most of the SQLite API, this function is not guaranteed to
4997** operate consistently from one release to the next.
4998*/
4999int sqlite3_test_control(int op, ...);
5000
5001/*
drhd68eee02009-12-11 03:44:18 +00005002** CAPI3REF: Testing Interface Operation Codes
drhed13d982008-01-31 14:43:24 +00005003**
5004** These constants are the valid operation code parameters used
5005** as the first argument to [sqlite3_test_control()].
5006**
shane26b34032008-05-23 17:21:09 +00005007** These parameters and their meanings are subject to change
drhed13d982008-01-31 14:43:24 +00005008** without notice. These values are for testing purposes only.
5009** Applications should not use any of these parameters or the
5010** [sqlite3_test_control()] interface.
5011*/
drh07096f62009-12-22 23:52:32 +00005012#define SQLITE_TESTCTRL_FIRST 5
drh2fa18682008-03-19 14:15:34 +00005013#define SQLITE_TESTCTRL_PRNG_SAVE 5
5014#define SQLITE_TESTCTRL_PRNG_RESTORE 6
5015#define SQLITE_TESTCTRL_PRNG_RESET 7
drh3088d592008-03-21 16:45:47 +00005016#define SQLITE_TESTCTRL_BITVEC_TEST 8
danielk1977d09414c2008-06-19 18:17:49 +00005017#define SQLITE_TESTCTRL_FAULT_INSTALL 9
danielk19772d1d86f2008-06-20 14:59:51 +00005018#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
drhc7a3bb92009-02-05 16:31:45 +00005019#define SQLITE_TESTCTRL_PENDING_BYTE 11
drhf3af63f2009-05-09 18:59:42 +00005020#define SQLITE_TESTCTRL_ASSERT 12
5021#define SQLITE_TESTCTRL_ALWAYS 13
drhc046e3e2009-07-15 11:26:44 +00005022#define SQLITE_TESTCTRL_RESERVE 14
drh07096f62009-12-22 23:52:32 +00005023#define SQLITE_TESTCTRL_OPTIMIZATIONS 15
drh0e857732010-01-02 03:21:35 +00005024#define SQLITE_TESTCTRL_ISKEYWORD 16
5025#define SQLITE_TESTCTRL_LAST 16
drhed13d982008-01-31 14:43:24 +00005026
drhf7141992008-06-19 00:16:08 +00005027/*
drhd68eee02009-12-11 03:44:18 +00005028** CAPI3REF: SQLite Runtime Status
drhf7141992008-06-19 00:16:08 +00005029**
drhd68eee02009-12-11 03:44:18 +00005030** ^This interface is used to retrieve runtime status information
drhf7141992008-06-19 00:16:08 +00005031** about the preformance of SQLite, and optionally to reset various
drhd68eee02009-12-11 03:44:18 +00005032** highwater marks. ^The first argument is an integer code for
drhdf6473a2009-12-13 22:20:08 +00005033** the specific parameter to measure. ^(Recognized integer codes
5034** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].)^
drhd68eee02009-12-11 03:44:18 +00005035** ^The current value of the parameter is returned into *pCurrent.
5036** ^The highest recorded value is returned in *pHighwater. ^If the
drhf7141992008-06-19 00:16:08 +00005037** resetFlag is true, then the highest record value is reset after
drhd68eee02009-12-11 03:44:18 +00005038** *pHighwater is written. ^(Some parameters do not record the highest
drhf7141992008-06-19 00:16:08 +00005039** value. For those parameters
drhd68eee02009-12-11 03:44:18 +00005040** nothing is written into *pHighwater and the resetFlag is ignored.)^
5041** ^(Other parameters record only the highwater mark and not the current
5042** value. For these latter parameters nothing is written into *pCurrent.)^
drhf7141992008-06-19 00:16:08 +00005043**
drhd68eee02009-12-11 03:44:18 +00005044** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
5045** non-zero [error code] on failure.
drhf7141992008-06-19 00:16:08 +00005046**
drh6aa5f152009-08-19 15:57:07 +00005047** This routine is threadsafe but is not atomic. This routine can be
drhf7141992008-06-19 00:16:08 +00005048** called while other threads are running the same or different SQLite
5049** interfaces. However the values returned in *pCurrent and
5050** *pHighwater reflect the status of SQLite at different points in time
5051** and it is possible that another thread might change the parameter
5052** in between the times when *pCurrent and *pHighwater are written.
5053**
drh2462e322008-07-31 14:47:54 +00005054** See also: [sqlite3_db_status()]
drhf7141992008-06-19 00:16:08 +00005055*/
drh9f8da322010-03-10 20:06:37 +00005056int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
drh2462e322008-07-31 14:47:54 +00005057
danielk1977075c23a2008-09-01 18:34:20 +00005058
drhf7141992008-06-19 00:16:08 +00005059/*
drhd68eee02009-12-11 03:44:18 +00005060** CAPI3REF: Status Parameters
drhf7141992008-06-19 00:16:08 +00005061**
5062** These integer constants designate various run-time status parameters
5063** that can be returned by [sqlite3_status()].
5064**
5065** <dl>
drhd68eee02009-12-11 03:44:18 +00005066** ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
drhf7141992008-06-19 00:16:08 +00005067** <dd>This parameter is the current amount of memory checked out
mihailim15194222008-06-22 09:55:14 +00005068** using [sqlite3_malloc()], either directly or indirectly. The
drhf7141992008-06-19 00:16:08 +00005069** figure includes calls made to [sqlite3_malloc()] by the application
5070** and internal memory usage by the SQLite library. Scratch memory
5071** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
5072** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
5073** this parameter. The amount returned is the sum of the allocation
drhd68eee02009-12-11 03:44:18 +00005074** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
drhf7141992008-06-19 00:16:08 +00005075**
drhd68eee02009-12-11 03:44:18 +00005076** ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
drhe50135e2008-08-05 17:53:22 +00005077** <dd>This parameter records the largest memory allocation request
5078** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
5079** internal equivalents). Only the value returned in the
5080** *pHighwater parameter to [sqlite3_status()] is of interest.
drhd68eee02009-12-11 03:44:18 +00005081** The value written into the *pCurrent parameter is undefined.</dd>)^
drhe50135e2008-08-05 17:53:22 +00005082**
drhd68eee02009-12-11 03:44:18 +00005083** ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
drhf7141992008-06-19 00:16:08 +00005084** <dd>This parameter returns the number of pages used out of the
drhe50135e2008-08-05 17:53:22 +00005085** [pagecache memory allocator] that was configured using
5086** [SQLITE_CONFIG_PAGECACHE]. The
drhd68eee02009-12-11 03:44:18 +00005087** value returned is in pages, not in bytes.</dd>)^
drhf7141992008-06-19 00:16:08 +00005088**
drhd68eee02009-12-11 03:44:18 +00005089** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
drhf7141992008-06-19 00:16:08 +00005090** <dd>This parameter returns the number of bytes of page cache
5091** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
drhe50135e2008-08-05 17:53:22 +00005092** buffer and where forced to overflow to [sqlite3_malloc()]. The
5093** returned value includes allocations that overflowed because they
5094** where too large (they were larger than the "sz" parameter to
5095** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
drhd68eee02009-12-11 03:44:18 +00005096** no space was left in the page cache.</dd>)^
drhe50135e2008-08-05 17:53:22 +00005097**
drhd68eee02009-12-11 03:44:18 +00005098** ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
drhe50135e2008-08-05 17:53:22 +00005099** <dd>This parameter records the largest memory allocation request
5100** handed to [pagecache memory allocator]. Only the value returned in the
5101** *pHighwater parameter to [sqlite3_status()] is of interest.
drhd68eee02009-12-11 03:44:18 +00005102** The value written into the *pCurrent parameter is undefined.</dd>)^
drhf7141992008-06-19 00:16:08 +00005103**
drhd68eee02009-12-11 03:44:18 +00005104** ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>
drhf7141992008-06-19 00:16:08 +00005105** <dd>This parameter returns the number of allocations used out of the
drhe50135e2008-08-05 17:53:22 +00005106** [scratch memory allocator] configured using
drhf7141992008-06-19 00:16:08 +00005107** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
drhe50135e2008-08-05 17:53:22 +00005108** in bytes. Since a single thread may only have one scratch allocation
drhf7141992008-06-19 00:16:08 +00005109** outstanding at time, this parameter also reports the number of threads
drhd68eee02009-12-11 03:44:18 +00005110** using scratch memory at the same time.</dd>)^
drhf7141992008-06-19 00:16:08 +00005111**
drhd68eee02009-12-11 03:44:18 +00005112** ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
drhf7141992008-06-19 00:16:08 +00005113** <dd>This parameter returns the number of bytes of scratch memory
5114** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
drhe50135e2008-08-05 17:53:22 +00005115** buffer and where forced to overflow to [sqlite3_malloc()]. The values
5116** returned include overflows because the requested allocation was too
5117** larger (that is, because the requested allocation was larger than the
5118** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
5119** slots were available.
drhd68eee02009-12-11 03:44:18 +00005120** </dd>)^
drhf7141992008-06-19 00:16:08 +00005121**
drhd68eee02009-12-11 03:44:18 +00005122** ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
drhf7141992008-06-19 00:16:08 +00005123** <dd>This parameter records the largest memory allocation request
drhe50135e2008-08-05 17:53:22 +00005124** handed to [scratch memory allocator]. Only the value returned in the
5125** *pHighwater parameter to [sqlite3_status()] is of interest.
drhd68eee02009-12-11 03:44:18 +00005126** The value written into the *pCurrent parameter is undefined.</dd>)^
drhec424a52008-07-25 15:39:03 +00005127**
drhd68eee02009-12-11 03:44:18 +00005128** ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
drhec424a52008-07-25 15:39:03 +00005129** <dd>This parameter records the deepest parser stack. It is only
drhd68eee02009-12-11 03:44:18 +00005130** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
drhf7141992008-06-19 00:16:08 +00005131** </dl>
5132**
5133** New status parameters may be added from time to time.
5134*/
5135#define SQLITE_STATUS_MEMORY_USED 0
5136#define SQLITE_STATUS_PAGECACHE_USED 1
5137#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
5138#define SQLITE_STATUS_SCRATCH_USED 3
5139#define SQLITE_STATUS_SCRATCH_OVERFLOW 4
5140#define SQLITE_STATUS_MALLOC_SIZE 5
drhec424a52008-07-25 15:39:03 +00005141#define SQLITE_STATUS_PARSER_STACK 6
drhe50135e2008-08-05 17:53:22 +00005142#define SQLITE_STATUS_PAGECACHE_SIZE 7
5143#define SQLITE_STATUS_SCRATCH_SIZE 8
drhf7141992008-06-19 00:16:08 +00005144
drh633e6d52008-07-28 19:34:53 +00005145/*
drhd68eee02009-12-11 03:44:18 +00005146** CAPI3REF: Database Connection Status
drhd1d38482008-10-07 23:46:38 +00005147**
drhd68eee02009-12-11 03:44:18 +00005148** ^This interface is used to retrieve runtime status information
5149** about a single [database connection]. ^The first argument is the
5150** database connection object to be interrogated. ^The second argument
drh63da0892010-03-10 21:42:07 +00005151** is an integer constant, taken from the set of
5152** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros, that
5153** determiness the parameter to interrogate. The set of
5154** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros is likely
5155** to grow in future releases of SQLite.
drhd1d38482008-10-07 23:46:38 +00005156**
drhd68eee02009-12-11 03:44:18 +00005157** ^The current value of the requested parameter is written into *pCur
5158** and the highest instantaneous value is written into *pHiwtr. ^If
drhd1d38482008-10-07 23:46:38 +00005159** the resetFlg is true, then the highest instantaneous value is
5160** reset back down to the current value.
5161**
5162** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
5163*/
drh9f8da322010-03-10 20:06:37 +00005164int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
drhd1d38482008-10-07 23:46:38 +00005165
5166/*
drhd68eee02009-12-11 03:44:18 +00005167** CAPI3REF: Status Parameters for database connections
drh633e6d52008-07-28 19:34:53 +00005168**
drh6aa5f152009-08-19 15:57:07 +00005169** These constants are the available integer "verbs" that can be passed as
5170** the second argument to the [sqlite3_db_status()] interface.
5171**
5172** New verbs may be added in future releases of SQLite. Existing verbs
5173** might be discontinued. Applications should check the return code from
5174** [sqlite3_db_status()] to make sure that the call worked.
5175** The [sqlite3_db_status()] interface will return a non-zero error code
5176** if a discontinued or unsupported verb is invoked.
drh633e6d52008-07-28 19:34:53 +00005177**
5178** <dl>
drhd68eee02009-12-11 03:44:18 +00005179** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
drh633e6d52008-07-28 19:34:53 +00005180** <dd>This parameter returns the number of lookaside memory slots currently
drhd68eee02009-12-11 03:44:18 +00005181** checked out.</dd>)^
drh63da0892010-03-10 21:42:07 +00005182**
5183** <dt>SQLITE_DBSTATUS_CACHE_USED</dt>
5184** <dd>^This parameter returns the approximate number of of bytes of heap
5185** memory used by all pager caches associated with the database connection.
5186** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
5187** checked out.</dd>)^
drh633e6d52008-07-28 19:34:53 +00005188** </dl>
5189*/
5190#define SQLITE_DBSTATUS_LOOKASIDE_USED 0
drh63da0892010-03-10 21:42:07 +00005191#define SQLITE_DBSTATUS_CACHE_USED 1
5192#define SQLITE_DBSTATUS_MAX 1 /* Largest defined DBSTATUS */
drhed13d982008-01-31 14:43:24 +00005193
drhd1d38482008-10-07 23:46:38 +00005194
5195/*
drhd68eee02009-12-11 03:44:18 +00005196** CAPI3REF: Prepared Statement Status
drhd1d38482008-10-07 23:46:38 +00005197**
drhd68eee02009-12-11 03:44:18 +00005198** ^(Each prepared statement maintains various
drhd1d38482008-10-07 23:46:38 +00005199** [SQLITE_STMTSTATUS_SORT | counters] that measure the number
drh9be37f62009-12-12 23:57:36 +00005200** of times it has performed specific operations.)^ These counters can
drhd1d38482008-10-07 23:46:38 +00005201** be used to monitor the performance characteristics of the prepared
5202** statements. For example, if the number of table steps greatly exceeds
5203** the number of table searches or result rows, that would tend to indicate
5204** that the prepared statement is using a full table scan rather than
5205** an index.
5206**
drhd68eee02009-12-11 03:44:18 +00005207** ^(This interface is used to retrieve and reset counter values from
drhd1d38482008-10-07 23:46:38 +00005208** a [prepared statement]. The first argument is the prepared statement
5209** object to be interrogated. The second argument
5210** is an integer code for a specific [SQLITE_STMTSTATUS_SORT | counter]
drhd68eee02009-12-11 03:44:18 +00005211** to be interrogated.)^
5212** ^The current value of the requested counter is returned.
5213** ^If the resetFlg is true, then the counter is reset to zero after this
drhd1d38482008-10-07 23:46:38 +00005214** interface call returns.
5215**
5216** See also: [sqlite3_status()] and [sqlite3_db_status()].
5217*/
drh9f8da322010-03-10 20:06:37 +00005218int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
drhd1d38482008-10-07 23:46:38 +00005219
5220/*
drhd68eee02009-12-11 03:44:18 +00005221** CAPI3REF: Status Parameters for prepared statements
drhd1d38482008-10-07 23:46:38 +00005222**
5223** These preprocessor macros define integer codes that name counter
5224** values associated with the [sqlite3_stmt_status()] interface.
5225** The meanings of the various counters are as follows:
5226**
5227** <dl>
5228** <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
drhd68eee02009-12-11 03:44:18 +00005229** <dd>^This is the number of times that SQLite has stepped forward in
drhd1d38482008-10-07 23:46:38 +00005230** a table as part of a full table scan. Large numbers for this counter
5231** may indicate opportunities for performance improvement through
5232** careful use of indices.</dd>
5233**
5234** <dt>SQLITE_STMTSTATUS_SORT</dt>
drhd68eee02009-12-11 03:44:18 +00005235** <dd>^This is the number of sort operations that have occurred.
drhd1d38482008-10-07 23:46:38 +00005236** A non-zero value in this counter may indicate an opportunity to
5237** improvement performance through careful use of indices.</dd>
5238**
drha21a64d2010-04-06 22:33:55 +00005239** <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
5240** <dd>^This is the number of rows inserted into transient indices that
5241** were created automatically in order to help joins run faster.
5242** A non-zero value in this counter may indicate an opportunity to
5243** improvement performance by adding permanent indices that do not
5244** need to be reinitialized each time the statement is run.</dd>
5245**
drhd1d38482008-10-07 23:46:38 +00005246** </dl>
5247*/
5248#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
5249#define SQLITE_STMTSTATUS_SORT 2
drha21a64d2010-04-06 22:33:55 +00005250#define SQLITE_STMTSTATUS_AUTOINDEX 3
drhd1d38482008-10-07 23:46:38 +00005251
drhed13d982008-01-31 14:43:24 +00005252/*
drh21614742008-11-18 19:18:08 +00005253** CAPI3REF: Custom Page Cache Object
drh21614742008-11-18 19:18:08 +00005254**
danielk1977bc2ca9e2008-11-13 14:28:28 +00005255** The sqlite3_pcache type is opaque. It is implemented by
5256** the pluggable module. The SQLite core has no knowledge of
5257** its size or internal structure and never deals with the
5258** sqlite3_pcache object except by holding and passing pointers
5259** to the object.
drh21614742008-11-18 19:18:08 +00005260**
5261** See [sqlite3_pcache_methods] for additional information.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005262*/
5263typedef struct sqlite3_pcache sqlite3_pcache;
5264
5265/*
drh21614742008-11-18 19:18:08 +00005266** CAPI3REF: Application Defined Page Cache.
drh67fba282009-08-26 00:26:51 +00005267** KEYWORDS: {page cache}
danielk1977bc2ca9e2008-11-13 14:28:28 +00005268**
drhd68eee02009-12-11 03:44:18 +00005269** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can
danielk1977bc2ca9e2008-11-13 14:28:28 +00005270** register an alternative page cache implementation by passing in an
drhdf6473a2009-12-13 22:20:08 +00005271** instance of the sqlite3_pcache_methods structure.)^ The majority of the
shane7c7c3112009-08-17 15:31:23 +00005272** heap memory used by SQLite is used by the page cache to cache data read
danielk1977bc2ca9e2008-11-13 14:28:28 +00005273** from, or ready to be written to, the database file. By implementing a
5274** custom page cache using this API, an application can control more
shane7c7c3112009-08-17 15:31:23 +00005275** precisely the amount of memory consumed by SQLite, the way in which
drh67fba282009-08-26 00:26:51 +00005276** that memory is allocated and released, and the policies used to
danielk1977bc2ca9e2008-11-13 14:28:28 +00005277** determine exactly which parts of a database file are cached and for
5278** how long.
5279**
drhd68eee02009-12-11 03:44:18 +00005280** ^(The contents of the sqlite3_pcache_methods structure are copied to an
drh67fba282009-08-26 00:26:51 +00005281** internal buffer by SQLite within the call to [sqlite3_config]. Hence
5282** the application may discard the parameter after the call to
drhd68eee02009-12-11 03:44:18 +00005283** [sqlite3_config()] returns.)^
danielk1977bc2ca9e2008-11-13 14:28:28 +00005284**
drhd68eee02009-12-11 03:44:18 +00005285** ^The xInit() method is called once for each call to [sqlite3_initialize()]
drh9be37f62009-12-12 23:57:36 +00005286** (usually only once during the lifetime of the process). ^(The xInit()
5287** method is passed a copy of the sqlite3_pcache_methods.pArg value.)^
5288** ^The xInit() method can set up up global structures and/or any mutexes
5289** required by the custom page cache implementation.
shane7c7c3112009-08-17 15:31:23 +00005290**
drhd68eee02009-12-11 03:44:18 +00005291** ^The xShutdown() method is called from within [sqlite3_shutdown()],
shane7c7c3112009-08-17 15:31:23 +00005292** if the application invokes this API. It can be used to clean up
5293** any outstanding resources before process shutdown, if required.
5294**
drhd68eee02009-12-11 03:44:18 +00005295** ^SQLite holds a [SQLITE_MUTEX_RECURSIVE] mutex when it invokes
5296** the xInit method, so the xInit method need not be threadsafe. ^The
shane7c7c3112009-08-17 15:31:23 +00005297** xShutdown method is only called from [sqlite3_shutdown()] so it does
5298** not need to be threadsafe either. All other methods must be threadsafe
5299** in multithreaded applications.
5300**
drhd68eee02009-12-11 03:44:18 +00005301** ^SQLite will never invoke xInit() more than once without an intervening
shane7c7c3112009-08-17 15:31:23 +00005302** call to xShutdown().
danielk1977bc2ca9e2008-11-13 14:28:28 +00005303**
drhd68eee02009-12-11 03:44:18 +00005304** ^The xCreate() method is used to construct a new cache instance. SQLite
drh67fba282009-08-26 00:26:51 +00005305** will typically create one cache instance for each open database file,
drhd68eee02009-12-11 03:44:18 +00005306** though this is not guaranteed. ^The
danielk1977bc2ca9e2008-11-13 14:28:28 +00005307** first parameter, szPage, is the size in bytes of the pages that must
drhd68eee02009-12-11 03:44:18 +00005308** be allocated by the cache. ^szPage will not be a power of two. ^szPage
drh67fba282009-08-26 00:26:51 +00005309** will the page size of the database file that is to be cached plus an
drhd68eee02009-12-11 03:44:18 +00005310** increment (here called "R") of about 100 or 200. ^SQLite will use the
drh67fba282009-08-26 00:26:51 +00005311** extra R bytes on each page to store metadata about the underlying
5312** database page on disk. The value of R depends
5313** on the SQLite version, the target platform, and how SQLite was compiled.
drhd68eee02009-12-11 03:44:18 +00005314** ^R is constant for a particular build of SQLite. ^The second argument to
drh67fba282009-08-26 00:26:51 +00005315** xCreate(), bPurgeable, is true if the cache being created will
5316** be used to cache database pages of a file stored on disk, or
drhd68eee02009-12-11 03:44:18 +00005317** false if it is used for an in-memory database. ^The cache implementation
drh67fba282009-08-26 00:26:51 +00005318** does not have to do anything special based with the value of bPurgeable;
drhd68eee02009-12-11 03:44:18 +00005319** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
drh67fba282009-08-26 00:26:51 +00005320** never invoke xUnpin() except to deliberately delete a page.
drhd68eee02009-12-11 03:44:18 +00005321** ^In other words, a cache created with bPurgeable set to false will
drh67fba282009-08-26 00:26:51 +00005322** never contain any unpinned pages.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005323**
drhd68eee02009-12-11 03:44:18 +00005324** ^(The xCachesize() method may be called at any time by SQLite to set the
danielk1977bc2ca9e2008-11-13 14:28:28 +00005325** suggested maximum cache-size (number of pages stored by) the cache
5326** instance passed as the first argument. This is the value configured using
drh7a98b852009-12-13 23:03:01 +00005327** the SQLite "[PRAGMA cache_size]" command.)^ ^As with the bPurgeable
5328** parameter, the implementation is not required to do anything with this
drh67fba282009-08-26 00:26:51 +00005329** value; it is advisory only.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005330**
drhd68eee02009-12-11 03:44:18 +00005331** ^The xPagecount() method should return the number of pages currently
drh67fba282009-08-26 00:26:51 +00005332** stored in the cache.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005333**
drh7a98b852009-12-13 23:03:01 +00005334** ^The xFetch() method is used to fetch a page and return a pointer to it.
5335** ^A 'page', in this context, is a buffer of szPage bytes aligned at an
5336** 8-byte boundary. ^The page to be fetched is determined by the key. ^The
danielk1977bc2ca9e2008-11-13 14:28:28 +00005337** mimimum key value is 1. After it has been retrieved using xFetch, the page
drh67fba282009-08-26 00:26:51 +00005338** is considered to be "pinned".
danielk1977bc2ca9e2008-11-13 14:28:28 +00005339**
drhd68eee02009-12-11 03:44:18 +00005340** ^If the requested page is already in the page cache, then the page cache
drh67fba282009-08-26 00:26:51 +00005341** implementation must return a pointer to the page buffer with its content
drhd68eee02009-12-11 03:44:18 +00005342** intact. ^(If the requested page is not already in the cache, then the
drh67fba282009-08-26 00:26:51 +00005343** behavior of the cache implementation is determined by the value of the
5344** createFlag parameter passed to xFetch, according to the following table:
danielk1977bc2ca9e2008-11-13 14:28:28 +00005345**
5346** <table border=1 width=85% align=center>
drh67fba282009-08-26 00:26:51 +00005347** <tr><th> createFlag <th> Behaviour when page is not already in cache
5348** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
5349** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
5350** Otherwise return NULL.
5351** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
5352** NULL if allocating a new page is effectively impossible.
drhd68eee02009-12-11 03:44:18 +00005353** </table>)^
danielk1977bc2ca9e2008-11-13 14:28:28 +00005354**
drh67fba282009-08-26 00:26:51 +00005355** SQLite will normally invoke xFetch() with a createFlag of 0 or 1. If
5356** a call to xFetch() with createFlag==1 returns NULL, then SQLite will
5357** attempt to unpin one or more cache pages by spilling the content of
5358** pinned pages to disk and synching the operating system disk cache. After
5359** attempting to unpin pages, the xFetch() method will be invoked again with
5360** a createFlag of 2.
5361**
drhd68eee02009-12-11 03:44:18 +00005362** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
5363** as its second argument. ^(If the third parameter, discard, is non-zero,
danielk1977bc2ca9e2008-11-13 14:28:28 +00005364** then the page should be evicted from the cache. In this case SQLite
5365** assumes that the next time the page is retrieved from the cache using
drhd68eee02009-12-11 03:44:18 +00005366** the xFetch() method, it will be zeroed.)^ ^If the discard parameter is
5367** zero, then the page is considered to be unpinned. ^The cache implementation
drh67fba282009-08-26 00:26:51 +00005368** may choose to evict unpinned pages at any time.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005369**
drhd68eee02009-12-11 03:44:18 +00005370** ^(The cache is not required to perform any reference counting. A single
danielk1977bc2ca9e2008-11-13 14:28:28 +00005371** call to xUnpin() unpins the page regardless of the number of prior calls
drhd68eee02009-12-11 03:44:18 +00005372** to xFetch().)^
danielk1977bc2ca9e2008-11-13 14:28:28 +00005373**
drhd68eee02009-12-11 03:44:18 +00005374** ^The xRekey() method is used to change the key value associated with the
5375** page passed as the second argument from oldKey to newKey. ^If the cache
drhb232c232008-11-19 01:20:26 +00005376** previously contains an entry associated with newKey, it should be
drhd68eee02009-12-11 03:44:18 +00005377** discarded. ^Any prior cache entry associated with newKey is guaranteed not
drhb232c232008-11-19 01:20:26 +00005378** to be pinned.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005379**
drhd68eee02009-12-11 03:44:18 +00005380** ^When SQLite calls the xTruncate() method, the cache must discard all
danielk1977bc2ca9e2008-11-13 14:28:28 +00005381** existing cache entries with page numbers (keys) greater than or equal
drhd68eee02009-12-11 03:44:18 +00005382** to the value of the iLimit parameter passed to xTruncate(). ^If any
danielk1977bc2ca9e2008-11-13 14:28:28 +00005383** of these pages are pinned, they are implicitly unpinned, meaning that
5384** they can be safely discarded.
5385**
drhd68eee02009-12-11 03:44:18 +00005386** ^The xDestroy() method is used to delete a cache allocated by xCreate().
5387** All resources associated with the specified cache should be freed. ^After
drh21614742008-11-18 19:18:08 +00005388** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
danielk1977bc2ca9e2008-11-13 14:28:28 +00005389** handle invalid, and will not use it with any other sqlite3_pcache_methods
5390** functions.
5391*/
5392typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
5393struct sqlite3_pcache_methods {
5394 void *pArg;
5395 int (*xInit)(void*);
5396 void (*xShutdown)(void*);
5397 sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
5398 void (*xCachesize)(sqlite3_pcache*, int nCachesize);
5399 int (*xPagecount)(sqlite3_pcache*);
5400 void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
5401 void (*xUnpin)(sqlite3_pcache*, void*, int discard);
5402 void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
5403 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
5404 void (*xDestroy)(sqlite3_pcache*);
5405};
5406
5407/*
drh27b3b842009-02-03 18:25:13 +00005408** CAPI3REF: Online Backup Object
drh27b3b842009-02-03 18:25:13 +00005409**
5410** The sqlite3_backup object records state information about an ongoing
drhd68eee02009-12-11 03:44:18 +00005411** online backup operation. ^The sqlite3_backup object is created by
drh27b3b842009-02-03 18:25:13 +00005412** a call to [sqlite3_backup_init()] and is destroyed by a call to
5413** [sqlite3_backup_finish()].
drh52224a72009-02-10 13:41:42 +00005414**
5415** See Also: [Using the SQLite Online Backup API]
drh27b3b842009-02-03 18:25:13 +00005416*/
5417typedef struct sqlite3_backup sqlite3_backup;
5418
5419/*
danielk197704103022009-02-03 16:51:24 +00005420** CAPI3REF: Online Backup API.
danielk197704103022009-02-03 16:51:24 +00005421**
drhd68eee02009-12-11 03:44:18 +00005422** The backup API copies the content of one database into another.
5423** It is useful either for creating backups of databases or
danielk197704103022009-02-03 16:51:24 +00005424** for copying in-memory databases to or from persistent files.
5425**
drh52224a72009-02-10 13:41:42 +00005426** See Also: [Using the SQLite Online Backup API]
5427**
drhd68eee02009-12-11 03:44:18 +00005428** ^Exclusive access is required to the destination database for the
5429** duration of the operation. ^However the source database is only
5430** read-locked while it is actually being read; it is not locked
5431** continuously for the entire backup operation. ^Thus, the backup may be
5432** performed on a live source database without preventing other users from
drhdf6473a2009-12-13 22:20:08 +00005433** reading or writing to the source database while the backup is underway.
danielk197704103022009-02-03 16:51:24 +00005434**
drhd68eee02009-12-11 03:44:18 +00005435** ^(To perform a backup operation:
danielk197704103022009-02-03 16:51:24 +00005436** <ol>
drh62b5d2d2009-02-03 18:47:22 +00005437** <li><b>sqlite3_backup_init()</b> is called once to initialize the
5438** backup,
5439** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
danielk197704103022009-02-03 16:51:24 +00005440** the data between the two databases, and finally
drh62b5d2d2009-02-03 18:47:22 +00005441** <li><b>sqlite3_backup_finish()</b> is called to release all resources
danielk197704103022009-02-03 16:51:24 +00005442** associated with the backup operation.
drhd68eee02009-12-11 03:44:18 +00005443** </ol>)^
danielk197704103022009-02-03 16:51:24 +00005444** There should be exactly one call to sqlite3_backup_finish() for each
5445** successful call to sqlite3_backup_init().
5446**
5447** <b>sqlite3_backup_init()</b>
5448**
drhd68eee02009-12-11 03:44:18 +00005449** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
5450** [database connection] associated with the destination database
5451** and the database name, respectively.
5452** ^The database name is "main" for the main database, "temp" for the
5453** temporary database, or the name specified after the AS keyword in
5454** an [ATTACH] statement for an attached database.
5455** ^The S and M arguments passed to
5456** sqlite3_backup_init(D,N,S,M) identify the [database connection]
5457** and database name of the source database, respectively.
5458** ^The source and destination [database connections] (parameters S and D)
5459** must be different or else sqlite3_backup_init(D,N,S,M) will file with
5460** an error.
danielk197704103022009-02-03 16:51:24 +00005461**
drhd68eee02009-12-11 03:44:18 +00005462** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
5463** returned and an error code and error message are store3d in the
5464** destination [database connection] D.
5465** ^The error code and message for the failed call to sqlite3_backup_init()
5466** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
5467** [sqlite3_errmsg16()] functions.
5468** ^A successful call to sqlite3_backup_init() returns a pointer to an
5469** [sqlite3_backup] object.
5470** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
danielk197704103022009-02-03 16:51:24 +00005471** sqlite3_backup_finish() functions to perform the specified backup
5472** operation.
5473**
5474** <b>sqlite3_backup_step()</b>
5475**
drhd68eee02009-12-11 03:44:18 +00005476** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
5477** the source and destination databases specified by [sqlite3_backup] object B.
drh9be37f62009-12-12 23:57:36 +00005478** ^If N is negative, all remaining source pages are copied.
drhd68eee02009-12-11 03:44:18 +00005479** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
5480** are still more pages to be copied, then the function resturns [SQLITE_OK].
5481** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
5482** from source to destination, then it returns [SQLITE_DONE].
5483** ^If an error occurs while running sqlite3_backup_step(B,N),
5484** then an [error code] is returned. ^As well as [SQLITE_OK] and
drh62b5d2d2009-02-03 18:47:22 +00005485** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
5486** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
5487** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
danielk197704103022009-02-03 16:51:24 +00005488**
drh3289c5e2010-05-05 16:23:26 +00005489** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
5490** <ol>
5491** <li> the destination database was opened read-only, or
5492** <li> the destination database is using write-ahead-log journaling
5493** and the destination and source page sizes differ, or
5494** <li> The destination database is an in-memory database and the
5495** destination and source page sizes differ.
5496** </ol>)^
danielk197704103022009-02-03 16:51:24 +00005497**
drhd68eee02009-12-11 03:44:18 +00005498** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
drh62b5d2d2009-02-03 18:47:22 +00005499** the [sqlite3_busy_handler | busy-handler function]
drhd68eee02009-12-11 03:44:18 +00005500** is invoked (if one is specified). ^If the
danielk197704103022009-02-03 16:51:24 +00005501** busy-handler returns non-zero before the lock is available, then
drhd68eee02009-12-11 03:44:18 +00005502** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
5503** sqlite3_backup_step() can be retried later. ^If the source
drh62b5d2d2009-02-03 18:47:22 +00005504** [database connection]
danielk197704103022009-02-03 16:51:24 +00005505** is being used to write to the source database when sqlite3_backup_step()
drhd68eee02009-12-11 03:44:18 +00005506** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
5507** case the call to sqlite3_backup_step() can be retried later on. ^(If
drh62b5d2d2009-02-03 18:47:22 +00005508** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
5509** [SQLITE_READONLY] is returned, then
danielk197704103022009-02-03 16:51:24 +00005510** there is no point in retrying the call to sqlite3_backup_step(). These
drhd68eee02009-12-11 03:44:18 +00005511** errors are considered fatal.)^ The application must accept
danielk197704103022009-02-03 16:51:24 +00005512** that the backup operation has failed and pass the backup operation handle
5513** to the sqlite3_backup_finish() to release associated resources.
5514**
drhd68eee02009-12-11 03:44:18 +00005515** ^The first call to sqlite3_backup_step() obtains an exclusive lock
5516** on the destination file. ^The exclusive lock is not released until either
danielk197704103022009-02-03 16:51:24 +00005517** sqlite3_backup_finish() is called or the backup operation is complete
drhd68eee02009-12-11 03:44:18 +00005518** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
5519** sqlite3_backup_step() obtains a [shared lock] on the source database that
5520** lasts for the duration of the sqlite3_backup_step() call.
5521** ^Because the source database is not locked between calls to
5522** sqlite3_backup_step(), the source database may be modified mid-way
5523** through the backup process. ^If the source database is modified by an
danielk197704103022009-02-03 16:51:24 +00005524** external process or via a database connection other than the one being
drhd68eee02009-12-11 03:44:18 +00005525** used by the backup operation, then the backup will be automatically
5526** restarted by the next call to sqlite3_backup_step(). ^If the source
danielk197704103022009-02-03 16:51:24 +00005527** database is modified by the using the same database connection as is used
drhd68eee02009-12-11 03:44:18 +00005528** by the backup operation, then the backup database is automatically
danielk197704103022009-02-03 16:51:24 +00005529** updated at the same time.
5530**
5531** <b>sqlite3_backup_finish()</b>
5532**
drhd68eee02009-12-11 03:44:18 +00005533** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
5534** application wishes to abandon the backup operation, the application
5535** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
5536** ^The sqlite3_backup_finish() interfaces releases all
5537** resources associated with the [sqlite3_backup] object.
5538** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
5539** active write-transaction on the destination database is rolled back.
5540** The [sqlite3_backup] object is invalid
danielk197704103022009-02-03 16:51:24 +00005541** and may not be used following a call to sqlite3_backup_finish().
5542**
drhd68eee02009-12-11 03:44:18 +00005543** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
5544** sqlite3_backup_step() errors occurred, regardless or whether or not
5545** sqlite3_backup_step() completed.
5546** ^If an out-of-memory condition or IO error occurred during any prior
5547** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
5548** sqlite3_backup_finish() returns the corresponding [error code].
danielk197704103022009-02-03 16:51:24 +00005549**
drhd68eee02009-12-11 03:44:18 +00005550** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
5551** is not a permanent error and does not affect the return value of
danielk197704103022009-02-03 16:51:24 +00005552** sqlite3_backup_finish().
5553**
5554** <b>sqlite3_backup_remaining(), sqlite3_backup_pagecount()</b>
5555**
drhd68eee02009-12-11 03:44:18 +00005556** ^Each call to sqlite3_backup_step() sets two values inside
5557** the [sqlite3_backup] object: the number of pages still to be backed
5558** up and the total number of pages in the source databae file.
5559** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
5560** retrieve these two values, respectively.
danielk197704103022009-02-03 16:51:24 +00005561**
drhd68eee02009-12-11 03:44:18 +00005562** ^The values returned by these functions are only updated by
5563** sqlite3_backup_step(). ^If the source database is modified during a backup
danielk197704103022009-02-03 16:51:24 +00005564** operation, then the values are not updated to account for any extra
5565** pages that need to be updated or the size of the source database file
5566** changing.
5567**
5568** <b>Concurrent Usage of Database Handles</b>
5569**
drhd68eee02009-12-11 03:44:18 +00005570** ^The source [database connection] may be used by the application for other
danielk197704103022009-02-03 16:51:24 +00005571** purposes while a backup operation is underway or being initialized.
drhd68eee02009-12-11 03:44:18 +00005572** ^If SQLite is compiled and configured to support threadsafe database
danielk197704103022009-02-03 16:51:24 +00005573** connections, then the source database connection may be used concurrently
5574** from within other threads.
5575**
drhd68eee02009-12-11 03:44:18 +00005576** However, the application must guarantee that the destination
5577** [database connection] is not passed to any other API (by any thread) after
danielk197704103022009-02-03 16:51:24 +00005578** sqlite3_backup_init() is called and before the corresponding call to
drhd68eee02009-12-11 03:44:18 +00005579** sqlite3_backup_finish(). SQLite does not currently check to see
5580** if the application incorrectly accesses the destination [database connection]
5581** and so no error code is reported, but the operations may malfunction
5582** nevertheless. Use of the destination database connection while a
5583** backup is in progress might also also cause a mutex deadlock.
danielk197704103022009-02-03 16:51:24 +00005584**
drhd68eee02009-12-11 03:44:18 +00005585** If running in [shared cache mode], the application must
danielk197704103022009-02-03 16:51:24 +00005586** guarantee that the shared cache used by the destination database
5587** is not accessed while the backup is running. In practice this means
drhd68eee02009-12-11 03:44:18 +00005588** that the application must guarantee that the disk file being
danielk197704103022009-02-03 16:51:24 +00005589** backed up to is not accessed by any connection within the process,
5590** not just the specific connection that was passed to sqlite3_backup_init().
5591**
drh27b3b842009-02-03 18:25:13 +00005592** The [sqlite3_backup] object itself is partially threadsafe. Multiple
danielk197704103022009-02-03 16:51:24 +00005593** threads may safely make multiple concurrent calls to sqlite3_backup_step().
5594** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
5595** APIs are not strictly speaking threadsafe. If they are invoked at the
5596** same time as another thread is invoking sqlite3_backup_step() it is
5597** possible that they return invalid values.
5598*/
danielk197704103022009-02-03 16:51:24 +00005599sqlite3_backup *sqlite3_backup_init(
5600 sqlite3 *pDest, /* Destination database handle */
5601 const char *zDestName, /* Destination database name */
5602 sqlite3 *pSource, /* Source database handle */
5603 const char *zSourceName /* Source database name */
5604);
5605int sqlite3_backup_step(sqlite3_backup *p, int nPage);
5606int sqlite3_backup_finish(sqlite3_backup *p);
5607int sqlite3_backup_remaining(sqlite3_backup *p);
5608int sqlite3_backup_pagecount(sqlite3_backup *p);
5609
5610/*
danielk1977404ca072009-03-16 13:19:36 +00005611** CAPI3REF: Unlock Notification
danielk1977404ca072009-03-16 13:19:36 +00005612**
drhd68eee02009-12-11 03:44:18 +00005613** ^When running in shared-cache mode, a database operation may fail with
drh89487472009-03-16 13:37:02 +00005614** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
danielk1977404ca072009-03-16 13:19:36 +00005615** individual tables within the shared-cache cannot be obtained. See
5616** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
drhd68eee02009-12-11 03:44:18 +00005617** ^This API may be used to register a callback that SQLite will invoke
danielk1977404ca072009-03-16 13:19:36 +00005618** when the connection currently holding the required lock relinquishes it.
drhd68eee02009-12-11 03:44:18 +00005619** ^This API is only available if the library was compiled with the
drh89487472009-03-16 13:37:02 +00005620** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
danielk1977404ca072009-03-16 13:19:36 +00005621**
5622** See Also: [Using the SQLite Unlock Notification Feature].
5623**
drhd68eee02009-12-11 03:44:18 +00005624** ^Shared-cache locks are released when a database connection concludes
danielk1977404ca072009-03-16 13:19:36 +00005625** its current transaction, either by committing it or rolling it back.
5626**
drhd68eee02009-12-11 03:44:18 +00005627** ^When a connection (known as the blocked connection) fails to obtain a
danielk1977404ca072009-03-16 13:19:36 +00005628** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
5629** identity of the database connection (the blocking connection) that
drhd68eee02009-12-11 03:44:18 +00005630** has locked the required resource is stored internally. ^After an
danielk1977404ca072009-03-16 13:19:36 +00005631** application receives an SQLITE_LOCKED error, it may call the
5632** sqlite3_unlock_notify() method with the blocked connection handle as
5633** the first argument to register for a callback that will be invoked
drhd68eee02009-12-11 03:44:18 +00005634** when the blocking connections current transaction is concluded. ^The
danielk1977404ca072009-03-16 13:19:36 +00005635** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
5636** call that concludes the blocking connections transaction.
5637**
drhd68eee02009-12-11 03:44:18 +00005638** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
danielk1977404ca072009-03-16 13:19:36 +00005639** there is a chance that the blocking connection will have already
5640** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
5641** If this happens, then the specified callback is invoked immediately,
drhd68eee02009-12-11 03:44:18 +00005642** from within the call to sqlite3_unlock_notify().)^
danielk1977404ca072009-03-16 13:19:36 +00005643**
drhd68eee02009-12-11 03:44:18 +00005644** ^If the blocked connection is attempting to obtain a write-lock on a
danielk1977404ca072009-03-16 13:19:36 +00005645** shared-cache table, and more than one other connection currently holds
5646** a read-lock on the same table, then SQLite arbitrarily selects one of
5647** the other connections to use as the blocking connection.
5648**
drhd68eee02009-12-11 03:44:18 +00005649** ^(There may be at most one unlock-notify callback registered by a
danielk1977404ca072009-03-16 13:19:36 +00005650** blocked connection. If sqlite3_unlock_notify() is called when the
5651** blocked connection already has a registered unlock-notify callback,
drh7a98b852009-12-13 23:03:01 +00005652** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
danielk1977404ca072009-03-16 13:19:36 +00005653** called with a NULL pointer as its second argument, then any existing
drhd68eee02009-12-11 03:44:18 +00005654** unlock-notify callback is cancelled. ^The blocked connections
danielk1977404ca072009-03-16 13:19:36 +00005655** unlock-notify callback may also be canceled by closing the blocked
5656** connection using [sqlite3_close()].
5657**
5658** The unlock-notify callback is not reentrant. If an application invokes
5659** any sqlite3_xxx API functions from within an unlock-notify callback, a
5660** crash or deadlock may be the result.
5661**
drhd68eee02009-12-11 03:44:18 +00005662** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
danielk1977404ca072009-03-16 13:19:36 +00005663** returns SQLITE_OK.
5664**
5665** <b>Callback Invocation Details</b>
5666**
5667** When an unlock-notify callback is registered, the application provides a
5668** single void* pointer that is passed to the callback when it is invoked.
5669** However, the signature of the callback function allows SQLite to pass
5670** it an array of void* context pointers. The first argument passed to
5671** an unlock-notify callback is a pointer to an array of void* pointers,
5672** and the second is the number of entries in the array.
5673**
5674** When a blocking connections transaction is concluded, there may be
5675** more than one blocked connection that has registered for an unlock-notify
drhd68eee02009-12-11 03:44:18 +00005676** callback. ^If two or more such blocked connections have specified the
danielk1977404ca072009-03-16 13:19:36 +00005677** same callback function, then instead of invoking the callback function
5678** multiple times, it is invoked once with the set of void* context pointers
5679** specified by the blocked connections bundled together into an array.
5680** This gives the application an opportunity to prioritize any actions
5681** related to the set of unblocked database connections.
5682**
5683** <b>Deadlock Detection</b>
5684**
5685** Assuming that after registering for an unlock-notify callback a
5686** database waits for the callback to be issued before taking any further
5687** action (a reasonable assumption), then using this API may cause the
5688** application to deadlock. For example, if connection X is waiting for
5689** connection Y's transaction to be concluded, and similarly connection
5690** Y is waiting on connection X's transaction, then neither connection
5691** will proceed and the system may remain deadlocked indefinitely.
5692**
5693** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
drhd68eee02009-12-11 03:44:18 +00005694** detection. ^If a given call to sqlite3_unlock_notify() would put the
danielk1977404ca072009-03-16 13:19:36 +00005695** system in a deadlocked state, then SQLITE_LOCKED is returned and no
5696** unlock-notify callback is registered. The system is said to be in
5697** a deadlocked state if connection A has registered for an unlock-notify
5698** callback on the conclusion of connection B's transaction, and connection
5699** B has itself registered for an unlock-notify callback when connection
drhd68eee02009-12-11 03:44:18 +00005700** A's transaction is concluded. ^Indirect deadlock is also detected, so
danielk1977404ca072009-03-16 13:19:36 +00005701** the system is also considered to be deadlocked if connection B has
5702** registered for an unlock-notify callback on the conclusion of connection
drhd68eee02009-12-11 03:44:18 +00005703** C's transaction, where connection C is waiting on connection A. ^Any
danielk1977404ca072009-03-16 13:19:36 +00005704** number of levels of indirection are allowed.
5705**
5706** <b>The "DROP TABLE" Exception</b>
5707**
5708** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
5709** always appropriate to call sqlite3_unlock_notify(). There is however,
5710** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
5711** SQLite checks if there are any currently executing SELECT statements
5712** that belong to the same connection. If there are, SQLITE_LOCKED is
5713** returned. In this case there is no "blocking connection", so invoking
5714** sqlite3_unlock_notify() results in the unlock-notify callback being
5715** invoked immediately. If the application then re-attempts the "DROP TABLE"
5716** or "DROP INDEX" query, an infinite loop might be the result.
5717**
5718** One way around this problem is to check the extended error code returned
drhd68eee02009-12-11 03:44:18 +00005719** by an sqlite3_step() call. ^(If there is a blocking connection, then the
danielk1977404ca072009-03-16 13:19:36 +00005720** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
5721** the special "DROP TABLE/INDEX" case, the extended error code is just
drhd68eee02009-12-11 03:44:18 +00005722** SQLITE_LOCKED.)^
danielk1977404ca072009-03-16 13:19:36 +00005723*/
5724int sqlite3_unlock_notify(
5725 sqlite3 *pBlocked, /* Waiting connection */
5726 void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
5727 void *pNotifyArg /* Argument to pass to xNotify */
5728);
5729
danielk1977ee0484c2009-07-28 16:44:26 +00005730
5731/*
5732** CAPI3REF: String Comparison
danielk1977ee0484c2009-07-28 16:44:26 +00005733**
drhd68eee02009-12-11 03:44:18 +00005734** ^The [sqlite3_strnicmp()] API allows applications and extensions to
danielk1977ee0484c2009-07-28 16:44:26 +00005735** compare the contents of two buffers containing UTF-8 strings in a
5736** case-indendent fashion, using the same definition of case independence
5737** that SQLite uses internally when comparing identifiers.
5738*/
5739int sqlite3_strnicmp(const char *, const char *, int);
5740
danielk1977404ca072009-03-16 13:19:36 +00005741/*
drh3f280702010-02-18 18:45:09 +00005742** CAPI3REF: Error Logging Interface
drh3f280702010-02-18 18:45:09 +00005743**
5744** ^The [sqlite3_log()] interface writes a message into the error log
drh71caabf2010-02-26 15:39:24 +00005745** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
drhbee80652010-02-25 21:27:58 +00005746** ^If logging is enabled, the zFormat string and subsequent arguments are
drhd3d986d2010-03-31 13:57:56 +00005747** used with [sqlite3_snprintf()] to generate the final output string.
drh3f280702010-02-18 18:45:09 +00005748**
5749** The sqlite3_log() interface is intended for use by extensions such as
5750** virtual tables, collating functions, and SQL functions. While there is
5751** nothing to prevent an application from calling sqlite3_log(), doing so
5752** is considered bad form.
drhbee80652010-02-25 21:27:58 +00005753**
5754** The zFormat string must not be NULL.
drh7c0c4602010-03-03 22:25:18 +00005755**
5756** To avoid deadlocks and other threading problems, the sqlite3_log() routine
5757** will not use dynamically allocated memory. The log message is stored in
5758** a fixed-length buffer on the stack. If the log message is longer than
5759** a few hundred characters, it will be truncated to the length of the
5760** buffer.
drh3f280702010-02-18 18:45:09 +00005761*/
drha7564662010-02-22 19:32:31 +00005762void sqlite3_log(int iErrCode, const char *zFormat, ...);
drh3f280702010-02-18 18:45:09 +00005763
5764/*
drh833bf962010-04-28 14:42:19 +00005765** CAPI3REF: Write-Ahead Log Commit Hook
dan8d22a172010-04-19 18:03:51 +00005766**
drh005e19c2010-05-07 13:57:11 +00005767** ^The [sqlite3_wal_hook()] function is used to register a callback that
dan8d22a172010-04-19 18:03:51 +00005768** will be invoked each time a database connection commits data to a
drh005e19c2010-05-07 13:57:11 +00005769** [write-ahead log] (i.e. whenever a transaction is committed in
5770** [journal_mode | journal_mode=WAL mode]).
dan8d22a172010-04-19 18:03:51 +00005771**
drh005e19c2010-05-07 13:57:11 +00005772** ^The callback is invoked by SQLite after the commit has taken place and
dan8d22a172010-04-19 18:03:51 +00005773** the associated write-lock on the database released, so the implementation
drh005e19c2010-05-07 13:57:11 +00005774** may read, write or [checkpoint] the database as required.
dan8d22a172010-04-19 18:03:51 +00005775**
drh005e19c2010-05-07 13:57:11 +00005776** ^The first parameter passed to the callback function when it is invoked
drh833bf962010-04-28 14:42:19 +00005777** is a copy of the third parameter passed to sqlite3_wal_hook() when
drh005e19c2010-05-07 13:57:11 +00005778** registering the callback. ^The second is a copy of the database handle.
5779** ^The third parameter is the name of the database that was written to -
5780** either "main" or the name of an ATTACHed database. ^The fourth parameter
5781** is the number of pages currently in the write-ahead log file,
5782** including those that were just committed.
dan8d22a172010-04-19 18:03:51 +00005783**
drh005e19c2010-05-07 13:57:11 +00005784** The callback function should normally return SQLITE_OK. ^If an error
drh5def0842010-05-05 20:00:25 +00005785** code is returned, that error will propagate back up through the
5786** SQLite code base to cause the statement that provoked the callback
dan982d4c02010-05-15 10:24:46 +00005787** to report an error, though the commit will have still occurred. If the
5788** callback returns SQLITE_ROW or SQLITE_DONE, or if it returns a value
5789** that does not correspond to any valid SQLite error code, the results
5790** are undefined.
dan8d22a172010-04-19 18:03:51 +00005791**
drh005e19c2010-05-07 13:57:11 +00005792** A single database handle may have at most a single write-ahead log callback
5793** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
5794** previously registered write-ahead log callback. Note that the
5795** [sqlite3_wal_autocheckpoint()] interface and the
5796** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
5797** those overwrite any prior [sqlite3_wal_hook()] settings.
dan8d22a172010-04-19 18:03:51 +00005798*/
drh833bf962010-04-28 14:42:19 +00005799void *sqlite3_wal_hook(
dan8d22a172010-04-19 18:03:51 +00005800 sqlite3*,
5801 int(*)(void *,sqlite3*,const char*,int),
5802 void*
5803);
5804
5805/*
dan586b9c82010-05-03 08:04:49 +00005806** CAPI3REF: Configure an auto-checkpoint
drh324e46d2010-05-03 18:51:41 +00005807**
drh005e19c2010-05-07 13:57:11 +00005808** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
drh324e46d2010-05-03 18:51:41 +00005809** [sqlite3_wal_hook()] that causes any database on [database connection] D
drh005e19c2010-05-07 13:57:11 +00005810** to automatically [checkpoint]
drh324e46d2010-05-03 18:51:41 +00005811** after committing a transaction if there are N or
drh005e19c2010-05-07 13:57:11 +00005812** more frames in the [write-ahead log] file. ^Passing zero or
drh324e46d2010-05-03 18:51:41 +00005813** a negative value as the nFrame parameter disables automatic
5814** checkpoints entirely.
5815**
drh005e19c2010-05-07 13:57:11 +00005816** ^The callback registered by this function replaces any existing callback
5817** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
drh324e46d2010-05-03 18:51:41 +00005818** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
5819** configured by this function.
drh005e19c2010-05-07 13:57:11 +00005820**
5821** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
5822** from SQL.
5823**
5824** ^Every new [database connection] defaults to having the auto-checkpoint
5825** enabled with a threshold of 1000 pages. The use of this interface
5826** is only necessary if the default setting is found to be suboptimal
5827** for a particular application.
dan586b9c82010-05-03 08:04:49 +00005828*/
5829int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
5830
5831/*
5832** CAPI3REF: Checkpoint a database
drh324e46d2010-05-03 18:51:41 +00005833**
drh005e19c2010-05-07 13:57:11 +00005834** ^The [sqlite3_wal_checkpoint(D,X)] interface causes database named X
5835** on [database connection] D to be [checkpointed]. ^If X is NULL or an
drh324e46d2010-05-03 18:51:41 +00005836** empty string, then a checkpoint is run on all databases of
drh6a2607a2010-05-07 18:23:24 +00005837** connection D. ^If the database connection D is not in
drh005e19c2010-05-07 13:57:11 +00005838** [WAL | write-ahead log mode] then this interface is a harmless no-op.
5839**
drh6a2607a2010-05-07 18:23:24 +00005840** ^The [wal_checkpoint pragma] can be used to invoke this interface
5841** from SQL. ^The [sqlite3_wal_autocheckpoint()] interface and the
drh005e19c2010-05-07 13:57:11 +00005842** [wal_autocheckpoint pragma] can be used to cause this interface to be
5843** run whenever the WAL reaches a certain size threshold.
dan586b9c82010-05-03 08:04:49 +00005844*/
5845int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
5846
5847/*
drhb37df7b2005-10-13 02:09:49 +00005848** Undo the hack that converts floating point types to integer for
5849** builds on processors without floating point support.
5850*/
5851#ifdef SQLITE_OMIT_FLOATING_POINT
5852# undef double
5853#endif
5854
drh382c0242001-10-06 16:33:02 +00005855#ifdef __cplusplus
5856} /* End of the 'extern "C"' block */
5857#endif
danielk19774adee202004-05-08 08:23:19 +00005858#endif