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1 /*
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2 ** 2001 September 15
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3 **
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4 ** The author disclaims copyright to this source code. In place of
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5 ** a legal notice, here is a blessing:
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6 **
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7 ** May you do good and not evil.
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8 ** May you find forgiveness for yourself and forgive others.
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9 ** May you share freely, never taking more than you give.
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10 **
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11 *************************************************************************
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12 ** This header file defines the interface that the SQLite library
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13 ** presents to client programs. If a C-function, structure, datatype,
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14 ** or constant definition does not appear in this file, then it is
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15 ** not a published API of SQLite, is subject to change without
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16 ** notice, and should not be referenced by programs that use SQLite.
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17 **
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18 ** Some of the definitions that are in this file are marked as
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19 ** "experimental". Experimental interfaces are normally new
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20 ** features recently added to SQLite. We do not anticipate changes
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21 ** to experimental interfaces but reserve the right to make minor changes
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22 ** if experience from use "in the wild" suggest such changes are prudent.
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23 **
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24 ** The official C-language API documentation for SQLite is derived
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25 ** from comments in this file. This file is the authoritative source
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26 ** on how SQLite interfaces are suppose to operate.
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27 **
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28 ** The name of this file under configuration management is "sqlite.h.in".
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29 ** The makefile makes some minor changes to this file (such as inserting
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30 ** the version number) and changes its name to "sqlite3.h" as
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31 ** part of the build process.
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32 */
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33 #ifndef _SQLITE3_H_
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34 #define _SQLITE3_H_
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35 #include <stdarg.h> /* Needed for the definition of va_list */
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36
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37 /*
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38 ** Make sure we can call this stuff from C++.
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39 */
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40 #ifdef __cplusplus
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41 extern "C" {
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42 #endif
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43
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44
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45 /*
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46 ** Add the ability to override 'extern'
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47 */
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48 #ifndef SQLITE_EXTERN
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49 # define SQLITE_EXTERN extern
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50 #endif
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51
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52 #ifndef SQLITE_API
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53 # define SQLITE_API
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54 #endif
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55
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56
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57 /*
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58 ** These no-op macros are used in front of interfaces to mark those
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59 ** interfaces as either deprecated or experimental. New applications
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60 ** should not use deprecated interfaces - they are support for backwards
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61 ** compatibility only. Application writers should be aware that
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62 ** experimental interfaces are subject to change in point releases.
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63 **
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64 ** These macros used to resolve to various kinds of compiler magic that
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65 ** would generate warning messages when they were used. But that
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66 ** compiler magic ended up generating such a flurry of bug reports
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67 ** that we have taken it all out and gone back to using simple
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68 ** noop macros.
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69 */
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70 #define SQLITE_DEPRECATED
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71 #define SQLITE_EXPERIMENTAL
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72
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73 /*
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74 ** Ensure these symbols were not defined by some previous header file.
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75 */
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76 #ifdef SQLITE_VERSION
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77 # undef SQLITE_VERSION
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78 #endif
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79 #ifdef SQLITE_VERSION_NUMBER
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80 # undef SQLITE_VERSION_NUMBER
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81 #endif
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82
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83 /*
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84 ** CAPI3REF: Compile-Time Library Version Numbers
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85 **
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86 ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
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87 ** evaluates to a string literal that is the SQLite version in the
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88 ** format "X.Y.Z" where X is the major version number (always 3 for
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89 ** SQLite3) and Y is the minor version number and Z is the release number.)^
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90 ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
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91 ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
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92 ** numbers used in [SQLITE_VERSION].)^
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93 ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
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94 ** be larger than the release from which it is derived. Either Y will
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95 ** be held constant and Z will be incremented or else Y will be incremented
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96 ** and Z will be reset to zero.
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97 **
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98 ** Since version 3.6.18, SQLite source code has been stored in the
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99 ** <a href="http://www.fossil-scm.org/">Fossil configuration management
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100 ** system</a>. ^The SQLITE_SOURCE_ID macro evalutes to
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101 ** a string which identifies a particular check-in of SQLite
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102 ** within its configuration management system. ^The SQLITE_SOURCE_ID
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103 ** string contains the date and time of the check-in (UTC) and an SHA1
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104 ** hash of the entire source tree.
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105 **
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106 ** See also: [sqlite3_libversion()],
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107 ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
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108 ** [sqlite_version()] and [sqlite_source_id()].
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109 */
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110 #define SQLITE_VERSION "3.7.0.1"
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111 #define SQLITE_VERSION_NUMBER 3007000
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112 #define SQLITE_SOURCE_ID "2010-08-04 12:31:11 042a1abb030a0711386add7eb6e10832cc8b0f57"
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113
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114 /*
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115 ** CAPI3REF: Run-Time Library Version Numbers
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116 ** KEYWORDS: sqlite3_version, sqlite3_sourceid
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117 **
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118 ** These interfaces provide the same information as the [SQLITE_VERSION],
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119 ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
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120 ** but are associated with the library instead of the header file. ^(Cautious
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121 ** programmers might include assert() statements in their application to
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122 ** verify that values returned by these interfaces match the macros in
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123 ** the header, and thus insure that the application is
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124 ** compiled with matching library and header files.
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125 **
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126 ** <blockquote><pre>
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127 ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
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128 ** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
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129 ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
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130 ** </pre></blockquote>)^
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131 **
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132 ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
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133 ** macro. ^The sqlite3_libversion() function returns a pointer to the
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134 ** to the sqlite3_version[] string constant. The sqlite3_libversion()
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135 ** function is provided for use in DLLs since DLL users usually do not have
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136 ** direct access to string constants within the DLL. ^The
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137 ** sqlite3_libversion_number() function returns an integer equal to
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138 ** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns
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139 ** a pointer to a string constant whose value is the same as the
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140 ** [SQLITE_SOURCE_ID] C preprocessor macro.
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141 **
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142 ** See also: [sqlite_version()] and [sqlite_source_id()].
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143 */
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144 SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
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145 SQLITE_API const char *sqlite3_libversion(void);
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146 SQLITE_API const char *sqlite3_sourceid(void);
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147 SQLITE_API int sqlite3_libversion_number(void);
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148
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149 /*
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150 ** CAPI3REF: Run-Time Library Compilation Options Diagnostics
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151 **
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152 ** ^The sqlite3_compileoption_used() function returns 0 or 1
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153 ** indicating whether the specified option was defined at
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154 ** compile time. ^The SQLITE_ prefix may be omitted from the
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155 ** option name passed to sqlite3_compileoption_used().
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156 **
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157 ** ^The sqlite3_compileoption_get() function allows interating
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158 ** over the list of options that were defined at compile time by
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159 ** returning the N-th compile time option string. ^If N is out of range,
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160 ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
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161 ** prefix is omitted from any strings returned by
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162 ** sqlite3_compileoption_get().
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163 **
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164 ** ^Support for the diagnostic functions sqlite3_compileoption_used()
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165 ** and sqlite3_compileoption_get() may be omitted by specifing the
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166 ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
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167 **
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168 ** See also: SQL functions [sqlite_compileoption_used()] and
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169 ** [sqlite_compileoption_get()] and the [compile_options pragma].
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170 */
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171 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
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172 SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
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173 SQLITE_API const char *sqlite3_compileoption_get(int N);
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174 #endif
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175
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176 /*
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177 ** CAPI3REF: Test To See If The Library Is Threadsafe
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178 **
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179 ** ^The sqlite3_threadsafe() function returns zero if and only if
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180 ** SQLite was compiled mutexing code omitted due to the
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181 ** [SQLITE_THREADSAFE] compile-time option being set to 0.
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182 **
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183 ** SQLite can be compiled with or without mutexes. When
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184 ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
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185 ** are enabled and SQLite is threadsafe. When the
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186 ** [SQLITE_THREADSAFE] macro is 0,
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187 ** the mutexes are omitted. Without the mutexes, it is not safe
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188 ** to use SQLite concurrently from more than one thread.
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189 **
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190 ** Enabling mutexes incurs a measurable performance penalty.
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191 ** So if speed is of utmost importance, it makes sense to disable
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192 ** the mutexes. But for maximum safety, mutexes should be enabled.
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193 ** ^The default behavior is for mutexes to be enabled.
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194 **
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195 ** This interface can be used by an application to make sure that the
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196 ** version of SQLite that it is linking against was compiled with
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197 ** the desired setting of the [SQLITE_THREADSAFE] macro.
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198 **
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199 ** This interface only reports on the compile-time mutex setting
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200 ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
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201 ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
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202 ** can be fully or partially disabled using a call to [sqlite3_config()]
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203 ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
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204 ** or [SQLITE_CONFIG_MUTEX]. ^(The return value of the
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205 ** sqlite3_threadsafe() function shows only the compile-time setting of
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206 ** thread safety, not any run-time changes to that setting made by
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207 ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
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208 ** is unchanged by calls to sqlite3_config().)^
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209 **
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210 ** See the [threading mode] documentation for additional information.
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211 */
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212 SQLITE_API int sqlite3_threadsafe(void);
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213
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214 /*
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215 ** CAPI3REF: Database Connection Handle
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216 ** KEYWORDS: {database connection} {database connections}
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217 **
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218 ** Each open SQLite database is represented by a pointer to an instance of
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219 ** the opaque structure named "sqlite3". It is useful to think of an sqlite3
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220 ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
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221 ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
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222 ** is its destructor. There are many other interfaces (such as
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223 ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
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224 ** [sqlite3_busy_timeout()] to name but three) that are methods on an
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225 ** sqlite3 object.
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226 */
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227 typedef struct sqlite3 sqlite3;
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228
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229 /*
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230 ** CAPI3REF: 64-Bit Integer Types
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231 ** KEYWORDS: sqlite_int64 sqlite_uint64
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232 **
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233 ** Because there is no cross-platform way to specify 64-bit integer types
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234 ** SQLite includes typedefs for 64-bit signed and unsigned integers.
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235 **
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236 ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
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237 ** The sqlite_int64 and sqlite_uint64 types are supported for backwards
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238 ** compatibility only.
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239 **
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240 ** ^The sqlite3_int64 and sqlite_int64 types can store integer values
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241 ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
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242 ** sqlite3_uint64 and sqlite_uint64 types can store integer values
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243 ** between 0 and +18446744073709551615 inclusive.
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244 */
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245 #ifdef SQLITE_INT64_TYPE
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246 typedef SQLITE_INT64_TYPE sqlite_int64;
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247 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
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248 #elif defined(_MSC_VER) || defined(__BORLANDC__)
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249 typedef __int64 sqlite_int64;
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250 typedef unsigned __int64 sqlite_uint64;
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251 #else
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252 typedef long long int sqlite_int64;
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253 typedef unsigned long long int sqlite_uint64;
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254 #endif
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255 typedef sqlite_int64 sqlite3_int64;
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256 typedef sqlite_uint64 sqlite3_uint64;
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257
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258 /*
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259 ** If compiling for a processor that lacks floating point support,
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260 ** substitute integer for floating-point.
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261 */
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262 #ifdef SQLITE_OMIT_FLOATING_POINT
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263 # define double sqlite3_int64
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264 #endif
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265
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266 /*
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267 ** CAPI3REF: Closing A Database Connection
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268 **
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269 ** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
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270 ** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
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271 ** successfullly destroyed and all associated resources are deallocated.
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272 **
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273 ** Applications must [sqlite3_finalize | finalize] all [prepared statements]
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274 ** and [sqlite3_blob_close | close] all [BLOB handles] associated with
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275 ** the [sqlite3] object prior to attempting to close the object. ^If
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276 ** sqlite3_close() is called on a [database connection] that still has
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277 ** outstanding [prepared statements] or [BLOB handles], then it returns
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278 ** SQLITE_BUSY.
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279 **
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280 ** ^If [sqlite3_close()] is invoked while a transaction is open,
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281 ** the transaction is automatically rolled back.
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282 **
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283 ** The C parameter to [sqlite3_close(C)] must be either a NULL
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284 ** pointer or an [sqlite3] object pointer obtained
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285 ** from [sqlite3_open()], [sqlite3_open16()], or
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286 ** [sqlite3_open_v2()], and not previously closed.
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287 ** ^Calling sqlite3_close() with a NULL pointer argument is a
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288 ** harmless no-op.
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289 */
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290 SQLITE_API int sqlite3_close(sqlite3 *);
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291
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292 /*
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293 ** The type for a callback function.
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294 ** This is legacy and deprecated. It is included for historical
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295 ** compatibility and is not documented.
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296 */
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297 typedef int (*sqlite3_callback)(void*,int,char**, char**);
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298
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299 /*
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300 ** CAPI3REF: One-Step Query Execution Interface
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301 **
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302 ** The sqlite3_exec() interface is a convenience wrapper around
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303 ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
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304 ** that allows an application to run multiple statements of SQL
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305 ** without having to use a lot of C code.
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306 **
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307 ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
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308 ** semicolon-separate SQL statements passed into its 2nd argument,
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309 ** in the context of the [database connection] passed in as its 1st
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310 ** argument. ^If the callback function of the 3rd argument to
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311 ** sqlite3_exec() is not NULL, then it is invoked for each result row
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312 ** coming out of the evaluated SQL statements. ^The 4th argument to
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313 ** to sqlite3_exec() is relayed through to the 1st argument of each
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314 ** callback invocation. ^If the callback pointer to sqlite3_exec()
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315 ** is NULL, then no callback is ever invoked and result rows are
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316 ** ignored.
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317 **
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318 ** ^If an error occurs while evaluating the SQL statements passed into
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319 ** sqlite3_exec(), then execution of the current statement stops and
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320 ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
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321 ** is not NULL then any error message is written into memory obtained
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322 ** from [sqlite3_malloc()] and passed back through the 5th parameter.
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323 ** To avoid memory leaks, the application should invoke [sqlite3_free()]
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324 ** on error message strings returned through the 5th parameter of
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325 ** of sqlite3_exec() after the error message string is no longer needed.
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326 ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
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327 ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
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328 ** NULL before returning.
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329 **
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330 ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
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331 ** routine returns SQLITE_ABORT without invoking the callback again and
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332 ** without running any subsequent SQL statements.
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333 **
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334 ** ^The 2nd argument to the sqlite3_exec() callback function is the
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335 ** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
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336 ** callback is an array of pointers to strings obtained as if from
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337 ** [sqlite3_column_text()], one for each column. ^If an element of a
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338 ** result row is NULL then the corresponding string pointer for the
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339 ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
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340 ** sqlite3_exec() callback is an array of pointers to strings where each
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341 ** entry represents the name of corresponding result column as obtained
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342 ** from [sqlite3_column_name()].
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343 **
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344 ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
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345 ** to an empty string, or a pointer that contains only whitespace and/or
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346 ** SQL comments, then no SQL statements are evaluated and the database
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347 ** is not changed.
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348 **
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349 ** Restrictions:
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350 **
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351 ** <ul>
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352 ** <li> The application must insure that the 1st parameter to sqlite3_exec()
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353 ** is a valid and open [database connection].
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354 ** <li> The application must not close [database connection] specified by
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355 ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
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356 ** <li> The application must not modify the SQL statement text passed into
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357 ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
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358 ** </ul>
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359 */
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360 SQLITE_API int sqlite3_exec(
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361 sqlite3*, /* An open database */
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362 const char *sql, /* SQL to be evaluated */
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363 int (*callback)(void*,int,char**,char**), /* Callback function */
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364 void *, /* 1st argument to callback */
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365 char **errmsg /* Error msg written here */
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366 );
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367
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368 /*
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369 ** CAPI3REF: Result Codes
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370 ** KEYWORDS: SQLITE_OK {error code} {error codes}
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371 ** KEYWORDS: {result code} {result codes}
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372 **
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373 ** Many SQLite functions return an integer result code from the set shown
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374 ** here in order to indicates success or failure.
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375 **
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376 ** New error codes may be added in future versions of SQLite.
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377 **
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378 ** See also: [SQLITE_IOERR_READ | extended result codes]
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379 */
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380 #define SQLITE_OK 0 /* Successful result */
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381 /* beginning-of-error-codes */
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382 #define SQLITE_ERROR 1 /* SQL error or missing database */
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383 #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
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384 #define SQLITE_PERM 3 /* Access permission denied */
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385 #define SQLITE_ABORT 4 /* Callback routine requested an abort */
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386 #define SQLITE_BUSY 5 /* The database file is locked */
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387 #define SQLITE_LOCKED 6 /* A table in the database is locked */
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388 #define SQLITE_NOMEM 7 /* A malloc() failed */
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389 #define SQLITE_READONLY 8 /* Attempt to write a readonly database */
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390 #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
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391 #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
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392 #define SQLITE_CORRUPT 11 /* The database disk image is malformed */
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393 #define SQLITE_NOTFOUND 12 /* NOT USED. Table or record not found */
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394 #define SQLITE_FULL 13 /* Insertion failed because database is full */
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395 #define SQLITE_CANTOPEN 14 /* Unable to open the database file */
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396 #define SQLITE_PROTOCOL 15 /* Database lock protocol error */
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397 #define SQLITE_EMPTY 16 /* Database is empty */
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398 #define SQLITE_SCHEMA 17 /* The database schema changed */
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399 #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
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400 #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
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401 #define SQLITE_MISMATCH 20 /* Data type mismatch */
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402 #define SQLITE_MISUSE 21 /* Library used incorrectly */
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403 #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
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404 #define SQLITE_AUTH 23 /* Authorization denied */
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405 #define SQLITE_FORMAT 24 /* Auxiliary database format error */
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406 #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
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407 #define SQLITE_NOTADB 26 /* File opened that is not a database file */
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408 #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
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409 #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
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410 /* end-of-error-codes */
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411
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412 /*
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413 ** CAPI3REF: Extended Result Codes
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414 ** KEYWORDS: {extended error code} {extended error codes}
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415 ** KEYWORDS: {extended result code} {extended result codes}
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416 **
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417 ** In its default configuration, SQLite API routines return one of 26 integer
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418 ** [SQLITE_OK | result codes]. However, experience has shown that many of
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419 ** these result codes are too coarse-grained. They do not provide as
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420 ** much information about problems as programmers might like. In an effort to
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421 ** address this, newer versions of SQLite (version 3.3.8 and later) include
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422 ** support for additional result codes that provide more detailed information
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423 ** about errors. The extended result codes are enabled or disabled
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424 ** on a per database connection basis using the
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425 ** [sqlite3_extended_result_codes()] API.
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426 **
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427 ** Some of the available extended result codes are listed here.
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428 ** One may expect the number of extended result codes will be expand
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429 ** over time. Software that uses extended result codes should expect
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430 ** to see new result codes in future releases of SQLite.
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431 **
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432 ** The SQLITE_OK result code will never be extended. It will always
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433 ** be exactly zero.
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434 */
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435 #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
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436 #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
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437 #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
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438 #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
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439 #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
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440 #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
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441 #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
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442 #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
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443 #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
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444 #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
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445 #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
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446 #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
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447 #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
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448 #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
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449 #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
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450 #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
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451 #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
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452 #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
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453 #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
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454 #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
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455 #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
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456 #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
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457 #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
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458
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459 /*
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460 ** CAPI3REF: Flags For File Open Operations
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461 **
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|
462 ** These bit values are intended for use in the
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463 ** 3rd parameter to the [sqlite3_open_v2()] interface and
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|
464 ** in the 4th parameter to the xOpen method of the
|
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465 ** [sqlite3_vfs] object.
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466 */
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467 #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
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|
468 #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
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|
|
469 #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
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|
470 #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
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|
|
471 #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
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|
|
472 #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
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|
|
473 #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
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|
|
474 #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
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|
|
475 #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
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|
|
476 #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
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|
|
477 #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
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|
|
478 #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
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|
|
479 #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
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|
|
480 #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
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|
|
481 #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
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|
|
482 #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
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|
|
483 #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
|
|
|
484 #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
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|
|
485
|
|
|
486 /*
|
|
|
487 ** CAPI3REF: Device Characteristics
|
|
|
488 **
|
|
|
489 ** The xDeviceCharacteristics method of the [sqlite3_io_methods]
|
|
|
490 ** object returns an integer which is a vector of the these
|
|
|
491 ** bit values expressing I/O characteristics of the mass storage
|
|
|
492 ** device that holds the file that the [sqlite3_io_methods]
|
|
|
493 ** refers to.
|
|
|
494 **
|
|
|
495 ** The SQLITE_IOCAP_ATOMIC property means that all writes of
|
|
|
496 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
|
|
|
497 ** mean that writes of blocks that are nnn bytes in size and
|
|
|
498 ** are aligned to an address which is an integer multiple of
|
|
|
499 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
|
|
|
500 ** that when data is appended to a file, the data is appended
|
|
|
501 ** first then the size of the file is extended, never the other
|
|
|
502 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
|
|
|
503 ** information is written to disk in the same order as calls
|
|
|
504 ** to xWrite().
|
|
|
505 */
|
|
|
506 #define SQLITE_IOCAP_ATOMIC 0x00000001
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|
|
507 #define SQLITE_IOCAP_ATOMIC512 0x00000002
|
|
|
508 #define SQLITE_IOCAP_ATOMIC1K 0x00000004
|
|
|
509 #define SQLITE_IOCAP_ATOMIC2K 0x00000008
|
|
|
510 #define SQLITE_IOCAP_ATOMIC4K 0x00000010
|
|
|
511 #define SQLITE_IOCAP_ATOMIC8K 0x00000020
|
|
|
512 #define SQLITE_IOCAP_ATOMIC16K 0x00000040
|
|
|
513 #define SQLITE_IOCAP_ATOMIC32K 0x00000080
|
|
|
514 #define SQLITE_IOCAP_ATOMIC64K 0x00000100
|
|
|
515 #define SQLITE_IOCAP_SAFE_APPEND 0x00000200
|
|
|
516 #define SQLITE_IOCAP_SEQUENTIAL 0x00000400
|
|
|
517 #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
|
|
|
518
|
|
|
519 /*
|
|
|
520 ** CAPI3REF: File Locking Levels
|
|
|
521 **
|
|
|
522 ** SQLite uses one of these integer values as the second
|
|
|
523 ** argument to calls it makes to the xLock() and xUnlock() methods
|
|
|
524 ** of an [sqlite3_io_methods] object.
|
|
|
525 */
|
|
|
526 #define SQLITE_LOCK_NONE 0
|
|
|
527 #define SQLITE_LOCK_SHARED 1
|
|
|
528 #define SQLITE_LOCK_RESERVED 2
|
|
|
529 #define SQLITE_LOCK_PENDING 3
|
|
|
530 #define SQLITE_LOCK_EXCLUSIVE 4
|
|
|
531
|
|
|
532 /*
|
|
|
533 ** CAPI3REF: Synchronization Type Flags
|
|
|
534 **
|
|
|
535 ** When SQLite invokes the xSync() method of an
|
|
|
536 ** [sqlite3_io_methods] object it uses a combination of
|
|
|
537 ** these integer values as the second argument.
|
|
|
538 **
|
|
|
539 ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
|
|
|
540 ** sync operation only needs to flush data to mass storage. Inode
|
|
|
541 ** information need not be flushed. If the lower four bits of the flag
|
|
|
542 ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
|
|
|
543 ** If the lower four bits equal SQLITE_SYNC_FULL, that means
|
|
|
544 ** to use Mac OS X style fullsync instead of fsync().
|
|
|
545 */
|
|
|
546 #define SQLITE_SYNC_NORMAL 0x00002
|
|
|
547 #define SQLITE_SYNC_FULL 0x00003
|
|
|
548 #define SQLITE_SYNC_DATAONLY 0x00010
|
|
|
549
|
|
|
550 /*
|
|
|
551 ** CAPI3REF: OS Interface Open File Handle
|
|
|
552 **
|
|
|
553 ** An [sqlite3_file] object represents an open file in the
|
|
|
554 ** [sqlite3_vfs | OS interface layer]. Individual OS interface
|
|
|
555 ** implementations will
|
|
|
556 ** want to subclass this object by appending additional fields
|
|
|
557 ** for their own use. The pMethods entry is a pointer to an
|
|
|
558 ** [sqlite3_io_methods] object that defines methods for performing
|
|
|
559 ** I/O operations on the open file.
|
|
|
560 */
|
|
|
561 typedef struct sqlite3_file sqlite3_file;
|
|
|
562 struct sqlite3_file {
|
|
|
563 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
|
|
|
564 };
|
|
|
565
|
|
|
566 /*
|
|
|
567 ** CAPI3REF: OS Interface File Virtual Methods Object
|
|
|
568 **
|
|
|
569 ** Every file opened by the [sqlite3_vfs] xOpen method populates an
|
|
|
570 ** [sqlite3_file] object (or, more commonly, a subclass of the
|
|
|
571 ** [sqlite3_file] object) with a pointer to an instance of this object.
|
|
|
572 ** This object defines the methods used to perform various operations
|
|
|
573 ** against the open file represented by the [sqlite3_file] object.
|
|
|
574 **
|
|
|
575 ** If the xOpen method sets the sqlite3_file.pMethods element
|
|
|
576 ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
|
|
|
577 ** may be invoked even if the xOpen reported that it failed. The
|
|
|
578 ** only way to prevent a call to xClose following a failed xOpen
|
|
|
579 ** is for the xOpen to set the sqlite3_file.pMethods element to NULL.
|
|
|
580 **
|
|
|
581 ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
|
|
|
582 ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
|
|
|
583 ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
|
|
|
584 ** flag may be ORed in to indicate that only the data of the file
|
|
|
585 ** and not its inode needs to be synced.
|
|
|
586 **
|
|
|
587 ** The integer values to xLock() and xUnlock() are one of
|
|
|
588 ** <ul>
|
|
|
589 ** <li> [SQLITE_LOCK_NONE],
|
|
|
590 ** <li> [SQLITE_LOCK_SHARED],
|
|
|
591 ** <li> [SQLITE_LOCK_RESERVED],
|
|
|
592 ** <li> [SQLITE_LOCK_PENDING], or
|
|
|
593 ** <li> [SQLITE_LOCK_EXCLUSIVE].
|
|
|
594 ** </ul>
|
|
|
595 ** xLock() increases the lock. xUnlock() decreases the lock.
|
|
|
596 ** The xCheckReservedLock() method checks whether any database connection,
|
|
|
597 ** either in this process or in some other process, is holding a RESERVED,
|
|
|
598 ** PENDING, or EXCLUSIVE lock on the file. It returns true
|
|
|
599 ** if such a lock exists and false otherwise.
|
|
|
600 **
|
|
|
601 ** The xFileControl() method is a generic interface that allows custom
|
|
|
602 ** VFS implementations to directly control an open file using the
|
|
|
603 ** [sqlite3_file_control()] interface. The second "op" argument is an
|
|
|
604 ** integer opcode. The third argument is a generic pointer intended to
|
|
|
605 ** point to a structure that may contain arguments or space in which to
|
|
|
606 ** write return values. Potential uses for xFileControl() might be
|
|
|
607 ** functions to enable blocking locks with timeouts, to change the
|
|
|
608 ** locking strategy (for example to use dot-file locks), to inquire
|
|
|
609 ** about the status of a lock, or to break stale locks. The SQLite
|
|
|
610 ** core reserves all opcodes less than 100 for its own use.
|
|
|
611 ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
|
|
|
612 ** Applications that define a custom xFileControl method should use opcodes
|
|
|
613 ** greater than 100 to avoid conflicts.
|
|
|
614 **
|
|
|
615 ** The xSectorSize() method returns the sector size of the
|
|
|
616 ** device that underlies the file. The sector size is the
|
|
|
617 ** minimum write that can be performed without disturbing
|
|
|
618 ** other bytes in the file. The xDeviceCharacteristics()
|
|
|
619 ** method returns a bit vector describing behaviors of the
|
|
|
620 ** underlying device:
|
|
|
621 **
|
|
|
622 ** <ul>
|
|
|
623 ** <li> [SQLITE_IOCAP_ATOMIC]
|
|
|
624 ** <li> [SQLITE_IOCAP_ATOMIC512]
|
|
|
625 ** <li> [SQLITE_IOCAP_ATOMIC1K]
|
|
|
626 ** <li> [SQLITE_IOCAP_ATOMIC2K]
|
|
|
627 ** <li> [SQLITE_IOCAP_ATOMIC4K]
|
|
|
628 ** <li> [SQLITE_IOCAP_ATOMIC8K]
|
|
|
629 ** <li> [SQLITE_IOCAP_ATOMIC16K]
|
|
|
630 ** <li> [SQLITE_IOCAP_ATOMIC32K]
|
|
|
631 ** <li> [SQLITE_IOCAP_ATOMIC64K]
|
|
|
632 ** <li> [SQLITE_IOCAP_SAFE_APPEND]
|
|
|
633 ** <li> [SQLITE_IOCAP_SEQUENTIAL]
|
|
|
634 ** </ul>
|
|
|
635 **
|
|
|
636 ** The SQLITE_IOCAP_ATOMIC property means that all writes of
|
|
|
637 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
|
|
|
638 ** mean that writes of blocks that are nnn bytes in size and
|
|
|
639 ** are aligned to an address which is an integer multiple of
|
|
|
640 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
|
|
|
641 ** that when data is appended to a file, the data is appended
|
|
|
642 ** first then the size of the file is extended, never the other
|
|
|
643 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
|
|
|
644 ** information is written to disk in the same order as calls
|
|
|
645 ** to xWrite().
|
|
|
646 **
|
|
|
647 ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
|
|
|
648 ** in the unread portions of the buffer with zeros. A VFS that
|
|
|
649 ** fails to zero-fill short reads might seem to work. However,
|
|
|
650 ** failure to zero-fill short reads will eventually lead to
|
|
|
651 ** database corruption.
|
|
|
652 */
|
|
|
653 typedef struct sqlite3_io_methods sqlite3_io_methods;
|
|
|
654 struct sqlite3_io_methods {
|
|
|
655 int iVersion;
|
|
|
656 int (*xClose)(sqlite3_file*);
|
|
|
657 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
|
|
|
658 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
|
|
|
659 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
|
|
|
660 int (*xSync)(sqlite3_file*, int flags);
|
|
|
661 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
|
|
|
662 int (*xLock)(sqlite3_file*, int);
|
|
|
663 int (*xUnlock)(sqlite3_file*, int);
|
|
|
664 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
|
|
|
665 int (*xFileControl)(sqlite3_file*, int op, void *pArg);
|
|
|
666 int (*xSectorSize)(sqlite3_file*);
|
|
|
667 int (*xDeviceCharacteristics)(sqlite3_file*);
|
|
|
668 /* Methods above are valid for version 1 */
|
|
|
669 int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
|
|
|
670 int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
|
|
|
671 void (*xShmBarrier)(sqlite3_file*);
|
|
|
672 int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
|
|
|
673 /* Methods above are valid for version 2 */
|
|
|
674 /* Additional methods may be added in future releases */
|
|
|
675 };
|
|
|
676
|
|
|
677 /*
|
|
|
678 ** CAPI3REF: Standard File Control Opcodes
|
|
|
679 **
|
|
|
680 ** These integer constants are opcodes for the xFileControl method
|
|
|
681 ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
|
|
|
682 ** interface.
|
|
|
683 **
|
|
|
684 ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
|
|
|
685 ** opcode causes the xFileControl method to write the current state of
|
|
|
686 ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
|
|
|
687 ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
|
|
|
688 ** into an integer that the pArg argument points to. This capability
|
|
|
689 ** is used during testing and only needs to be supported when SQLITE_TEST
|
|
|
690 ** is defined.
|
|
|
691 **
|
|
|
692 ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
|
|
|
693 ** layer a hint of how large the database file will grow to be during the
|
|
|
694 ** current transaction. This hint is not guaranteed to be accurate but it
|
|
|
695 ** is often close. The underlying VFS might choose to preallocate database
|
|
|
696 ** file space based on this hint in order to help writes to the database
|
|
|
697 ** file run faster.
|
|
|
698 */
|
|
|
699 #define SQLITE_FCNTL_LOCKSTATE 1
|
|
|
700 #define SQLITE_GET_LOCKPROXYFILE 2
|
|
|
701 #define SQLITE_SET_LOCKPROXYFILE 3
|
|
|
702 #define SQLITE_LAST_ERRNO 4
|
|
|
703 #define SQLITE_FCNTL_SIZE_HINT 5
|
|
|
704
|
|
|
705 /*
|
|
|
706 ** CAPI3REF: Mutex Handle
|
|
|
707 **
|
|
|
708 ** The mutex module within SQLite defines [sqlite3_mutex] to be an
|
|
|
709 ** abstract type for a mutex object. The SQLite core never looks
|
|
|
710 ** at the internal representation of an [sqlite3_mutex]. It only
|
|
|
711 ** deals with pointers to the [sqlite3_mutex] object.
|
|
|
712 **
|
|
|
713 ** Mutexes are created using [sqlite3_mutex_alloc()].
|
|
|
714 */
|
|
|
715 typedef struct sqlite3_mutex sqlite3_mutex;
|
|
|
716
|
|
|
717 /*
|
|
|
718 ** CAPI3REF: OS Interface Object
|
|
|
719 **
|
|
|
720 ** An instance of the sqlite3_vfs object defines the interface between
|
|
|
721 ** the SQLite core and the underlying operating system. The "vfs"
|
|
|
722 ** in the name of the object stands for "virtual file system".
|
|
|
723 **
|
|
|
724 ** The value of the iVersion field is initially 1 but may be larger in
|
|
|
725 ** future versions of SQLite. Additional fields may be appended to this
|
|
|
726 ** object when the iVersion value is increased. Note that the structure
|
|
|
727 ** of the sqlite3_vfs object changes in the transaction between
|
|
|
728 ** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
|
|
|
729 ** modified.
|
|
|
730 **
|
|
|
731 ** The szOsFile field is the size of the subclassed [sqlite3_file]
|
|
|
732 ** structure used by this VFS. mxPathname is the maximum length of
|
|
|
733 ** a pathname in this VFS.
|
|
|
734 **
|
|
|
735 ** Registered sqlite3_vfs objects are kept on a linked list formed by
|
|
|
736 ** the pNext pointer. The [sqlite3_vfs_register()]
|
|
|
737 ** and [sqlite3_vfs_unregister()] interfaces manage this list
|
|
|
738 ** in a thread-safe way. The [sqlite3_vfs_find()] interface
|
|
|
739 ** searches the list. Neither the application code nor the VFS
|
|
|
740 ** implementation should use the pNext pointer.
|
|
|
741 **
|
|
|
742 ** The pNext field is the only field in the sqlite3_vfs
|
|
|
743 ** structure that SQLite will ever modify. SQLite will only access
|
|
|
744 ** or modify this field while holding a particular static mutex.
|
|
|
745 ** The application should never modify anything within the sqlite3_vfs
|
|
|
746 ** object once the object has been registered.
|
|
|
747 **
|
|
|
748 ** The zName field holds the name of the VFS module. The name must
|
|
|
749 ** be unique across all VFS modules.
|
|
|
750 **
|
|
|
751 ** SQLite will guarantee that the zFilename parameter to xOpen
|
|
|
752 ** is either a NULL pointer or string obtained
|
|
|
753 ** from xFullPathname(). SQLite further guarantees that
|
|
|
754 ** the string will be valid and unchanged until xClose() is
|
|
|
755 ** called. Because of the previous sentence,
|
|
|
756 ** the [sqlite3_file] can safely store a pointer to the
|
|
|
757 ** filename if it needs to remember the filename for some reason.
|
|
|
758 ** If the zFilename parameter is xOpen is a NULL pointer then xOpen
|
|
|
759 ** must invent its own temporary name for the file. Whenever the
|
|
|
760 ** xFilename parameter is NULL it will also be the case that the
|
|
|
761 ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
|
|
|
762 **
|
|
|
763 ** The flags argument to xOpen() includes all bits set in
|
|
|
764 ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
|
|
|
765 ** or [sqlite3_open16()] is used, then flags includes at least
|
|
|
766 ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
|
|
|
767 ** If xOpen() opens a file read-only then it sets *pOutFlags to
|
|
|
768 ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
|
|
|
769 **
|
|
|
770 ** SQLite will also add one of the following flags to the xOpen()
|
|
|
771 ** call, depending on the object being opened:
|
|
|
772 **
|
|
|
773 ** <ul>
|
|
|
774 ** <li> [SQLITE_OPEN_MAIN_DB]
|
|
|
775 ** <li> [SQLITE_OPEN_MAIN_JOURNAL]
|
|
|
776 ** <li> [SQLITE_OPEN_TEMP_DB]
|
|
|
777 ** <li> [SQLITE_OPEN_TEMP_JOURNAL]
|
|
|
778 ** <li> [SQLITE_OPEN_TRANSIENT_DB]
|
|
|
779 ** <li> [SQLITE_OPEN_SUBJOURNAL]
|
|
|
780 ** <li> [SQLITE_OPEN_MASTER_JOURNAL]
|
|
|
781 ** </ul>
|
|
|
782 **
|
|
|
783 ** The file I/O implementation can use the object type flags to
|
|
|
784 ** change the way it deals with files. For example, an application
|
|
|
785 ** that does not care about crash recovery or rollback might make
|
|
|
786 ** the open of a journal file a no-op. Writes to this journal would
|
|
|
787 ** also be no-ops, and any attempt to read the journal would return
|
|
|
788 ** SQLITE_IOERR. Or the implementation might recognize that a database
|
|
|
789 ** file will be doing page-aligned sector reads and writes in a random
|
|
|
790 ** order and set up its I/O subsystem accordingly.
|
|
|
791 **
|
|
|
792 ** SQLite might also add one of the following flags to the xOpen method:
|
|
|
793 **
|
|
|
794 ** <ul>
|
|
|
795 ** <li> [SQLITE_OPEN_DELETEONCLOSE]
|
|
|
796 ** <li> [SQLITE_OPEN_EXCLUSIVE]
|
|
|
797 ** </ul>
|
|
|
798 **
|
|
|
799 ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
|
|
|
800 ** deleted when it is closed. The [SQLITE_OPEN_DELETEONCLOSE]
|
|
|
801 ** will be set for TEMP databases, journals and for subjournals.
|
|
|
802 **
|
|
|
803 ** The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
|
|
|
804 ** with the [SQLITE_OPEN_CREATE] flag, which are both directly
|
|
|
805 ** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
|
|
|
806 ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
|
|
|
807 ** SQLITE_OPEN_CREATE, is used to indicate that file should always
|
|
|
808 ** be created, and that it is an error if it already exists.
|
|
|
809 ** It is <i>not</i> used to indicate the file should be opened
|
|
|
810 ** for exclusive access.
|
|
|
811 **
|
|
|
812 ** At least szOsFile bytes of memory are allocated by SQLite
|
|
|
813 ** to hold the [sqlite3_file] structure passed as the third
|
|
|
814 ** argument to xOpen. The xOpen method does not have to
|
|
|
815 ** allocate the structure; it should just fill it in. Note that
|
|
|
816 ** the xOpen method must set the sqlite3_file.pMethods to either
|
|
|
817 ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
|
|
|
818 ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
|
|
|
819 ** element will be valid after xOpen returns regardless of the success
|
|
|
820 ** or failure of the xOpen call.
|
|
|
821 **
|
|
|
822 ** The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
|
|
|
823 ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
|
|
|
824 ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
|
|
|
825 ** to test whether a file is at least readable. The file can be a
|
|
|
826 ** directory.
|
|
|
827 **
|
|
|
828 ** SQLite will always allocate at least mxPathname+1 bytes for the
|
|
|
829 ** output buffer xFullPathname. The exact size of the output buffer
|
|
|
830 ** is also passed as a parameter to both methods. If the output buffer
|
|
|
831 ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
|
|
|
832 ** handled as a fatal error by SQLite, vfs implementations should endeavor
|
|
|
833 ** to prevent this by setting mxPathname to a sufficiently large value.
|
|
|
834 **
|
|
|
835 ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
|
|
|
836 ** interfaces are not strictly a part of the filesystem, but they are
|
|
|
837 ** included in the VFS structure for completeness.
|
|
|
838 ** The xRandomness() function attempts to return nBytes bytes
|
|
|
839 ** of good-quality randomness into zOut. The return value is
|
|
|
840 ** the actual number of bytes of randomness obtained.
|
|
|
841 ** The xSleep() method causes the calling thread to sleep for at
|
|
|
842 ** least the number of microseconds given. The xCurrentTime()
|
|
|
843 ** method returns a Julian Day Number for the current date and time as
|
|
|
844 ** a floating point value.
|
|
|
845 ** The xCurrentTimeInt64() method returns, as an integer, the Julian
|
|
|
846 ** Day Number multipled by 86400000 (the number of milliseconds in
|
|
|
847 ** a 24-hour day).
|
|
|
848 ** ^SQLite will use the xCurrentTimeInt64() method to get the current
|
|
|
849 ** date and time if that method is available (if iVersion is 2 or
|
|
|
850 ** greater and the function pointer is not NULL) and will fall back
|
|
|
851 ** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
|
|
|
852 */
|
|
|
853 typedef struct sqlite3_vfs sqlite3_vfs;
|
|
|
854 struct sqlite3_vfs {
|
|
|
855 int iVersion; /* Structure version number (currently 2) */
|
|
|
856 int szOsFile; /* Size of subclassed sqlite3_file */
|
|
|
857 int mxPathname; /* Maximum file pathname length */
|
|
|
858 sqlite3_vfs *pNext; /* Next registered VFS */
|
|
|
859 const char *zName; /* Name of this virtual file system */
|
|
|
860 void *pAppData; /* Pointer to application-specific data */
|
|
|
861 int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
|
|
|
862 int flags, int *pOutFlags);
|
|
|
863 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
|
|
|
864 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
|
|
|
865 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
|
|
|
866 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
|
|
|
867 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
|
|
|
868 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
|
|
|
869 void (*xDlClose)(sqlite3_vfs*, void*);
|
|
|
870 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
|
|
|
871 int (*xSleep)(sqlite3_vfs*, int microseconds);
|
|
|
872 int (*xCurrentTime)(sqlite3_vfs*, double*);
|
|
|
873 int (*xGetLastError)(sqlite3_vfs*, int, char *);
|
|
|
874 /*
|
|
|
875 ** The methods above are in version 1 of the sqlite_vfs object
|
|
|
876 ** definition. Those that follow are added in version 2 or later
|
|
|
877 */
|
|
|
878 int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
|
|
|
879 /*
|
|
|
880 ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
|
|
|
881 ** New fields may be appended in figure versions. The iVersion
|
|
|
882 ** value will increment whenever this happens.
|
|
|
883 */
|
|
|
884 };
|
|
|
885
|
|
|
886 /*
|
|
|
887 ** CAPI3REF: Flags for the xAccess VFS method
|
|
|
888 **
|
|
|
889 ** These integer constants can be used as the third parameter to
|
|
|
890 ** the xAccess method of an [sqlite3_vfs] object. They determine
|
|
|
891 ** what kind of permissions the xAccess method is looking for.
|
|
|
892 ** With SQLITE_ACCESS_EXISTS, the xAccess method
|
|
|
893 ** simply checks whether the file exists.
|
|
|
894 ** With SQLITE_ACCESS_READWRITE, the xAccess method
|
|
|
895 ** checks whether the named directory is both readable and writable
|
|
|
896 ** (in other words, if files can be added, removed, and renamed within
|
|
|
897 ** the directory).
|
|
|
898 ** The SQLITE_ACCESS_READWRITE constant is currently used only by the
|
|
|
899 ** [temp_store_directory pragma], though this could change in a future
|
|
|
900 ** release of SQLite.
|
|
|
901 ** With SQLITE_ACCESS_READ, the xAccess method
|
|
|
902 ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
|
|
|
903 ** currently unused, though it might be used in a future release of
|
|
|
904 ** SQLite.
|
|
|
905 */
|
|
|
906 #define SQLITE_ACCESS_EXISTS 0
|
|
|
907 #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
|
|
|
908 #define SQLITE_ACCESS_READ 2 /* Unused */
|
|
|
909
|
|
|
910 /*
|
|
|
911 ** CAPI3REF: Flags for the xShmLock VFS method
|
|
|
912 **
|
|
|
913 ** These integer constants define the various locking operations
|
|
|
914 ** allowed by the xShmLock method of [sqlite3_io_methods]. The
|
|
|
915 ** following are the only legal combinations of flags to the
|
|
|
916 ** xShmLock method:
|
|
|
917 **
|
|
|
918 ** <ul>
|
|
|
919 ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
|
|
|
920 ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
|
|
|
921 ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
|
|
|
922 ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
|
|
|
923 ** </ul>
|
|
|
924 **
|
|
|
925 ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
|
|
|
926 ** was given no the corresponding lock.
|
|
|
927 **
|
|
|
928 ** The xShmLock method can transition between unlocked and SHARED or
|
|
|
929 ** between unlocked and EXCLUSIVE. It cannot transition between SHARED
|
|
|
930 ** and EXCLUSIVE.
|
|
|
931 */
|
|
|
932 #define SQLITE_SHM_UNLOCK 1
|
|
|
933 #define SQLITE_SHM_LOCK 2
|
|
|
934 #define SQLITE_SHM_SHARED 4
|
|
|
935 #define SQLITE_SHM_EXCLUSIVE 8
|
|
|
936
|
|
|
937 /*
|
|
|
938 ** CAPI3REF: Maximum xShmLock index
|
|
|
939 **
|
|
|
940 ** The xShmLock method on [sqlite3_io_methods] may use values
|
|
|
941 ** between 0 and this upper bound as its "offset" argument.
|
|
|
942 ** The SQLite core will never attempt to acquire or release a
|
|
|
943 ** lock outside of this range
|
|
|
944 */
|
|
|
945 #define SQLITE_SHM_NLOCK 8
|
|
|
946
|
|
|
947
|
|
|
948 /*
|
|
|
949 ** CAPI3REF: Initialize The SQLite Library
|
|
|
950 **
|
|
|
951 ** ^The sqlite3_initialize() routine initializes the
|
|
|
952 ** SQLite library. ^The sqlite3_shutdown() routine
|
|
|
953 ** deallocates any resources that were allocated by sqlite3_initialize().
|
|
|
954 ** These routines are designed to aid in process initialization and
|
|
|
955 ** shutdown on embedded systems. Workstation applications using
|
|
|
956 ** SQLite normally do not need to invoke either of these routines.
|
|
|
957 **
|
|
|
958 ** A call to sqlite3_initialize() is an "effective" call if it is
|
|
|
959 ** the first time sqlite3_initialize() is invoked during the lifetime of
|
|
|
960 ** the process, or if it is the first time sqlite3_initialize() is invoked
|
|
|
961 ** following a call to sqlite3_shutdown(). ^(Only an effective call
|
|
|
962 ** of sqlite3_initialize() does any initialization. All other calls
|
|
|
963 ** are harmless no-ops.)^
|
|
|
964 **
|
|
|
965 ** A call to sqlite3_shutdown() is an "effective" call if it is the first
|
|
|
966 ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
|
|
|
967 ** an effective call to sqlite3_shutdown() does any deinitialization.
|
|
|
968 ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
|
|
|
969 **
|
|
|
970 ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
|
|
|
971 ** is not. The sqlite3_shutdown() interface must only be called from a
|
|
|
972 ** single thread. All open [database connections] must be closed and all
|
|
|
973 ** other SQLite resources must be deallocated prior to invoking
|
|
|
974 ** sqlite3_shutdown().
|
|
|
975 **
|
|
|
976 ** Among other things, ^sqlite3_initialize() will invoke
|
|
|
977 ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
|
|
|
978 ** will invoke sqlite3_os_end().
|
|
|
979 **
|
|
|
980 ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
|
|
|
981 ** ^If for some reason, sqlite3_initialize() is unable to initialize
|
|
|
982 ** the library (perhaps it is unable to allocate a needed resource such
|
|
|
983 ** as a mutex) it returns an [error code] other than [SQLITE_OK].
|
|
|
984 **
|
|
|
985 ** ^The sqlite3_initialize() routine is called internally by many other
|
|
|
986 ** SQLite interfaces so that an application usually does not need to
|
|
|
987 ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
|
|
|
988 ** calls sqlite3_initialize() so the SQLite library will be automatically
|
|
|
989 ** initialized when [sqlite3_open()] is called if it has not be initialized
|
|
|
990 ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
|
|
|
991 ** compile-time option, then the automatic calls to sqlite3_initialize()
|
|
|
992 ** are omitted and the application must call sqlite3_initialize() directly
|
|
|
993 ** prior to using any other SQLite interface. For maximum portability,
|
|
|
994 ** it is recommended that applications always invoke sqlite3_initialize()
|
|
|
995 ** directly prior to using any other SQLite interface. Future releases
|
|
|
996 ** of SQLite may require this. In other words, the behavior exhibited
|
|
|
997 ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
|
|
|
998 ** default behavior in some future release of SQLite.
|
|
|
999 **
|
|
|
1000 ** The sqlite3_os_init() routine does operating-system specific
|
|
|
1001 ** initialization of the SQLite library. The sqlite3_os_end()
|
|
|
1002 ** routine undoes the effect of sqlite3_os_init(). Typical tasks
|
|
|
1003 ** performed by these routines include allocation or deallocation
|
|
|
1004 ** of static resources, initialization of global variables,
|
|
|
1005 ** setting up a default [sqlite3_vfs] module, or setting up
|
|
|
1006 ** a default configuration using [sqlite3_config()].
|
|
|
1007 **
|
|
|
1008 ** The application should never invoke either sqlite3_os_init()
|
|
|
1009 ** or sqlite3_os_end() directly. The application should only invoke
|
|
|
1010 ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
|
|
|
1011 ** interface is called automatically by sqlite3_initialize() and
|
|
|
1012 ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
|
|
|
1013 ** implementations for sqlite3_os_init() and sqlite3_os_end()
|
|
|
1014 ** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
|
|
|
1015 ** When [custom builds | built for other platforms]
|
|
|
1016 ** (using the [SQLITE_OS_OTHER=1] compile-time
|
|
|
1017 ** option) the application must supply a suitable implementation for
|
|
|
1018 ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
|
|
|
1019 ** implementation of sqlite3_os_init() or sqlite3_os_end()
|
|
|
1020 ** must return [SQLITE_OK] on success and some other [error code] upon
|
|
|
1021 ** failure.
|
|
|
1022 */
|
|
|
1023 SQLITE_API int sqlite3_initialize(void);
|
|
|
1024 SQLITE_API int sqlite3_shutdown(void);
|
|
|
1025 SQLITE_API int sqlite3_os_init(void);
|
|
|
1026 SQLITE_API int sqlite3_os_end(void);
|
|
|
1027
|
|
|
1028 /*
|
|
|
1029 ** CAPI3REF: Configuring The SQLite Library
|
|
|
1030 **
|
|
|
1031 ** The sqlite3_config() interface is used to make global configuration
|
|
|
1032 ** changes to SQLite in order to tune SQLite to the specific needs of
|
|
|
1033 ** the application. The default configuration is recommended for most
|
|
|
1034 ** applications and so this routine is usually not necessary. It is
|
|
|
1035 ** provided to support rare applications with unusual needs.
|
|
|
1036 **
|
|
|
1037 ** The sqlite3_config() interface is not threadsafe. The application
|
|
|
1038 ** must insure that no other SQLite interfaces are invoked by other
|
|
|
1039 ** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
|
|
|
1040 ** may only be invoked prior to library initialization using
|
|
|
1041 ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
|
|
|
1042 ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
|
|
|
1043 ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
|
|
|
1044 ** Note, however, that ^sqlite3_config() can be called as part of the
|
|
|
1045 ** implementation of an application-defined [sqlite3_os_init()].
|
|
|
1046 **
|
|
|
1047 ** The first argument to sqlite3_config() is an integer
|
|
|
1048 ** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines
|
|
|
1049 ** what property of SQLite is to be configured. Subsequent arguments
|
|
|
1050 ** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option]
|
|
|
1051 ** in the first argument.
|
|
|
1052 **
|
|
|
1053 ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
|
|
|
1054 ** ^If the option is unknown or SQLite is unable to set the option
|
|
|
1055 ** then this routine returns a non-zero [error code].
|
|
|
1056 */
|
|
|
1057 SQLITE_API int sqlite3_config(int, ...);
|
|
|
1058
|
|
|
1059 /*
|
|
|
1060 ** CAPI3REF: Configure database connections
|
|
|
1061 **
|
|
|
1062 ** The sqlite3_db_config() interface is used to make configuration
|
|
|
1063 ** changes to a [database connection]. The interface is similar to
|
|
|
1064 ** [sqlite3_config()] except that the changes apply to a single
|
|
|
1065 ** [database connection] (specified in the first argument). The
|
|
|
1066 ** sqlite3_db_config() interface should only be used immediately after
|
|
|
1067 ** the database connection is created using [sqlite3_open()],
|
|
|
1068 ** [sqlite3_open16()], or [sqlite3_open_v2()].
|
|
|
1069 **
|
|
|
1070 ** The second argument to sqlite3_db_config(D,V,...) is the
|
|
|
1071 ** configuration verb - an integer code that indicates what
|
|
|
1072 ** aspect of the [database connection] is being configured.
|
|
|
1073 ** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
|
|
|
1074 ** New verbs are likely to be added in future releases of SQLite.
|
|
|
1075 ** Additional arguments depend on the verb.
|
|
|
1076 **
|
|
|
1077 ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
|
|
|
1078 ** the call is considered successful.
|
|
|
1079 */
|
|
|
1080 SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
|
|
|
1081
|
|
|
1082 /*
|
|
|
1083 ** CAPI3REF: Memory Allocation Routines
|
|
|
1084 **
|
|
|
1085 ** An instance of this object defines the interface between SQLite
|
|
|
1086 ** and low-level memory allocation routines.
|
|
|
1087 **
|
|
|
1088 ** This object is used in only one place in the SQLite interface.
|
|
|
1089 ** A pointer to an instance of this object is the argument to
|
|
|
1090 ** [sqlite3_config()] when the configuration option is
|
|
|
1091 ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
|
|
|
1092 ** By creating an instance of this object
|
|
|
1093 ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
|
|
|
1094 ** during configuration, an application can specify an alternative
|
|
|
1095 ** memory allocation subsystem for SQLite to use for all of its
|
|
|
1096 ** dynamic memory needs.
|
|
|
1097 **
|
|
|
1098 ** Note that SQLite comes with several [built-in memory allocators]
|
|
|
1099 ** that are perfectly adequate for the overwhelming majority of applications
|
|
|
1100 ** and that this object is only useful to a tiny minority of applications
|
|
|
1101 ** with specialized memory allocation requirements. This object is
|
|
|
1102 ** also used during testing of SQLite in order to specify an alternative
|
|
|
1103 ** memory allocator that simulates memory out-of-memory conditions in
|
|
|
1104 ** order to verify that SQLite recovers gracefully from such
|
|
|
1105 ** conditions.
|
|
|
1106 **
|
|
|
1107 ** The xMalloc and xFree methods must work like the
|
|
|
1108 ** malloc() and free() functions from the standard C library.
|
|
|
1109 ** The xRealloc method must work like realloc() from the standard C library
|
|
|
1110 ** with the exception that if the second argument to xRealloc is zero,
|
|
|
1111 ** xRealloc must be a no-op - it must not perform any allocation or
|
|
|
1112 ** deallocation. ^SQLite guarantees that the second argument to
|
|
|
1113 ** xRealloc is always a value returned by a prior call to xRoundup.
|
|
|
1114 ** And so in cases where xRoundup always returns a positive number,
|
|
|
1115 ** xRealloc can perform exactly as the standard library realloc() and
|
|
|
1116 ** still be in compliance with this specification.
|
|
|
1117 **
|
|
|
1118 ** xSize should return the allocated size of a memory allocation
|
|
|
1119 ** previously obtained from xMalloc or xRealloc. The allocated size
|
|
|
1120 ** is always at least as big as the requested size but may be larger.
|
|
|
1121 **
|
|
|
1122 ** The xRoundup method returns what would be the allocated size of
|
|
|
1123 ** a memory allocation given a particular requested size. Most memory
|
|
|
1124 ** allocators round up memory allocations at least to the next multiple
|
|
|
1125 ** of 8. Some allocators round up to a larger multiple or to a power of 2.
|
|
|
1126 ** Every memory allocation request coming in through [sqlite3_malloc()]
|
|
|
1127 ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
|
|
|
1128 ** that causes the corresponding memory allocation to fail.
|
|
|
1129 **
|
|
|
1130 ** The xInit method initializes the memory allocator. (For example,
|
|
|
1131 ** it might allocate any require mutexes or initialize internal data
|
|
|
1132 ** structures. The xShutdown method is invoked (indirectly) by
|
|
|
1133 ** [sqlite3_shutdown()] and should deallocate any resources acquired
|
|
|
1134 ** by xInit. The pAppData pointer is used as the only parameter to
|
|
|
1135 ** xInit and xShutdown.
|
|
|
1136 **
|
|
|
1137 ** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
|
|
|
1138 ** the xInit method, so the xInit method need not be threadsafe. The
|
|
|
1139 ** xShutdown method is only called from [sqlite3_shutdown()] so it does
|
|
|
1140 ** not need to be threadsafe either. For all other methods, SQLite
|
|
|
1141 ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
|
|
|
1142 ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
|
|
|
1143 ** it is by default) and so the methods are automatically serialized.
|
|
|
1144 ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
|
|
|
1145 ** methods must be threadsafe or else make their own arrangements for
|
|
|
1146 ** serialization.
|
|
|
1147 **
|
|
|
1148 ** SQLite will never invoke xInit() more than once without an intervening
|
|
|
1149 ** call to xShutdown().
|
|
|
1150 */
|
|
|
1151 typedef struct sqlite3_mem_methods sqlite3_mem_methods;
|
|
|
1152 struct sqlite3_mem_methods {
|
|
|
1153 void *(*xMalloc)(int); /* Memory allocation function */
|
|
|
1154 void (*xFree)(void*); /* Free a prior allocation */
|
|
|
1155 void *(*xRealloc)(void*,int); /* Resize an allocation */
|
|
|
1156 int (*xSize)(void*); /* Return the size of an allocation */
|
|
|
1157 int (*xRoundup)(int); /* Round up request size to allocation size */
|
|
|
1158 int (*xInit)(void*); /* Initialize the memory allocator */
|
|
|
1159 void (*xShutdown)(void*); /* Deinitialize the memory allocator */
|
|
|
1160 void *pAppData; /* Argument to xInit() and xShutdown() */
|
|
|
1161 };
|
|
|
1162
|
|
|
1163 /*
|
|
|
1164 ** CAPI3REF: Configuration Options
|
|
|
1165 **
|
|
|
1166 ** These constants are the available integer configuration options that
|
|
|
1167 ** can be passed as the first argument to the [sqlite3_config()] interface.
|
|
|
1168 **
|
|
|
1169 ** New configuration options may be added in future releases of SQLite.
|
|
|
1170 ** Existing configuration options might be discontinued. Applications
|
|
|
1171 ** should check the return code from [sqlite3_config()] to make sure that
|
|
|
1172 ** the call worked. The [sqlite3_config()] interface will return a
|
|
|
1173 ** non-zero [error code] if a discontinued or unsupported configuration option
|
|
|
1174 ** is invoked.
|
|
|
1175 **
|
|
|
1176 ** <dl>
|
|
|
1177 ** <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
|
|
|
1178 ** <dd>There are no arguments to this option. ^This option sets the
|
|
|
1179 ** [threading mode] to Single-thread. In other words, it disables
|
|
|
1180 ** all mutexing and puts SQLite into a mode where it can only be used
|
|
|
1181 ** by a single thread. ^If SQLite is compiled with
|
|
|
1182 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
|
|
|
1183 ** it is not possible to change the [threading mode] from its default
|
|
|
1184 ** value of Single-thread and so [sqlite3_config()] will return
|
|
|
1185 ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
|
|
|
1186 ** configuration option.</dd>
|
|
|
1187 **
|
|
|
1188 ** <dt>SQLITE_CONFIG_MULTITHREAD</dt>
|
|
|
1189 ** <dd>There are no arguments to this option. ^This option sets the
|
|
|
1190 ** [threading mode] to Multi-thread. In other words, it disables
|
|
|
1191 ** mutexing on [database connection] and [prepared statement] objects.
|
|
|
1192 ** The application is responsible for serializing access to
|
|
|
1193 ** [database connections] and [prepared statements]. But other mutexes
|
|
|
1194 ** are enabled so that SQLite will be safe to use in a multi-threaded
|
|
|
1195 ** environment as long as no two threads attempt to use the same
|
|
|
1196 ** [database connection] at the same time. ^If SQLite is compiled with
|
|
|
1197 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
|
|
|
1198 ** it is not possible to set the Multi-thread [threading mode] and
|
|
|
1199 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
|
|
|
1200 ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
|
|
|
1201 **
|
|
|
1202 ** <dt>SQLITE_CONFIG_SERIALIZED</dt>
|
|
|
1203 ** <dd>There are no arguments to this option. ^This option sets the
|
|
|
1204 ** [threading mode] to Serialized. In other words, this option enables
|
|
|
1205 ** all mutexes including the recursive
|
|
|
1206 ** mutexes on [database connection] and [prepared statement] objects.
|
|
|
1207 ** In this mode (which is the default when SQLite is compiled with
|
|
|
1208 ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
|
|
|
1209 ** to [database connections] and [prepared statements] so that the
|
|
|
1210 ** application is free to use the same [database connection] or the
|
|
|
1211 ** same [prepared statement] in different threads at the same time.
|
|
|
1212 ** ^If SQLite is compiled with
|
|
|
1213 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
|
|
|
1214 ** it is not possible to set the Serialized [threading mode] and
|
|
|
1215 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
|
|
|
1216 ** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
|
|
|
1217 **
|
|
|
1218 ** <dt>SQLITE_CONFIG_MALLOC</dt>
|
|
|
1219 ** <dd> ^(This option takes a single argument which is a pointer to an
|
|
|
1220 ** instance of the [sqlite3_mem_methods] structure. The argument specifies
|
|
|
1221 ** alternative low-level memory allocation routines to be used in place of
|
|
|
1222 ** the memory allocation routines built into SQLite.)^ ^SQLite makes
|
|
|
1223 ** its own private copy of the content of the [sqlite3_mem_methods] structure
|
|
|
1224 ** before the [sqlite3_config()] call returns.</dd>
|
|
|
1225 **
|
|
|
1226 ** <dt>SQLITE_CONFIG_GETMALLOC</dt>
|
|
|
1227 ** <dd> ^(This option takes a single argument which is a pointer to an
|
|
|
1228 ** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods]
|
|
|
1229 ** structure is filled with the currently defined memory allocation routines.)^
|
|
|
1230 ** This option can be used to overload the default memory allocation
|
|
|
1231 ** routines with a wrapper that simulations memory allocation failure or
|
|
|
1232 ** tracks memory usage, for example. </dd>
|
|
|
1233 **
|
|
|
1234 ** <dt>SQLITE_CONFIG_MEMSTATUS</dt>
|
|
|
1235 ** <dd> ^This option takes single argument of type int, interpreted as a
|
|
|
1236 ** boolean, which enables or disables the collection of memory allocation
|
|
|
1237 ** statistics. ^(When memory allocation statistics are disabled, the
|
|
|
1238 ** following SQLite interfaces become non-operational:
|
|
|
1239 ** <ul>
|
|
|
1240 ** <li> [sqlite3_memory_used()]
|
|
|
1241 ** <li> [sqlite3_memory_highwater()]
|
|
|
1242 ** <li> [sqlite3_soft_heap_limit()]
|
|
|
1243 ** <li> [sqlite3_status()]
|
|
|
1244 ** </ul>)^
|
|
|
1245 ** ^Memory allocation statistics are enabled by default unless SQLite is
|
|
|
1246 ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
|
|
|
1247 ** allocation statistics are disabled by default.
|
|
|
1248 ** </dd>
|
|
|
1249 **
|
|
|
1250 ** <dt>SQLITE_CONFIG_SCRATCH</dt>
|
|
|
1251 ** <dd> ^This option specifies a static memory buffer that SQLite can use for
|
|
|
1252 ** scratch memory. There are three arguments: A pointer an 8-byte
|
|
|
1253 ** aligned memory buffer from which the scrach allocations will be
|
|
|
1254 ** drawn, the size of each scratch allocation (sz),
|
|
|
1255 ** and the maximum number of scratch allocations (N). The sz
|
|
|
1256 ** argument must be a multiple of 16. The sz parameter should be a few bytes
|
|
|
1257 ** larger than the actual scratch space required due to internal overhead.
|
|
|
1258 ** The first argument must be a pointer to an 8-byte aligned buffer
|
|
|
1259 ** of at least sz*N bytes of memory.
|
|
|
1260 ** ^SQLite will use no more than one scratch buffer per thread. So
|
|
|
1261 ** N should be set to the expected maximum number of threads. ^SQLite will
|
|
|
1262 ** never require a scratch buffer that is more than 6 times the database
|
|
|
1263 ** page size. ^If SQLite needs needs additional scratch memory beyond
|
|
|
1264 ** what is provided by this configuration option, then
|
|
|
1265 ** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
|
|
|
1266 **
|
|
|
1267 ** <dt>SQLITE_CONFIG_PAGECACHE</dt>
|
|
|
1268 ** <dd> ^This option specifies a static memory buffer that SQLite can use for
|
|
|
1269 ** the database page cache with the default page cache implemenation.
|
|
|
1270 ** This configuration should not be used if an application-define page
|
|
|
1271 ** cache implementation is loaded using the SQLITE_CONFIG_PCACHE option.
|
|
|
1272 ** There are three arguments to this option: A pointer to 8-byte aligned
|
|
|
1273 ** memory, the size of each page buffer (sz), and the number of pages (N).
|
|
|
1274 ** The sz argument should be the size of the largest database page
|
|
|
1275 ** (a power of two between 512 and 32768) plus a little extra for each
|
|
|
1276 ** page header. ^The page header size is 20 to 40 bytes depending on
|
|
|
1277 ** the host architecture. ^It is harmless, apart from the wasted memory,
|
|
|
1278 ** to make sz a little too large. The first
|
|
|
1279 ** argument should point to an allocation of at least sz*N bytes of memory.
|
|
|
1280 ** ^SQLite will use the memory provided by the first argument to satisfy its
|
|
|
1281 ** memory needs for the first N pages that it adds to cache. ^If additional
|
|
|
1282 ** page cache memory is needed beyond what is provided by this option, then
|
|
|
1283 ** SQLite goes to [sqlite3_malloc()] for the additional storage space.
|
|
|
1284 ** ^The implementation might use one or more of the N buffers to hold
|
|
|
1285 ** memory accounting information. The pointer in the first argument must
|
|
|
1286 ** be aligned to an 8-byte boundary or subsequent behavior of SQLite
|
|
|
1287 ** will be undefined.</dd>
|
|
|
1288 **
|
|
|
1289 ** <dt>SQLITE_CONFIG_HEAP</dt>
|
|
|
1290 ** <dd> ^This option specifies a static memory buffer that SQLite will use
|
|
|
1291 ** for all of its dynamic memory allocation needs beyond those provided
|
|
|
1292 ** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
|
|
|
1293 ** There are three arguments: An 8-byte aligned pointer to the memory,
|
|
|
1294 ** the number of bytes in the memory buffer, and the minimum allocation size.
|
|
|
1295 ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
|
|
|
1296 ** to using its default memory allocator (the system malloc() implementation),
|
|
|
1297 ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
|
|
|
1298 ** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
|
|
|
1299 ** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
|
|
|
1300 ** allocator is engaged to handle all of SQLites memory allocation needs.
|
|
|
1301 ** The first pointer (the memory pointer) must be aligned to an 8-byte
|
|
|
1302 ** boundary or subsequent behavior of SQLite will be undefined.</dd>
|
|
|
1303 **
|
|
|
1304 ** <dt>SQLITE_CONFIG_MUTEX</dt>
|
|
|
1305 ** <dd> ^(This option takes a single argument which is a pointer to an
|
|
|
1306 ** instance of the [sqlite3_mutex_methods] structure. The argument specifies
|
|
|
1307 ** alternative low-level mutex routines to be used in place
|
|
|
1308 ** the mutex routines built into SQLite.)^ ^SQLite makes a copy of the
|
|
|
1309 ** content of the [sqlite3_mutex_methods] structure before the call to
|
|
|
1310 ** [sqlite3_config()] returns. ^If SQLite is compiled with
|
|
|
1311 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
|
|
|
1312 ** the entire mutexing subsystem is omitted from the build and hence calls to
|
|
|
1313 ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
|
|
|
1314 ** return [SQLITE_ERROR].</dd>
|
|
|
1315 **
|
|
|
1316 ** <dt>SQLITE_CONFIG_GETMUTEX</dt>
|
|
|
1317 ** <dd> ^(This option takes a single argument which is a pointer to an
|
|
|
1318 ** instance of the [sqlite3_mutex_methods] structure. The
|
|
|
1319 ** [sqlite3_mutex_methods]
|
|
|
1320 ** structure is filled with the currently defined mutex routines.)^
|
|
|
1321 ** This option can be used to overload the default mutex allocation
|
|
|
1322 ** routines with a wrapper used to track mutex usage for performance
|
|
|
1323 ** profiling or testing, for example. ^If SQLite is compiled with
|
|
|
1324 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
|
|
|
1325 ** the entire mutexing subsystem is omitted from the build and hence calls to
|
|
|
1326 ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
|
|
|
1327 ** return [SQLITE_ERROR].</dd>
|
|
|
1328 **
|
|
|
1329 ** <dt>SQLITE_CONFIG_LOOKASIDE</dt>
|
|
|
1330 ** <dd> ^(This option takes two arguments that determine the default
|
|
|
1331 ** memory allocation for the lookaside memory allocator on each
|
|
|
1332 ** [database connection]. The first argument is the
|
|
|
1333 ** size of each lookaside buffer slot and the second is the number of
|
|
|
1334 ** slots allocated to each database connection.)^ ^(This option sets the
|
|
|
1335 ** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
|
|
|
1336 ** verb to [sqlite3_db_config()] can be used to change the lookaside
|
|
|
1337 ** configuration on individual connections.)^ </dd>
|
|
|
1338 **
|
|
|
1339 ** <dt>SQLITE_CONFIG_PCACHE</dt>
|
|
|
1340 ** <dd> ^(This option takes a single argument which is a pointer to
|
|
|
1341 ** an [sqlite3_pcache_methods] object. This object specifies the interface
|
|
|
1342 ** to a custom page cache implementation.)^ ^SQLite makes a copy of the
|
|
|
1343 ** object and uses it for page cache memory allocations.</dd>
|
|
|
1344 **
|
|
|
1345 ** <dt>SQLITE_CONFIG_GETPCACHE</dt>
|
|
|
1346 ** <dd> ^(This option takes a single argument which is a pointer to an
|
|
|
1347 ** [sqlite3_pcache_methods] object. SQLite copies of the current
|
|
|
1348 ** page cache implementation into that object.)^ </dd>
|
|
|
1349 **
|
|
|
1350 ** <dt>SQLITE_CONFIG_LOG</dt>
|
|
|
1351 ** <dd> ^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
|
|
|
1352 ** function with a call signature of void(*)(void*,int,const char*),
|
|
|
1353 ** and a pointer to void. ^If the function pointer is not NULL, it is
|
|
|
1354 ** invoked by [sqlite3_log()] to process each logging event. ^If the
|
|
|
1355 ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
|
|
|
1356 ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
|
|
|
1357 ** passed through as the first parameter to the application-defined logger
|
|
|
1358 ** function whenever that function is invoked. ^The second parameter to
|
|
|
1359 ** the logger function is a copy of the first parameter to the corresponding
|
|
|
1360 ** [sqlite3_log()] call and is intended to be a [result code] or an
|
|
|
1361 ** [extended result code]. ^The third parameter passed to the logger is
|
|
|
1362 ** log message after formatting via [sqlite3_snprintf()].
|
|
|
1363 ** The SQLite logging interface is not reentrant; the logger function
|
|
|
1364 ** supplied by the application must not invoke any SQLite interface.
|
|
|
1365 ** In a multi-threaded application, the application-defined logger
|
|
|
1366 ** function must be threadsafe. </dd>
|
|
|
1367 **
|
|
|
1368 ** </dl>
|
|
|
1369 */
|
|
|
1370 #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
|
|
|
1371 #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
|
|
|
1372 #define SQLITE_CONFIG_SERIALIZED 3 /* nil */
|
|
|
1373 #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
|
|
|
1374 #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
|
|
|
1375 #define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
|
|
|
1376 #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
|
|
|
1377 #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
|
|
|
1378 #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
|
|
|
1379 #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
|
|
|
1380 #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
|
|
|
1381 /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
|
|
|
1382 #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
|
|
|
1383 #define SQLITE_CONFIG_PCACHE 14 /* sqlite3_pcache_methods* */
|
|
|
1384 #define SQLITE_CONFIG_GETPCACHE 15 /* sqlite3_pcache_methods* */
|
|
|
1385 #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
|
|
|
1386
|
|
|
1387 /*
|
|
|
1388 ** CAPI3REF: Database Connection Configuration Options
|
|
|
1389 **
|
|
|
1390 ** These constants are the available integer configuration options that
|
|
|
1391 ** can be passed as the second argument to the [sqlite3_db_config()] interface.
|
|
|
1392 **
|
|
|
1393 ** New configuration options may be added in future releases of SQLite.
|
|
|
1394 ** Existing configuration options might be discontinued. Applications
|
|
|
1395 ** should check the return code from [sqlite3_db_config()] to make sure that
|
|
|
1396 ** the call worked. ^The [sqlite3_db_config()] interface will return a
|
|
|
1397 ** non-zero [error code] if a discontinued or unsupported configuration option
|
|
|
1398 ** is invoked.
|
|
|
1399 **
|
|
|
1400 ** <dl>
|
|
|
1401 ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
|
|
|
1402 ** <dd> ^This option takes three additional arguments that determine the
|
|
|
1403 ** [lookaside memory allocator] configuration for the [database connection].
|
|
|
1404 ** ^The first argument (the third parameter to [sqlite3_db_config()] is a
|
|
|
1405 ** pointer to an memory buffer to use for lookaside memory.
|
|
|
1406 ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
|
|
|
1407 ** may be NULL in which case SQLite will allocate the
|
|
|
1408 ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
|
|
|
1409 ** size of each lookaside buffer slot. ^The third argument is the number of
|
|
|
1410 ** slots. The size of the buffer in the first argument must be greater than
|
|
|
1411 ** or equal to the product of the second and third arguments. The buffer
|
|
|
1412 ** must be aligned to an 8-byte boundary. ^If the second argument to
|
|
|
1413 ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
|
|
|
1414 ** rounded down to the next smaller
|
|
|
1415 ** multiple of 8. See also: [SQLITE_CONFIG_LOOKASIDE]</dd>
|
|
|
1416 **
|
|
|
1417 ** </dl>
|
|
|
1418 */
|
|
|
1419 #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
|
|
|
1420
|
|
|
1421
|
|
|
1422 /*
|
|
|
1423 ** CAPI3REF: Enable Or Disable Extended Result Codes
|
|
|
1424 **
|
|
|
1425 ** ^The sqlite3_extended_result_codes() routine enables or disables the
|
|
|
1426 ** [extended result codes] feature of SQLite. ^The extended result
|
|
|
1427 ** codes are disabled by default for historical compatibility.
|
|
|
1428 */
|
|
|
1429 SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
|
|
|
1430
|
|
|
1431 /*
|
|
|
1432 ** CAPI3REF: Last Insert Rowid
|
|
|
1433 **
|
|
|
1434 ** ^Each entry in an SQLite table has a unique 64-bit signed
|
|
|
1435 ** integer key called the [ROWID | "rowid"]. ^The rowid is always available
|
|
|
1436 ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
|
|
|
1437 ** names are not also used by explicitly declared columns. ^If
|
|
|
1438 ** the table has a column of type [INTEGER PRIMARY KEY] then that column
|
|
|
1439 ** is another alias for the rowid.
|
|
|
1440 **
|
|
|
1441 ** ^This routine returns the [rowid] of the most recent
|
|
|
1442 ** successful [INSERT] into the database from the [database connection]
|
|
|
1443 ** in the first argument. ^If no successful [INSERT]s
|
|
|
1444 ** have ever occurred on that database connection, zero is returned.
|
|
|
1445 **
|
|
|
1446 ** ^(If an [INSERT] occurs within a trigger, then the [rowid] of the inserted
|
|
|
1447 ** row is returned by this routine as long as the trigger is running.
|
|
|
1448 ** But once the trigger terminates, the value returned by this routine
|
|
|
1449 ** reverts to the last value inserted before the trigger fired.)^
|
|
|
1450 **
|
|
|
1451 ** ^An [INSERT] that fails due to a constraint violation is not a
|
|
|
1452 ** successful [INSERT] and does not change the value returned by this
|
|
|
1453 ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
|
|
|
1454 ** and INSERT OR ABORT make no changes to the return value of this
|
|
|
1455 ** routine when their insertion fails. ^(When INSERT OR REPLACE
|
|
|
1456 ** encounters a constraint violation, it does not fail. The
|
|
|
1457 ** INSERT continues to completion after deleting rows that caused
|
|
|
1458 ** the constraint problem so INSERT OR REPLACE will always change
|
|
|
1459 ** the return value of this interface.)^
|
|
|
1460 **
|
|
|
1461 ** ^For the purposes of this routine, an [INSERT] is considered to
|
|
|
1462 ** be successful even if it is subsequently rolled back.
|
|
|
1463 **
|
|
|
1464 ** This function is accessible to SQL statements via the
|
|
|
1465 ** [last_insert_rowid() SQL function].
|
|
|
1466 **
|
|
|
1467 ** If a separate thread performs a new [INSERT] on the same
|
|
|
1468 ** database connection while the [sqlite3_last_insert_rowid()]
|
|
|
1469 ** function is running and thus changes the last insert [rowid],
|
|
|
1470 ** then the value returned by [sqlite3_last_insert_rowid()] is
|
|
|
1471 ** unpredictable and might not equal either the old or the new
|
|
|
1472 ** last insert [rowid].
|
|
|
1473 */
|
|
|
1474 SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
|
|
|
1475
|
|
|
1476 /*
|
|
|
1477 ** CAPI3REF: Count The Number Of Rows Modified
|
|
|
1478 **
|
|
|
1479 ** ^This function returns the number of database rows that were changed
|
|
|
1480 ** or inserted or deleted by the most recently completed SQL statement
|
|
|
1481 ** on the [database connection] specified by the first parameter.
|
|
|
1482 ** ^(Only changes that are directly specified by the [INSERT], [UPDATE],
|
|
|
1483 ** or [DELETE] statement are counted. Auxiliary changes caused by
|
|
|
1484 ** triggers or [foreign key actions] are not counted.)^ Use the
|
|
|
1485 ** [sqlite3_total_changes()] function to find the total number of changes
|
|
|
1486 ** including changes caused by triggers and foreign key actions.
|
|
|
1487 **
|
|
|
1488 ** ^Changes to a view that are simulated by an [INSTEAD OF trigger]
|
|
|
1489 ** are not counted. Only real table changes are counted.
|
|
|
1490 **
|
|
|
1491 ** ^(A "row change" is a change to a single row of a single table
|
|
|
1492 ** caused by an INSERT, DELETE, or UPDATE statement. Rows that
|
|
|
1493 ** are changed as side effects of [REPLACE] constraint resolution,
|
|
|
1494 ** rollback, ABORT processing, [DROP TABLE], or by any other
|
|
|
1495 ** mechanisms do not count as direct row changes.)^
|
|
|
1496 **
|
|
|
1497 ** A "trigger context" is a scope of execution that begins and
|
|
|
1498 ** ends with the script of a [CREATE TRIGGER | trigger].
|
|
|
1499 ** Most SQL statements are
|
|
|
1500 ** evaluated outside of any trigger. This is the "top level"
|
|
|
1501 ** trigger context. If a trigger fires from the top level, a
|
|
|
1502 ** new trigger context is entered for the duration of that one
|
|
|
1503 ** trigger. Subtriggers create subcontexts for their duration.
|
|
|
1504 **
|
|
|
1505 ** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
|
|
|
1506 ** not create a new trigger context.
|
|
|
1507 **
|
|
|
1508 ** ^This function returns the number of direct row changes in the
|
|
|
1509 ** most recent INSERT, UPDATE, or DELETE statement within the same
|
|
|
1510 ** trigger context.
|
|
|
1511 **
|
|
|
1512 ** ^Thus, when called from the top level, this function returns the
|
|
|
1513 ** number of changes in the most recent INSERT, UPDATE, or DELETE
|
|
|
1514 ** that also occurred at the top level. ^(Within the body of a trigger,
|
|
|
1515 ** the sqlite3_changes() interface can be called to find the number of
|
|
|
1516 ** changes in the most recently completed INSERT, UPDATE, or DELETE
|
|
|
1517 ** statement within the body of the same trigger.
|
|
|
1518 ** However, the number returned does not include changes
|
|
|
1519 ** caused by subtriggers since those have their own context.)^
|
|
|
1520 **
|
|
|
1521 ** See also the [sqlite3_total_changes()] interface, the
|
|
|
1522 ** [count_changes pragma], and the [changes() SQL function].
|
|
|
1523 **
|
|
|
1524 ** If a separate thread makes changes on the same database connection
|
|
|
1525 ** while [sqlite3_changes()] is running then the value returned
|
|
|
1526 ** is unpredictable and not meaningful.
|
|
|
1527 */
|
|
|
1528 SQLITE_API int sqlite3_changes(sqlite3*);
|
|
|
1529
|
|
|
1530 /*
|
|
|
1531 ** CAPI3REF: Total Number Of Rows Modified
|
|
|
1532 **
|
|
|
1533 ** ^This function returns the number of row changes caused by [INSERT],
|
|
|
1534 ** [UPDATE] or [DELETE] statements since the [database connection] was opened.
|
|
|
1535 ** ^(The count returned by sqlite3_total_changes() includes all changes
|
|
|
1536 ** from all [CREATE TRIGGER | trigger] contexts and changes made by
|
|
|
1537 ** [foreign key actions]. However,
|
|
|
1538 ** the count does not include changes used to implement [REPLACE] constraints,
|
|
|
1539 ** do rollbacks or ABORT processing, or [DROP TABLE] processing. The
|
|
|
1540 ** count does not include rows of views that fire an [INSTEAD OF trigger],
|
|
|
1541 ** though if the INSTEAD OF trigger makes changes of its own, those changes
|
|
|
1542 ** are counted.)^
|
|
|
1543 ** ^The sqlite3_total_changes() function counts the changes as soon as
|
|
|
1544 ** the statement that makes them is completed (when the statement handle
|
|
|
1545 ** is passed to [sqlite3_reset()] or [sqlite3_finalize()]).
|
|
|
1546 **
|
|
|
1547 ** See also the [sqlite3_changes()] interface, the
|
|
|
1548 ** [count_changes pragma], and the [total_changes() SQL function].
|
|
|
1549 **
|
|
|
1550 ** If a separate thread makes changes on the same database connection
|
|
|
1551 ** while [sqlite3_total_changes()] is running then the value
|
|
|
1552 ** returned is unpredictable and not meaningful.
|
|
|
1553 */
|
|
|
1554 SQLITE_API int sqlite3_total_changes(sqlite3*);
|
|
|
1555
|
|
|
1556 /*
|
|
|
1557 ** CAPI3REF: Interrupt A Long-Running Query
|
|
|
1558 **
|
|
|
1559 ** ^This function causes any pending database operation to abort and
|
|
|
1560 ** return at its earliest opportunity. This routine is typically
|
|
|
1561 ** called in response to a user action such as pressing "Cancel"
|
|
|
1562 ** or Ctrl-C where the user wants a long query operation to halt
|
|
|
1563 ** immediately.
|
|
|
1564 **
|
|
|
1565 ** ^It is safe to call this routine from a thread different from the
|
|
|
1566 ** thread that is currently running the database operation. But it
|
|
|
1567 ** is not safe to call this routine with a [database connection] that
|
|
|
1568 ** is closed or might close before sqlite3_interrupt() returns.
|
|
|
1569 **
|
|
|
1570 ** ^If an SQL operation is very nearly finished at the time when
|
|
|
1571 ** sqlite3_interrupt() is called, then it might not have an opportunity
|
|
|
1572 ** to be interrupted and might continue to completion.
|
|
|
1573 **
|
|
|
1574 ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
|
|
|
1575 ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
|
|
|
1576 ** that is inside an explicit transaction, then the entire transaction
|
|
|
1577 ** will be rolled back automatically.
|
|
|
1578 **
|
|
|
1579 ** ^The sqlite3_interrupt(D) call is in effect until all currently running
|
|
|
1580 ** SQL statements on [database connection] D complete. ^Any new SQL statements
|
|
|
1581 ** that are started after the sqlite3_interrupt() call and before the
|
|
|
1582 ** running statements reaches zero are interrupted as if they had been
|
|
|
1583 ** running prior to the sqlite3_interrupt() call. ^New SQL statements
|
|
|
1584 ** that are started after the running statement count reaches zero are
|
|
|
1585 ** not effected by the sqlite3_interrupt().
|
|
|
1586 ** ^A call to sqlite3_interrupt(D) that occurs when there are no running
|
|
|
1587 ** SQL statements is a no-op and has no effect on SQL statements
|
|
|
1588 ** that are started after the sqlite3_interrupt() call returns.
|
|
|
1589 **
|
|
|
1590 ** If the database connection closes while [sqlite3_interrupt()]
|
|
|
1591 ** is running then bad things will likely happen.
|
|
|
1592 */
|
|
|
1593 SQLITE_API void sqlite3_interrupt(sqlite3*);
|
|
|
1594
|
|
|
1595 /*
|
|
|
1596 ** CAPI3REF: Determine If An SQL Statement Is Complete
|
|
|
1597 **
|
|
|
1598 ** These routines are useful during command-line input to determine if the
|
|
|
1599 ** currently entered text seems to form a complete SQL statement or
|
|
|
1600 ** if additional input is needed before sending the text into
|
|
|
1601 ** SQLite for parsing. ^These routines return 1 if the input string
|
|
|
1602 ** appears to be a complete SQL statement. ^A statement is judged to be
|
|
|
1603 ** complete if it ends with a semicolon token and is not a prefix of a
|
|
|
1604 ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
|
|
|
1605 ** string literals or quoted identifier names or comments are not
|
|
|
1606 ** independent tokens (they are part of the token in which they are
|
|
|
1607 ** embedded) and thus do not count as a statement terminator. ^Whitespace
|
|
|
1608 ** and comments that follow the final semicolon are ignored.
|
|
|
1609 **
|
|
|
1610 ** ^These routines return 0 if the statement is incomplete. ^If a
|
|
|
1611 ** memory allocation fails, then SQLITE_NOMEM is returned.
|
|
|
1612 **
|
|
|
1613 ** ^These routines do not parse the SQL statements thus
|
|
|
1614 ** will not detect syntactically incorrect SQL.
|
|
|
1615 **
|
|
|
1616 ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
|
|
|
1617 ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
|
|
|
1618 ** automatically by sqlite3_complete16(). If that initialization fails,
|
|
|
1619 ** then the return value from sqlite3_complete16() will be non-zero
|
|
|
1620 ** regardless of whether or not the input SQL is complete.)^
|
|
|
1621 **
|
|
|
1622 ** The input to [sqlite3_complete()] must be a zero-terminated
|
|
|
1623 ** UTF-8 string.
|
|
|
1624 **
|
|
|
1625 ** The input to [sqlite3_complete16()] must be a zero-terminated
|
|
|
1626 ** UTF-16 string in native byte order.
|
|
|
1627 */
|
|
|
1628 SQLITE_API int sqlite3_complete(const char *sql);
|
|
|
1629 SQLITE_API int sqlite3_complete16(const void *sql);
|
|
|
1630
|
|
|
1631 /*
|
|
|
1632 ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
|
|
|
1633 **
|
|
|
1634 ** ^This routine sets a callback function that might be invoked whenever
|
|
|
1635 ** an attempt is made to open a database table that another thread
|
|
|
1636 ** or process has locked.
|
|
|
1637 **
|
|
|
1638 ** ^If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
|
|
|
1639 ** is returned immediately upon encountering the lock. ^If the busy callback
|
|
|
1640 ** is not NULL, then the callback might be invoked with two arguments.
|
|
|
1641 **
|
|
|
1642 ** ^The first argument to the busy handler is a copy of the void* pointer which
|
|
|
1643 ** is the third argument to sqlite3_busy_handler(). ^The second argument to
|
|
|
1644 ** the busy handler callback is the number of times that the busy handler has
|
|
|
1645 ** been invoked for this locking event. ^If the
|
|
|
1646 ** busy callback returns 0, then no additional attempts are made to
|
|
|
1647 ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
|
|
|
1648 ** ^If the callback returns non-zero, then another attempt
|
|
|
1649 ** is made to open the database for reading and the cycle repeats.
|
|
|
1650 **
|
|
|
1651 ** The presence of a busy handler does not guarantee that it will be invoked
|
|
|
1652 ** when there is lock contention. ^If SQLite determines that invoking the busy
|
|
|
1653 ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
|
|
|
1654 ** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
|
|
|
1655 ** Consider a scenario where one process is holding a read lock that
|
|
|
1656 ** it is trying to promote to a reserved lock and
|
|
|
1657 ** a second process is holding a reserved lock that it is trying
|
|
|
1658 ** to promote to an exclusive lock. The first process cannot proceed
|
|
|
1659 ** because it is blocked by the second and the second process cannot
|
|
|
1660 ** proceed because it is blocked by the first. If both processes
|
|
|
1661 ** invoke the busy handlers, neither will make any progress. Therefore,
|
|
|
1662 ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
|
|
|
1663 ** will induce the first process to release its read lock and allow
|
|
|
1664 ** the second process to proceed.
|
|
|
1665 **
|
|
|
1666 ** ^The default busy callback is NULL.
|
|
|
1667 **
|
|
|
1668 ** ^The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
|
|
|
1669 ** when SQLite is in the middle of a large transaction where all the
|
|
|
1670 ** changes will not fit into the in-memory cache. SQLite will
|
|
|
1671 ** already hold a RESERVED lock on the database file, but it needs
|
|
|
1672 ** to promote this lock to EXCLUSIVE so that it can spill cache
|
|
|
1673 ** pages into the database file without harm to concurrent
|
|
|
1674 ** readers. ^If it is unable to promote the lock, then the in-memory
|
|
|
1675 ** cache will be left in an inconsistent state and so the error
|
|
|
1676 ** code is promoted from the relatively benign [SQLITE_BUSY] to
|
|
|
1677 ** the more severe [SQLITE_IOERR_BLOCKED]. ^This error code promotion
|
|
|
1678 ** forces an automatic rollback of the changes. See the
|
|
|
1679 ** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
|
|
|
1680 ** CorruptionFollowingBusyError</a> wiki page for a discussion of why
|
|
|
1681 ** this is important.
|
|
|
1682 **
|
|
|
1683 ** ^(There can only be a single busy handler defined for each
|
|
|
1684 ** [database connection]. Setting a new busy handler clears any
|
|
|
1685 ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
|
|
|
1686 ** will also set or clear the busy handler.
|
|
|
1687 **
|
|
|
1688 ** The busy callback should not take any actions which modify the
|
|
|
1689 ** database connection that invoked the busy handler. Any such actions
|
|
|
1690 ** result in undefined behavior.
|
|
|
1691 **
|
|
|
1692 ** A busy handler must not close the database connection
|
|
|
1693 ** or [prepared statement] that invoked the busy handler.
|
|
|
1694 */
|
|
|
1695 SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
|
|
|
1696
|
|
|
1697 /*
|
|
|
1698 ** CAPI3REF: Set A Busy Timeout
|
|
|
1699 **
|
|
|
1700 ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
|
|
|
1701 ** for a specified amount of time when a table is locked. ^The handler
|
|
|
1702 ** will sleep multiple times until at least "ms" milliseconds of sleeping
|
|
|
1703 ** have accumulated. ^After at least "ms" milliseconds of sleeping,
|
|
|
1704 ** the handler returns 0 which causes [sqlite3_step()] to return
|
|
|
1705 ** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
|
|
|
1706 **
|
|
|
1707 ** ^Calling this routine with an argument less than or equal to zero
|
|
|
1708 ** turns off all busy handlers.
|
|
|
1709 **
|
|
|
1710 ** ^(There can only be a single busy handler for a particular
|
|
|
1711 ** [database connection] any any given moment. If another busy handler
|
|
|
1712 ** was defined (using [sqlite3_busy_handler()]) prior to calling
|
|
|
1713 ** this routine, that other busy handler is cleared.)^
|
|
|
1714 */
|
|
|
1715 SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
|
|
|
1716
|
|
|
1717 /*
|
|
|
1718 ** CAPI3REF: Convenience Routines For Running Queries
|
|
|
1719 **
|
|
|
1720 ** Definition: A <b>result table</b> is memory data structure created by the
|
|
|
1721 ** [sqlite3_get_table()] interface. A result table records the
|
|
|
1722 ** complete query results from one or more queries.
|
|
|
1723 **
|
|
|
1724 ** The table conceptually has a number of rows and columns. But
|
|
|
1725 ** these numbers are not part of the result table itself. These
|
|
|
1726 ** numbers are obtained separately. Let N be the number of rows
|
|
|
1727 ** and M be the number of columns.
|
|
|
1728 **
|
|
|
1729 ** A result table is an array of pointers to zero-terminated UTF-8 strings.
|
|
|
1730 ** There are (N+1)*M elements in the array. The first M pointers point
|
|
|
1731 ** to zero-terminated strings that contain the names of the columns.
|
|
|
1732 ** The remaining entries all point to query results. NULL values result
|
|
|
1733 ** in NULL pointers. All other values are in their UTF-8 zero-terminated
|
|
|
1734 ** string representation as returned by [sqlite3_column_text()].
|
|
|
1735 **
|
|
|
1736 ** A result table might consist of one or more memory allocations.
|
|
|
1737 ** It is not safe to pass a result table directly to [sqlite3_free()].
|
|
|
1738 ** A result table should be deallocated using [sqlite3_free_table()].
|
|
|
1739 **
|
|
|
1740 ** As an example of the result table format, suppose a query result
|
|
|
1741 ** is as follows:
|
|
|
1742 **
|
|
|
1743 ** <blockquote><pre>
|
|
|
1744 ** Name | Age
|
|
|
1745 ** -----------------------
|
|
|
1746 ** Alice | 43
|
|
|
1747 ** Bob | 28
|
|
|
1748 ** Cindy | 21
|
|
|
1749 ** </pre></blockquote>
|
|
|
1750 **
|
|
|
1751 ** There are two column (M==2) and three rows (N==3). Thus the
|
|
|
1752 ** result table has 8 entries. Suppose the result table is stored
|
|
|
1753 ** in an array names azResult. Then azResult holds this content:
|
|
|
1754 **
|
|
|
1755 ** <blockquote><pre>
|
|
|
1756 ** azResult[0] = "Name";
|
|
|
1757 ** azResult[1] = "Age";
|
|
|
1758 ** azResult[2] = "Alice";
|
|
|
1759 ** azResult[3] = "43";
|
|
|
1760 ** azResult[4] = "Bob";
|
|
|
1761 ** azResult[5] = "28";
|
|
|
1762 ** azResult[6] = "Cindy";
|
|
|
1763 ** azResult[7] = "21";
|
|
|
1764 ** </pre></blockquote>
|
|
|
1765 **
|
|
|
1766 ** ^The sqlite3_get_table() function evaluates one or more
|
|
|
1767 ** semicolon-separated SQL statements in the zero-terminated UTF-8
|
|
|
1768 ** string of its 2nd parameter and returns a result table to the
|
|
|
1769 ** pointer given in its 3rd parameter.
|
|
|
1770 **
|
|
|
1771 ** After the application has finished with the result from sqlite3_get_table(),
|
|
|
1772 ** it should pass the result table pointer to sqlite3_free_table() in order to
|
|
|
1773 ** release the memory that was malloced. Because of the way the
|
|
|
1774 ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
|
|
|
1775 ** function must not try to call [sqlite3_free()] directly. Only
|
|
|
1776 ** [sqlite3_free_table()] is able to release the memory properly and safely.
|
|
|
1777 **
|
|
|
1778 ** ^(The sqlite3_get_table() interface is implemented as a wrapper around
|
|
|
1779 ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
|
|
|
1780 ** to any internal data structures of SQLite. It uses only the public
|
|
|
1781 ** interface defined here. As a consequence, errors that occur in the
|
|
|
1782 ** wrapper layer outside of the internal [sqlite3_exec()] call are not
|
|
|
1783 ** reflected in subsequent calls to [sqlite3_errcode()] or
|
|
|
1784 ** [sqlite3_errmsg()].)^
|
|
|
1785 */
|
|
|
1786 SQLITE_API int sqlite3_get_table(
|
|
|
1787 sqlite3 *db, /* An open database */
|
|
|
1788 const char *zSql, /* SQL to be evaluated */
|
|
|
1789 char ***pazResult, /* Results of the query */
|
|
|
1790 int *pnRow, /* Number of result rows written here */
|
|
|
1791 int *pnColumn, /* Number of result columns written here */
|
|
|
1792 char **pzErrmsg /* Error msg written here */
|
|
|
1793 );
|
|
|
1794 SQLITE_API void sqlite3_free_table(char **result);
|
|
|
1795
|
|
|
1796 /*
|
|
|
1797 ** CAPI3REF: Formatted String Printing Functions
|
|
|
1798 **
|
|
|
1799 ** These routines are work-alikes of the "printf()" family of functions
|
|
|
1800 ** from the standard C library.
|
|
|
1801 **
|
|
|
1802 ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
|
|
|
1803 ** results into memory obtained from [sqlite3_malloc()].
|
|
|
1804 ** The strings returned by these two routines should be
|
|
|
1805 ** released by [sqlite3_free()]. ^Both routines return a
|
|
|
1806 ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
|
|
|
1807 ** memory to hold the resulting string.
|
|
|
1808 **
|
|
|
1809 ** ^(In sqlite3_snprintf() routine is similar to "snprintf()" from
|
|
|
1810 ** the standard C library. The result is written into the
|
|
|
1811 ** buffer supplied as the second parameter whose size is given by
|
|
|
1812 ** the first parameter. Note that the order of the
|
|
|
1813 ** first two parameters is reversed from snprintf().)^ This is an
|
|
|
1814 ** historical accident that cannot be fixed without breaking
|
|
|
1815 ** backwards compatibility. ^(Note also that sqlite3_snprintf()
|
|
|
1816 ** returns a pointer to its buffer instead of the number of
|
|
|
1817 ** characters actually written into the buffer.)^ We admit that
|
|
|
1818 ** the number of characters written would be a more useful return
|
|
|
1819 ** value but we cannot change the implementation of sqlite3_snprintf()
|
|
|
1820 ** now without breaking compatibility.
|
|
|
1821 **
|
|
|
1822 ** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
|
|
|
1823 ** guarantees that the buffer is always zero-terminated. ^The first
|
|
|
1824 ** parameter "n" is the total size of the buffer, including space for
|
|
|
1825 ** the zero terminator. So the longest string that can be completely
|
|
|
1826 ** written will be n-1 characters.
|
|
|
1827 **
|
|
|
1828 ** These routines all implement some additional formatting
|
|
|
1829 ** options that are useful for constructing SQL statements.
|
|
|
1830 ** All of the usual printf() formatting options apply. In addition, there
|
|
|
1831 ** is are "%q", "%Q", and "%z" options.
|
|
|
1832 **
|
|
|
1833 ** ^(The %q option works like %s in that it substitutes a null-terminated
|
|
|
1834 ** string from the argument list. But %q also doubles every '\'' character.
|
|
|
1835 ** %q is designed for use inside a string literal.)^ By doubling each '\''
|
|
|
1836 ** character it escapes that character and allows it to be inserted into
|
|
|
1837 ** the string.
|
|
|
1838 **
|
|
|
1839 ** For example, assume the string variable zText contains text as follows:
|
|
|
1840 **
|
|
|
1841 ** <blockquote><pre>
|
|
|
1842 ** char *zText = "It's a happy day!";
|
|
|
1843 ** </pre></blockquote>
|
|
|
1844 **
|
|
|
1845 ** One can use this text in an SQL statement as follows:
|
|
|
1846 **
|
|
|
1847 ** <blockquote><pre>
|
|
|
1848 ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
|
|
|
1849 ** sqlite3_exec(db, zSQL, 0, 0, 0);
|
|
|
1850 ** sqlite3_free(zSQL);
|
|
|
1851 ** </pre></blockquote>
|
|
|
1852 **
|
|
|
1853 ** Because the %q format string is used, the '\'' character in zText
|
|
|
1854 ** is escaped and the SQL generated is as follows:
|
|
|
1855 **
|
|
|
1856 ** <blockquote><pre>
|
|
|
1857 ** INSERT INTO table1 VALUES('It''s a happy day!')
|
|
|
1858 ** </pre></blockquote>
|
|
|
1859 **
|
|
|
1860 ** This is correct. Had we used %s instead of %q, the generated SQL
|
|
|
1861 ** would have looked like this:
|
|
|
1862 **
|
|
|
1863 ** <blockquote><pre>
|
|
|
1864 ** INSERT INTO table1 VALUES('It's a happy day!');
|
|
|
1865 ** </pre></blockquote>
|
|
|
1866 **
|
|
|
1867 ** This second example is an SQL syntax error. As a general rule you should
|
|
|
1868 ** always use %q instead of %s when inserting text into a string literal.
|
|
|
1869 **
|
|
|
1870 ** ^(The %Q option works like %q except it also adds single quotes around
|
|
|
1871 ** the outside of the total string. Additionally, if the parameter in the
|
|
|
1872 ** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
|
|
|
1873 ** single quotes).)^ So, for example, one could say:
|
|
|
1874 **
|
|
|
1875 ** <blockquote><pre>
|
|
|
1876 ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
|
|
|
1877 ** sqlite3_exec(db, zSQL, 0, 0, 0);
|
|
|
1878 ** sqlite3_free(zSQL);
|
|
|
1879 ** </pre></blockquote>
|
|
|
1880 **
|
|
|
1881 ** The code above will render a correct SQL statement in the zSQL
|
|
|
1882 ** variable even if the zText variable is a NULL pointer.
|
|
|
1883 **
|
|
|
1884 ** ^(The "%z" formatting option works like "%s" but with the
|
|
|
1885 ** addition that after the string has been read and copied into
|
|
|
1886 ** the result, [sqlite3_free()] is called on the input string.)^
|
|
|
1887 */
|
|
|
1888 SQLITE_API char *sqlite3_mprintf(const char*,...);
|
|
|
1889 SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
|
|
|
1890 SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
|
|
|
1891
|
|
|
1892 /*
|
|
|
1893 ** CAPI3REF: Memory Allocation Subsystem
|
|
|
1894 **
|
|
|
1895 ** The SQLite core uses these three routines for all of its own
|
|
|
1896 ** internal memory allocation needs. "Core" in the previous sentence
|
|
|
1897 ** does not include operating-system specific VFS implementation. The
|
|
|
1898 ** Windows VFS uses native malloc() and free() for some operations.
|
|
|
1899 **
|
|
|
1900 ** ^The sqlite3_malloc() routine returns a pointer to a block
|
|
|
1901 ** of memory at least N bytes in length, where N is the parameter.
|
|
|
1902 ** ^If sqlite3_malloc() is unable to obtain sufficient free
|
|
|
1903 ** memory, it returns a NULL pointer. ^If the parameter N to
|
|
|
1904 ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
|
|
|
1905 ** a NULL pointer.
|
|
|
1906 **
|
|
|
1907 ** ^Calling sqlite3_free() with a pointer previously returned
|
|
|
1908 ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
|
|
|
1909 ** that it might be reused. ^The sqlite3_free() routine is
|
|
|
1910 ** a no-op if is called with a NULL pointer. Passing a NULL pointer
|
|
|
1911 ** to sqlite3_free() is harmless. After being freed, memory
|
|
|
1912 ** should neither be read nor written. Even reading previously freed
|
|
|
1913 ** memory might result in a segmentation fault or other severe error.
|
|
|
1914 ** Memory corruption, a segmentation fault, or other severe error
|
|
|
1915 ** might result if sqlite3_free() is called with a non-NULL pointer that
|
|
|
1916 ** was not obtained from sqlite3_malloc() or sqlite3_realloc().
|
|
|
1917 **
|
|
|
1918 ** ^(The sqlite3_realloc() interface attempts to resize a
|
|
|
1919 ** prior memory allocation to be at least N bytes, where N is the
|
|
|
1920 ** second parameter. The memory allocation to be resized is the first
|
|
|
1921 ** parameter.)^ ^ If the first parameter to sqlite3_realloc()
|
|
|
1922 ** is a NULL pointer then its behavior is identical to calling
|
|
|
1923 ** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
|
|
|
1924 ** ^If the second parameter to sqlite3_realloc() is zero or
|
|
|
1925 ** negative then the behavior is exactly the same as calling
|
|
|
1926 ** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
|
|
|
1927 ** ^sqlite3_realloc() returns a pointer to a memory allocation
|
|
|
1928 ** of at least N bytes in size or NULL if sufficient memory is unavailable.
|
|
|
1929 ** ^If M is the size of the prior allocation, then min(N,M) bytes
|
|
|
1930 ** of the prior allocation are copied into the beginning of buffer returned
|
|
|
1931 ** by sqlite3_realloc() and the prior allocation is freed.
|
|
|
1932 ** ^If sqlite3_realloc() returns NULL, then the prior allocation
|
|
|
1933 ** is not freed.
|
|
|
1934 **
|
|
|
1935 ** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
|
|
|
1936 ** is always aligned to at least an 8 byte boundary.
|
|
|
1937 **
|
|
|
1938 ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
|
|
|
1939 ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
|
|
|
1940 ** implementation of these routines to be omitted. That capability
|
|
|
1941 ** is no longer provided. Only built-in memory allocators can be used.
|
|
|
1942 **
|
|
|
1943 ** The Windows OS interface layer calls
|
|
|
1944 ** the system malloc() and free() directly when converting
|
|
|
1945 ** filenames between the UTF-8 encoding used by SQLite
|
|
|
1946 ** and whatever filename encoding is used by the particular Windows
|
|
|
1947 ** installation. Memory allocation errors are detected, but
|
|
|
1948 ** they are reported back as [SQLITE_CANTOPEN] or
|
|
|
1949 ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
|
|
|
1950 **
|
|
|
1951 ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
|
|
|
1952 ** must be either NULL or else pointers obtained from a prior
|
|
|
1953 ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
|
|
|
1954 ** not yet been released.
|
|
|
1955 **
|
|
|
1956 ** The application must not read or write any part of
|
|
|
1957 ** a block of memory after it has been released using
|
|
|
1958 ** [sqlite3_free()] or [sqlite3_realloc()].
|
|
|
1959 */
|
|
|
1960 SQLITE_API void *sqlite3_malloc(int);
|
|
|
1961 SQLITE_API void *sqlite3_realloc(void*, int);
|
|
|
1962 SQLITE_API void sqlite3_free(void*);
|
|
|
1963
|
|
|
1964 /*
|
|
|
1965 ** CAPI3REF: Memory Allocator Statistics
|
|
|
1966 **
|
|
|
1967 ** SQLite provides these two interfaces for reporting on the status
|
|
|
1968 ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
|
|
|
1969 ** routines, which form the built-in memory allocation subsystem.
|
|
|
1970 **
|
|
|
1971 ** ^The [sqlite3_memory_used()] routine returns the number of bytes
|
|
|
1972 ** of memory currently outstanding (malloced but not freed).
|
|
|
1973 ** ^The [sqlite3_memory_highwater()] routine returns the maximum
|
|
|
1974 ** value of [sqlite3_memory_used()] since the high-water mark
|
|
|
1975 ** was last reset. ^The values returned by [sqlite3_memory_used()] and
|
|
|
1976 ** [sqlite3_memory_highwater()] include any overhead
|
|
|
1977 ** added by SQLite in its implementation of [sqlite3_malloc()],
|
|
|
1978 ** but not overhead added by the any underlying system library
|
|
|
1979 ** routines that [sqlite3_malloc()] may call.
|
|
|
1980 **
|
|
|
1981 ** ^The memory high-water mark is reset to the current value of
|
|
|
1982 ** [sqlite3_memory_used()] if and only if the parameter to
|
|
|
1983 ** [sqlite3_memory_highwater()] is true. ^The value returned
|
|
|
1984 ** by [sqlite3_memory_highwater(1)] is the high-water mark
|
|
|
1985 ** prior to the reset.
|
|
|
1986 */
|
|
|
1987 SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
|
|
|
1988 SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
|
|
|
1989
|
|
|
1990 /*
|
|
|
1991 ** CAPI3REF: Pseudo-Random Number Generator
|
|
|
1992 **
|
|
|
1993 ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
|
|
|
1994 ** select random [ROWID | ROWIDs] when inserting new records into a table that
|
|
|
1995 ** already uses the largest possible [ROWID]. The PRNG is also used for
|
|
|
1996 ** the build-in random() and randomblob() SQL functions. This interface allows
|
|
|
1997 ** applications to access the same PRNG for other purposes.
|
|
|
1998 **
|
|
|
1999 ** ^A call to this routine stores N bytes of randomness into buffer P.
|
|
|
2000 **
|
|
|
2001 ** ^The first time this routine is invoked (either internally or by
|
|
|
2002 ** the application) the PRNG is seeded using randomness obtained
|
|
|
2003 ** from the xRandomness method of the default [sqlite3_vfs] object.
|
|
|
2004 ** ^On all subsequent invocations, the pseudo-randomness is generated
|
|
|
2005 ** internally and without recourse to the [sqlite3_vfs] xRandomness
|
|
|
2006 ** method.
|
|
|
2007 */
|
|
|
2008 SQLITE_API void sqlite3_randomness(int N, void *P);
|
|
|
2009
|
|
|
2010 /*
|
|
|
2011 ** CAPI3REF: Compile-Time Authorization Callbacks
|
|
|
2012 **
|
|
|
2013 ** ^This routine registers a authorizer callback with a particular
|
|
|
2014 ** [database connection], supplied in the first argument.
|
|
|
2015 ** ^The authorizer callback is invoked as SQL statements are being compiled
|
|
|
2016 ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
|
|
|
2017 ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various
|
|
|
2018 ** points during the compilation process, as logic is being created
|
|
|
2019 ** to perform various actions, the authorizer callback is invoked to
|
|
|
2020 ** see if those actions are allowed. ^The authorizer callback should
|
|
|
2021 ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
|
|
|
2022 ** specific action but allow the SQL statement to continue to be
|
|
|
2023 ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
|
|
|
2024 ** rejected with an error. ^If the authorizer callback returns
|
|
|
2025 ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
|
|
|
2026 ** then the [sqlite3_prepare_v2()] or equivalent call that triggered
|
|
|
2027 ** the authorizer will fail with an error message.
|
|
|
2028 **
|
|
|
2029 ** When the callback returns [SQLITE_OK], that means the operation
|
|
|
2030 ** requested is ok. ^When the callback returns [SQLITE_DENY], the
|
|
|
2031 ** [sqlite3_prepare_v2()] or equivalent call that triggered the
|
|
|
2032 ** authorizer will fail with an error message explaining that
|
|
|
2033 ** access is denied.
|
|
|
2034 **
|
|
|
2035 ** ^The first parameter to the authorizer callback is a copy of the third
|
|
|
2036 ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
|
|
|
2037 ** to the callback is an integer [SQLITE_COPY | action code] that specifies
|
|
|
2038 ** the particular action to be authorized. ^The third through sixth parameters
|
|
|
2039 ** to the callback are zero-terminated strings that contain additional
|
|
|
2040 ** details about the action to be authorized.
|
|
|
2041 **
|
|
|
2042 ** ^If the action code is [SQLITE_READ]
|
|
|
2043 ** and the callback returns [SQLITE_IGNORE] then the
|
|
|
2044 ** [prepared statement] statement is constructed to substitute
|
|
|
2045 ** a NULL value in place of the table column that would have
|
|
|
2046 ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
|
|
|
2047 ** return can be used to deny an untrusted user access to individual
|
|
|
2048 ** columns of a table.
|
|
|
2049 ** ^If the action code is [SQLITE_DELETE] and the callback returns
|
|
|
2050 ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
|
|
|
2051 ** [truncate optimization] is disabled and all rows are deleted individually.
|
|
|
2052 **
|
|
|
2053 ** An authorizer is used when [sqlite3_prepare | preparing]
|
|
|
2054 ** SQL statements from an untrusted source, to ensure that the SQL statements
|
|
|
2055 ** do not try to access data they are not allowed to see, or that they do not
|
|
|
2056 ** try to execute malicious statements that damage the database. For
|
|
|
2057 ** example, an application may allow a user to enter arbitrary
|
|
|
2058 ** SQL queries for evaluation by a database. But the application does
|
|
|
2059 ** not want the user to be able to make arbitrary changes to the
|
|
|
2060 ** database. An authorizer could then be put in place while the
|
|
|
2061 ** user-entered SQL is being [sqlite3_prepare | prepared] that
|
|
|
2062 ** disallows everything except [SELECT] statements.
|
|
|
2063 **
|
|
|
2064 ** Applications that need to process SQL from untrusted sources
|
|
|
2065 ** might also consider lowering resource limits using [sqlite3_limit()]
|
|
|
2066 ** and limiting database size using the [max_page_count] [PRAGMA]
|
|
|
2067 ** in addition to using an authorizer.
|
|
|
2068 **
|
|
|
2069 ** ^(Only a single authorizer can be in place on a database connection
|
|
|
2070 ** at a time. Each call to sqlite3_set_authorizer overrides the
|
|
|
2071 ** previous call.)^ ^Disable the authorizer by installing a NULL callback.
|
|
|
2072 ** The authorizer is disabled by default.
|
|
|
2073 **
|
|
|
2074 ** The authorizer callback must not do anything that will modify
|
|
|
2075 ** the database connection that invoked the authorizer callback.
|
|
|
2076 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
|
|
|
2077 ** database connections for the meaning of "modify" in this paragraph.
|
|
|
2078 **
|
|
|
2079 ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
|
|
|
2080 ** statement might be re-prepared during [sqlite3_step()] due to a
|
|
|
2081 ** schema change. Hence, the application should ensure that the
|
|
|
2082 ** correct authorizer callback remains in place during the [sqlite3_step()].
|
|
|
2083 **
|
|
|
2084 ** ^Note that the authorizer callback is invoked only during
|
|
|
2085 ** [sqlite3_prepare()] or its variants. Authorization is not
|
|
|
2086 ** performed during statement evaluation in [sqlite3_step()], unless
|
|
|
2087 ** as stated in the previous paragraph, sqlite3_step() invokes
|
|
|
2088 ** sqlite3_prepare_v2() to reprepare a statement after a schema change.
|
|
|
2089 */
|
|
|
2090 SQLITE_API int sqlite3_set_authorizer(
|
|
|
2091 sqlite3*,
|
|
|
2092 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
|
|
|
2093 void *pUserData
|
|
|
2094 );
|
|
|
2095
|
|
|
2096 /*
|
|
|
2097 ** CAPI3REF: Authorizer Return Codes
|
|
|
2098 **
|
|
|
2099 ** The [sqlite3_set_authorizer | authorizer callback function] must
|
|
|
2100 ** return either [SQLITE_OK] or one of these two constants in order
|
|
|
2101 ** to signal SQLite whether or not the action is permitted. See the
|
|
|
2102 ** [sqlite3_set_authorizer | authorizer documentation] for additional
|
|
|
2103 ** information.
|
|
|
2104 */
|
|
|
2105 #define SQLITE_DENY 1 /* Abort the SQL statement with an error */
|
|
|
2106 #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
|
|
|
2107
|
|
|
2108 /*
|
|
|
2109 ** CAPI3REF: Authorizer Action Codes
|
|
|
2110 **
|
|
|
2111 ** The [sqlite3_set_authorizer()] interface registers a callback function
|
|
|
2112 ** that is invoked to authorize certain SQL statement actions. The
|
|
|
2113 ** second parameter to the callback is an integer code that specifies
|
|
|
2114 ** what action is being authorized. These are the integer action codes that
|
|
|
2115 ** the authorizer callback may be passed.
|
|
|
2116 **
|
|
|
2117 ** These action code values signify what kind of operation is to be
|
|
|
2118 ** authorized. The 3rd and 4th parameters to the authorization
|
|
|
2119 ** callback function will be parameters or NULL depending on which of these
|
|
|
2120 ** codes is used as the second parameter. ^(The 5th parameter to the
|
|
|
2121 ** authorizer callback is the name of the database ("main", "temp",
|
|
|
2122 ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
|
|
|
2123 ** is the name of the inner-most trigger or view that is responsible for
|
|
|
2124 ** the access attempt or NULL if this access attempt is directly from
|
|
|
2125 ** top-level SQL code.
|
|
|
2126 */
|
|
|
2127 /******************************************* 3rd ************ 4th ***********/
|
|
|
2128 #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
|
|
|
2129 #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
|
|
|
2130 #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
|
|
|
2131 #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
|
|
|
2132 #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
|
|
|
2133 #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
|
|
|
2134 #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
|
|
|
2135 #define SQLITE_CREATE_VIEW 8 /* View Name NULL */
|
|
|
2136 #define SQLITE_DELETE 9 /* Table Name NULL */
|
|
|
2137 #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
|
|
|
2138 #define SQLITE_DROP_TABLE 11 /* Table Name NULL */
|
|
|
2139 #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
|
|
|
2140 #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
|
|
|
2141 #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
|
|
|
2142 #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
|
|
|
2143 #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
|
|
|
2144 #define SQLITE_DROP_VIEW 17 /* View Name NULL */
|
|
|
2145 #define SQLITE_INSERT 18 /* Table Name NULL */
|
|
|
2146 #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
|
|
|
2147 #define SQLITE_READ 20 /* Table Name Column Name */
|
|
|
2148 #define SQLITE_SELECT 21 /* NULL NULL */
|
|
|
2149 #define SQLITE_TRANSACTION 22 /* Operation NULL */
|
|
|
2150 #define SQLITE_UPDATE 23 /* Table Name Column Name */
|
|
|
2151 #define SQLITE_ATTACH 24 /* Filename NULL */
|
|
|
2152 #define SQLITE_DETACH 25 /* Database Name NULL */
|
|
|
2153 #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
|
|
|
2154 #define SQLITE_REINDEX 27 /* Index Name NULL */
|
|
|
2155 #define SQLITE_ANALYZE 28 /* Table Name NULL */
|
|
|
2156 #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
|
|
|
2157 #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
|
|
|
2158 #define SQLITE_FUNCTION 31 /* NULL Function Name */
|
|
|
2159 #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
|
|
|
2160 #define SQLITE_COPY 0 /* No longer used */
|
|
|
2161
|
|
|
2162 /*
|
|
|
2163 ** CAPI3REF: Tracing And Profiling Functions
|
|
|
2164 **
|
|
|
2165 ** These routines register callback functions that can be used for
|
|
|
2166 ** tracing and profiling the execution of SQL statements.
|
|
|
2167 **
|
|
|
2168 ** ^The callback function registered by sqlite3_trace() is invoked at
|
|
|
2169 ** various times when an SQL statement is being run by [sqlite3_step()].
|
|
|
2170 ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
|
|
|
2171 ** SQL statement text as the statement first begins executing.
|
|
|
2172 ** ^(Additional sqlite3_trace() callbacks might occur
|
|
|
2173 ** as each triggered subprogram is entered. The callbacks for triggers
|
|
|
2174 ** contain a UTF-8 SQL comment that identifies the trigger.)^
|
|
|
2175 **
|
|
|
2176 ** ^The callback function registered by sqlite3_profile() is invoked
|
|
|
2177 ** as each SQL statement finishes. ^The profile callback contains
|
|
|
2178 ** the original statement text and an estimate of wall-clock time
|
|
|
2179 ** of how long that statement took to run.
|
|
|
2180 */
|
|
|
2181 SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
|
|
|
2182 SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
|
|
|
2183 void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
|
|
|
2184
|
|
|
2185 /*
|
|
|
2186 ** CAPI3REF: Query Progress Callbacks
|
|
|
2187 **
|
|
|
2188 ** ^This routine configures a callback function - the
|
|
|
2189 ** progress callback - that is invoked periodically during long
|
|
|
2190 ** running calls to [sqlite3_exec()], [sqlite3_step()] and
|
|
|
2191 ** [sqlite3_get_table()]. An example use for this
|
|
|
2192 ** interface is to keep a GUI updated during a large query.
|
|
|
2193 **
|
|
|
2194 ** ^If the progress callback returns non-zero, the operation is
|
|
|
2195 ** interrupted. This feature can be used to implement a
|
|
|
2196 ** "Cancel" button on a GUI progress dialog box.
|
|
|
2197 **
|
|
|
2198 ** The progress handler must not do anything that will modify
|
|
|
2199 ** the database connection that invoked the progress handler.
|
|
|
2200 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
|
|
|
2201 ** database connections for the meaning of "modify" in this paragraph.
|
|
|
2202 **
|
|
|
2203 */
|
|
|
2204 SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
|
|
|
2205
|
|
|
2206 /*
|
|
|
2207 ** CAPI3REF: Opening A New Database Connection
|
|
|
2208 **
|
|
|
2209 ** ^These routines open an SQLite database file whose name is given by the
|
|
|
2210 ** filename argument. ^The filename argument is interpreted as UTF-8 for
|
|
|
2211 ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
|
|
|
2212 ** order for sqlite3_open16(). ^(A [database connection] handle is usually
|
|
|
2213 ** returned in *ppDb, even if an error occurs. The only exception is that
|
|
|
2214 ** if SQLite is unable to allocate memory to hold the [sqlite3] object,
|
|
|
2215 ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
|
|
|
2216 ** object.)^ ^(If the database is opened (and/or created) successfully, then
|
|
|
2217 ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
|
|
|
2218 ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
|
|
|
2219 ** an English language description of the error following a failure of any
|
|
|
2220 ** of the sqlite3_open() routines.
|
|
|
2221 **
|
|
|
2222 ** ^The default encoding for the database will be UTF-8 if
|
|
|
2223 ** sqlite3_open() or sqlite3_open_v2() is called and
|
|
|
2224 ** UTF-16 in the native byte order if sqlite3_open16() is used.
|
|
|
2225 **
|
|
|
2226 ** Whether or not an error occurs when it is opened, resources
|
|
|
2227 ** associated with the [database connection] handle should be released by
|
|
|
2228 ** passing it to [sqlite3_close()] when it is no longer required.
|
|
|
2229 **
|
|
|
2230 ** The sqlite3_open_v2() interface works like sqlite3_open()
|
|
|
2231 ** except that it accepts two additional parameters for additional control
|
|
|
2232 ** over the new database connection. ^(The flags parameter to
|
|
|
2233 ** sqlite3_open_v2() can take one of
|
|
|
2234 ** the following three values, optionally combined with the
|
|
|
2235 ** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
|
|
|
2236 ** and/or [SQLITE_OPEN_PRIVATECACHE] flags:)^
|
|
|
2237 **
|
|
|
2238 ** <dl>
|
|
|
2239 ** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
|
|
|
2240 ** <dd>The database is opened in read-only mode. If the database does not
|
|
|
2241 ** already exist, an error is returned.</dd>)^
|
|
|
2242 **
|
|
|
2243 ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
|
|
|
2244 ** <dd>The database is opened for reading and writing if possible, or reading
|
|
|
2245 ** only if the file is write protected by the operating system. In either
|
|
|
2246 ** case the database must already exist, otherwise an error is returned.</dd>)^
|
|
|
2247 **
|
|
|
2248 ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
|
|
|
2249 ** <dd>The database is opened for reading and writing, and is creates it if
|
|
|
2250 ** it does not already exist. This is the behavior that is always used for
|
|
|
2251 ** sqlite3_open() and sqlite3_open16().</dd>)^
|
|
|
2252 ** </dl>
|
|
|
2253 **
|
|
|
2254 ** If the 3rd parameter to sqlite3_open_v2() is not one of the
|
|
|
2255 ** combinations shown above or one of the combinations shown above combined
|
|
|
2256 ** with the [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX],
|
|
|
2257 ** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_SHAREDCACHE] flags,
|
|
|
2258 ** then the behavior is undefined.
|
|
|
2259 **
|
|
|
2260 ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
|
|
|
2261 ** opens in the multi-thread [threading mode] as long as the single-thread
|
|
|
2262 ** mode has not been set at compile-time or start-time. ^If the
|
|
|
2263 ** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
|
|
|
2264 ** in the serialized [threading mode] unless single-thread was
|
|
|
2265 ** previously selected at compile-time or start-time.
|
|
|
2266 ** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
|
|
|
2267 ** eligible to use [shared cache mode], regardless of whether or not shared
|
|
|
2268 ** cache is enabled using [sqlite3_enable_shared_cache()]. ^The
|
|
|
2269 ** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
|
|
|
2270 ** participate in [shared cache mode] even if it is enabled.
|
|
|
2271 **
|
|
|
2272 ** ^If the filename is ":memory:", then a private, temporary in-memory database
|
|
|
2273 ** is created for the connection. ^This in-memory database will vanish when
|
|
|
2274 ** the database connection is closed. Future versions of SQLite might
|
|
|
2275 ** make use of additional special filenames that begin with the ":" character.
|
|
|
2276 ** It is recommended that when a database filename actually does begin with
|
|
|
2277 ** a ":" character you should prefix the filename with a pathname such as
|
|
|
2278 ** "./" to avoid ambiguity.
|
|
|
2279 **
|
|
|
2280 ** ^If the filename is an empty string, then a private, temporary
|
|
|
2281 ** on-disk database will be created. ^This private database will be
|
|
|
2282 ** automatically deleted as soon as the database connection is closed.
|
|
|
2283 **
|
|
|
2284 ** ^The fourth parameter to sqlite3_open_v2() is the name of the
|
|
|
2285 ** [sqlite3_vfs] object that defines the operating system interface that
|
|
|
2286 ** the new database connection should use. ^If the fourth parameter is
|
|
|
2287 ** a NULL pointer then the default [sqlite3_vfs] object is used.
|
|
|
2288 **
|
|
|
2289 ** <b>Note to Windows users:</b> The encoding used for the filename argument
|
|
|
2290 ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
|
|
|
2291 ** codepage is currently defined. Filenames containing international
|
|
|
2292 ** characters must be converted to UTF-8 prior to passing them into
|
|
|
2293 ** sqlite3_open() or sqlite3_open_v2().
|
|
|
2294 */
|
|
|
2295 SQLITE_API int sqlite3_open(
|
|
|
2296 const char *filename, /* Database filename (UTF-8) */
|
|
|
2297 sqlite3 **ppDb /* OUT: SQLite db handle */
|
|
|
2298 );
|
|
|
2299 SQLITE_API int sqlite3_open16(
|
|
|
2300 const void *filename, /* Database filename (UTF-16) */
|
|
|
2301 sqlite3 **ppDb /* OUT: SQLite db handle */
|
|
|
2302 );
|
|
|
2303 SQLITE_API int sqlite3_open_v2(
|
|
|
2304 const char *filename, /* Database filename (UTF-8) */
|
|
|
2305 sqlite3 **ppDb, /* OUT: SQLite db handle */
|
|
|
2306 int flags, /* Flags */
|
|
|
2307 const char *zVfs /* Name of VFS module to use */
|
|
|
2308 );
|
|
|
2309
|
|
|
2310 /*
|
|
|
2311 ** CAPI3REF: Error Codes And Messages
|
|
|
2312 **
|
|
|
2313 ** ^The sqlite3_errcode() interface returns the numeric [result code] or
|
|
|
2314 ** [extended result code] for the most recent failed sqlite3_* API call
|
|
|
2315 ** associated with a [database connection]. If a prior API call failed
|
|
|
2316 ** but the most recent API call succeeded, the return value from
|
|
|
2317 ** sqlite3_errcode() is undefined. ^The sqlite3_extended_errcode()
|
|
|
2318 ** interface is the same except that it always returns the
|
|
|
2319 ** [extended result code] even when extended result codes are
|
|
|
2320 ** disabled.
|
|
|
2321 **
|
|
|
2322 ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
|
|
|
2323 ** text that describes the error, as either UTF-8 or UTF-16 respectively.
|
|
|
2324 ** ^(Memory to hold the error message string is managed internally.
|
|
|
2325 ** The application does not need to worry about freeing the result.
|
|
|
2326 ** However, the error string might be overwritten or deallocated by
|
|
|
2327 ** subsequent calls to other SQLite interface functions.)^
|
|
|
2328 **
|
|
|
2329 ** When the serialized [threading mode] is in use, it might be the
|
|
|
2330 ** case that a second error occurs on a separate thread in between
|
|
|
2331 ** the time of the first error and the call to these interfaces.
|
|
|
2332 ** When that happens, the second error will be reported since these
|
|
|
2333 ** interfaces always report the most recent result. To avoid
|
|
|
2334 ** this, each thread can obtain exclusive use of the [database connection] D
|
|
|
2335 ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
|
|
|
2336 ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
|
|
|
2337 ** all calls to the interfaces listed here are completed.
|
|
|
2338 **
|
|
|
2339 ** If an interface fails with SQLITE_MISUSE, that means the interface
|
|
|
2340 ** was invoked incorrectly by the application. In that case, the
|
|
|
2341 ** error code and message may or may not be set.
|
|
|
2342 */
|
|
|
2343 SQLITE_API int sqlite3_errcode(sqlite3 *db);
|
|
|
2344 SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
|
|
|
2345 SQLITE_API const char *sqlite3_errmsg(sqlite3*);
|
|
|
2346 SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
|
|
|
2347
|
|
|
2348 /*
|
|
|
2349 ** CAPI3REF: SQL Statement Object
|
|
|
2350 ** KEYWORDS: {prepared statement} {prepared statements}
|
|
|
2351 **
|
|
|
2352 ** An instance of this object represents a single SQL statement.
|
|
|
2353 ** This object is variously known as a "prepared statement" or a
|
|
|
2354 ** "compiled SQL statement" or simply as a "statement".
|
|
|
2355 **
|
|
|
2356 ** The life of a statement object goes something like this:
|
|
|
2357 **
|
|
|
2358 ** <ol>
|
|
|
2359 ** <li> Create the object using [sqlite3_prepare_v2()] or a related
|
|
|
2360 ** function.
|
|
|
2361 ** <li> Bind values to [host parameters] using the sqlite3_bind_*()
|
|
|
2362 ** interfaces.
|
|
|
2363 ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
|
|
|
2364 ** <li> Reset the statement using [sqlite3_reset()] then go back
|
|
|
2365 ** to step 2. Do this zero or more times.
|
|
|
2366 ** <li> Destroy the object using [sqlite3_finalize()].
|
|
|
2367 ** </ol>
|
|
|
2368 **
|
|
|
2369 ** Refer to documentation on individual methods above for additional
|
|
|
2370 ** information.
|
|
|
2371 */
|
|
|
2372 typedef struct sqlite3_stmt sqlite3_stmt;
|
|
|
2373
|
|
|
2374 /*
|
|
|
2375 ** CAPI3REF: Run-time Limits
|
|
|
2376 **
|
|
|
2377 ** ^(This interface allows the size of various constructs to be limited
|
|
|
2378 ** on a connection by connection basis. The first parameter is the
|
|
|
2379 ** [database connection] whose limit is to be set or queried. The
|
|
|
2380 ** second parameter is one of the [limit categories] that define a
|
|
|
2381 ** class of constructs to be size limited. The third parameter is the
|
|
|
2382 ** new limit for that construct. The function returns the old limit.)^
|
|
|
2383 **
|
|
|
2384 ** ^If the new limit is a negative number, the limit is unchanged.
|
|
|
2385 ** ^(For the limit category of SQLITE_LIMIT_XYZ there is a
|
|
|
2386 ** [limits | hard upper bound]
|
|
|
2387 ** set by a compile-time C preprocessor macro named
|
|
|
2388 ** [limits | SQLITE_MAX_XYZ].
|
|
|
2389 ** (The "_LIMIT_" in the name is changed to "_MAX_".))^
|
|
|
2390 ** ^Attempts to increase a limit above its hard upper bound are
|
|
|
2391 ** silently truncated to the hard upper bound.
|
|
|
2392 **
|
|
|
2393 ** Run-time limits are intended for use in applications that manage
|
|
|
2394 ** both their own internal database and also databases that are controlled
|
|
|
2395 ** by untrusted external sources. An example application might be a
|
|
|
2396 ** web browser that has its own databases for storing history and
|
|
|
2397 ** separate databases controlled by JavaScript applications downloaded
|
|
|
2398 ** off the Internet. The internal databases can be given the
|
|
|
2399 ** large, default limits. Databases managed by external sources can
|
|
|
2400 ** be given much smaller limits designed to prevent a denial of service
|
|
|
2401 ** attack. Developers might also want to use the [sqlite3_set_authorizer()]
|
|
|
2402 ** interface to further control untrusted SQL. The size of the database
|
|
|
2403 ** created by an untrusted script can be contained using the
|
|
|
2404 ** [max_page_count] [PRAGMA].
|
|
|
2405 **
|
|
|
2406 ** New run-time limit categories may be added in future releases.
|
|
|
2407 */
|
|
|
2408 SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
|
|
|
2409
|
|
|
2410 /*
|
|
|
2411 ** CAPI3REF: Run-Time Limit Categories
|
|
|
2412 ** KEYWORDS: {limit category} {*limit categories}
|
|
|
2413 **
|
|
|
2414 ** These constants define various performance limits
|
|
|
2415 ** that can be lowered at run-time using [sqlite3_limit()].
|
|
|
2416 ** The synopsis of the meanings of the various limits is shown below.
|
|
|
2417 ** Additional information is available at [limits | Limits in SQLite].
|
|
|
2418 **
|
|
|
2419 ** <dl>
|
|
|
2420 ** ^(<dt>SQLITE_LIMIT_LENGTH</dt>
|
|
|
2421 ** <dd>The maximum size of any string or BLOB or table row.<dd>)^
|
|
|
2422 **
|
|
|
2423 ** ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
|
|
|
2424 ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
|
|
|
2425 **
|
|
|
2426 ** ^(<dt>SQLITE_LIMIT_COLUMN</dt>
|
|
|
2427 ** <dd>The maximum number of columns in a table definition or in the
|
|
|
2428 ** result set of a [SELECT] or the maximum number of columns in an index
|
|
|
2429 ** or in an ORDER BY or GROUP BY clause.</dd>)^
|
|
|
2430 **
|
|
|
2431 ** ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
|
|
|
2432 ** <dd>The maximum depth of the parse tree on any expression.</dd>)^
|
|
|
2433 **
|
|
|
2434 ** ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
|
|
|
2435 ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
|
|
|
2436 **
|
|
|
2437 ** ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
|
|
|
2438 ** <dd>The maximum number of instructions in a virtual machine program
|
|
|
2439 ** used to implement an SQL statement.</dd>)^
|
|
|
2440 **
|
|
|
2441 ** ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
|
|
|
2442 ** <dd>The maximum number of arguments on a function.</dd>)^
|
|
|
2443 **
|
|
|
2444 ** ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
|
|
|
2445 ** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
|
|
|
2446 **
|
|
|
2447 ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
|
|
|
2448 ** <dd>The maximum length of the pattern argument to the [LIKE] or
|
|
|
2449 ** [GLOB] operators.</dd>)^
|
|
|
2450 **
|
|
|
2451 ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
|
|
|
2452 ** <dd>The maximum number of variables in an SQL statement that can
|
|
|
2453 ** be bound.</dd>)^
|
|
|
2454 **
|
|
|
2455 ** ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
|
|
|
2456 ** <dd>The maximum depth of recursion for triggers.</dd>)^
|
|
|
2457 ** </dl>
|
|
|
2458 */
|
|
|
2459 #define SQLITE_LIMIT_LENGTH 0
|
|
|
2460 #define SQLITE_LIMIT_SQL_LENGTH 1
|
|
|
2461 #define SQLITE_LIMIT_COLUMN 2
|
|
|
2462 #define SQLITE_LIMIT_EXPR_DEPTH 3
|
|
|
2463 #define SQLITE_LIMIT_COMPOUND_SELECT 4
|
|
|
2464 #define SQLITE_LIMIT_VDBE_OP 5
|
|
|
2465 #define SQLITE_LIMIT_FUNCTION_ARG 6
|
|
|
2466 #define SQLITE_LIMIT_ATTACHED 7
|
|
|
2467 #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
|
|
|
2468 #define SQLITE_LIMIT_VARIABLE_NUMBER 9
|
|
|
2469 #define SQLITE_LIMIT_TRIGGER_DEPTH 10
|
|
|
2470
|
|
|
2471 /*
|
|
|
2472 ** CAPI3REF: Compiling An SQL Statement
|
|
|
2473 ** KEYWORDS: {SQL statement compiler}
|
|
|
2474 **
|
|
|
2475 ** To execute an SQL query, it must first be compiled into a byte-code
|
|
|
2476 ** program using one of these routines.
|
|
|
2477 **
|
|
|
2478 ** The first argument, "db", is a [database connection] obtained from a
|
|
|
2479 ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
|
|
|
2480 ** [sqlite3_open16()]. The database connection must not have been closed.
|
|
|
2481 **
|
|
|
2482 ** The second argument, "zSql", is the statement to be compiled, encoded
|
|
|
2483 ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
|
|
|
2484 ** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
|
|
|
2485 ** use UTF-16.
|
|
|
2486 **
|
|
|
2487 ** ^If the nByte argument is less than zero, then zSql is read up to the
|
|
|
2488 ** first zero terminator. ^If nByte is non-negative, then it is the maximum
|
|
|
2489 ** number of bytes read from zSql. ^When nByte is non-negative, the
|
|
|
2490 ** zSql string ends at either the first '\000' or '\u0000' character or
|
|
|
2491 ** the nByte-th byte, whichever comes first. If the caller knows
|
|
|
2492 ** that the supplied string is nul-terminated, then there is a small
|
|
|
2493 ** performance advantage to be gained by passing an nByte parameter that
|
|
|
2494 ** is equal to the number of bytes in the input string <i>including</i>
|
|
|
2495 ** the nul-terminator bytes.
|
|
|
2496 **
|
|
|
2497 ** ^If pzTail is not NULL then *pzTail is made to point to the first byte
|
|
|
2498 ** past the end of the first SQL statement in zSql. These routines only
|
|
|
2499 ** compile the first statement in zSql, so *pzTail is left pointing to
|
|
|
2500 ** what remains uncompiled.
|
|
|
2501 **
|
|
|
2502 ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
|
|
|
2503 ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
|
|
|
2504 ** to NULL. ^If the input text contains no SQL (if the input is an empty
|
|
|
2505 ** string or a comment) then *ppStmt is set to NULL.
|
|
|
2506 ** The calling procedure is responsible for deleting the compiled
|
|
|
2507 ** SQL statement using [sqlite3_finalize()] after it has finished with it.
|
|
|
2508 ** ppStmt may not be NULL.
|
|
|
2509 **
|
|
|
2510 ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
|
|
|
2511 ** otherwise an [error code] is returned.
|
|
|
2512 **
|
|
|
2513 ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
|
|
|
2514 ** recommended for all new programs. The two older interfaces are retained
|
|
|
2515 ** for backwards compatibility, but their use is discouraged.
|
|
|
2516 ** ^In the "v2" interfaces, the prepared statement
|
|
|
2517 ** that is returned (the [sqlite3_stmt] object) contains a copy of the
|
|
|
2518 ** original SQL text. This causes the [sqlite3_step()] interface to
|
|
|
2519 ** behave differently in three ways:
|
|
|
2520 **
|
|
|
2521 ** <ol>
|
|
|
2522 ** <li>
|
|
|
2523 ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
|
|
|
2524 ** always used to do, [sqlite3_step()] will automatically recompile the SQL
|
|
|
2525 ** statement and try to run it again. ^If the schema has changed in
|
|
|
2526 ** a way that makes the statement no longer valid, [sqlite3_step()] will still
|
|
|
2527 ** return [SQLITE_SCHEMA]. But unlike the legacy behavior, [SQLITE_SCHEMA] is
|
|
|
2528 ** now a fatal error. Calling [sqlite3_prepare_v2()] again will not make the
|
|
|
2529 ** error go away. Note: use [sqlite3_errmsg()] to find the text
|
|
|
2530 ** of the parsing error that results in an [SQLITE_SCHEMA] return.
|
|
|
2531 ** </li>
|
|
|
2532 **
|
|
|
2533 ** <li>
|
|
|
2534 ** ^When an error occurs, [sqlite3_step()] will return one of the detailed
|
|
|
2535 ** [error codes] or [extended error codes]. ^The legacy behavior was that
|
|
|
2536 ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
|
|
|
2537 ** and the application would have to make a second call to [sqlite3_reset()]
|
|
|
2538 ** in order to find the underlying cause of the problem. With the "v2" prepare
|
|
|
2539 ** interfaces, the underlying reason for the error is returned immediately.
|
|
|
2540 ** </li>
|
|
|
2541 **
|
|
|
2542 ** <li>
|
|
|
2543 ** ^If the value of a [parameter | host parameter] in the WHERE clause might
|
|
|
2544 ** change the query plan for a statement, then the statement may be
|
|
|
2545 ** automatically recompiled (as if there had been a schema change) on the first
|
|
|
2546 ** [sqlite3_step()] call following any change to the
|
|
|
2547 ** [sqlite3_bind_text | bindings] of the [parameter].
|
|
|
2548 ** </li>
|
|
|
2549 ** </ol>
|
|
|
2550 */
|
|
|
2551 SQLITE_API int sqlite3_prepare(
|
|
|
2552 sqlite3 *db, /* Database handle */
|
|
|
2553 const char *zSql, /* SQL statement, UTF-8 encoded */
|
|
|
2554 int nByte, /* Maximum length of zSql in bytes. */
|
|
|
2555 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
|
|
|
2556 const char **pzTail /* OUT: Pointer to unused portion of zSql */
|
|
|
2557 );
|
|
|
2558 SQLITE_API int sqlite3_prepare_v2(
|
|
|
2559 sqlite3 *db, /* Database handle */
|
|
|
2560 const char *zSql, /* SQL statement, UTF-8 encoded */
|
|
|
2561 int nByte, /* Maximum length of zSql in bytes. */
|
|
|
2562 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
|
|
|
2563 const char **pzTail /* OUT: Pointer to unused portion of zSql */
|
|
|
2564 );
|
|
|
2565 SQLITE_API int sqlite3_prepare16(
|
|
|
2566 sqlite3 *db, /* Database handle */
|
|
|
2567 const void *zSql, /* SQL statement, UTF-16 encoded */
|
|
|
2568 int nByte, /* Maximum length of zSql in bytes. */
|
|
|
2569 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
|
|
|
2570 const void **pzTail /* OUT: Pointer to unused portion of zSql */
|
|
|
2571 );
|
|
|
2572 SQLITE_API int sqlite3_prepare16_v2(
|
|
|
2573 sqlite3 *db, /* Database handle */
|
|
|
2574 const void *zSql, /* SQL statement, UTF-16 encoded */
|
|
|
2575 int nByte, /* Maximum length of zSql in bytes. */
|
|
|
2576 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
|
|
|
2577 const void **pzTail /* OUT: Pointer to unused portion of zSql */
|
|
|
2578 );
|
|
|
2579
|
|
|
2580 /*
|
|
|
2581 ** CAPI3REF: Retrieving Statement SQL
|
|
|
2582 **
|
|
|
2583 ** ^This interface can be used to retrieve a saved copy of the original
|
|
|
2584 ** SQL text used to create a [prepared statement] if that statement was
|
|
|
2585 ** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
|
|
|
2586 */
|
|
|
2587 SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
|
|
|
2588
|
|
|
2589 /*
|
|
|
2590 ** CAPI3REF: Dynamically Typed Value Object
|
|
|
2591 ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
|
|
|
2592 **
|
|
|
2593 ** SQLite uses the sqlite3_value object to represent all values
|
|
|
2594 ** that can be stored in a database table. SQLite uses dynamic typing
|
|
|
2595 ** for the values it stores. ^Values stored in sqlite3_value objects
|
|
|
2596 ** can be integers, floating point values, strings, BLOBs, or NULL.
|
|
|
2597 **
|
|
|
2598 ** An sqlite3_value object may be either "protected" or "unprotected".
|
|
|
2599 ** Some interfaces require a protected sqlite3_value. Other interfaces
|
|
|
2600 ** will accept either a protected or an unprotected sqlite3_value.
|
|
|
2601 ** Every interface that accepts sqlite3_value arguments specifies
|
|
|
2602 ** whether or not it requires a protected sqlite3_value.
|
|
|
2603 **
|
|
|
2604 ** The terms "protected" and "unprotected" refer to whether or not
|
|
|
2605 ** a mutex is held. A internal mutex is held for a protected
|
|
|
2606 ** sqlite3_value object but no mutex is held for an unprotected
|
|
|
2607 ** sqlite3_value object. If SQLite is compiled to be single-threaded
|
|
|
2608 ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
|
|
|
2609 ** or if SQLite is run in one of reduced mutex modes
|
|
|
2610 ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
|
|
|
2611 ** then there is no distinction between protected and unprotected
|
|
|
2612 ** sqlite3_value objects and they can be used interchangeably. However,
|
|
|
2613 ** for maximum code portability it is recommended that applications
|
|
|
2614 ** still make the distinction between between protected and unprotected
|
|
|
2615 ** sqlite3_value objects even when not strictly required.
|
|
|
2616 **
|
|
|
2617 ** ^The sqlite3_value objects that are passed as parameters into the
|
|
|
2618 ** implementation of [application-defined SQL functions] are protected.
|
|
|
2619 ** ^The sqlite3_value object returned by
|
|
|
2620 ** [sqlite3_column_value()] is unprotected.
|
|
|
2621 ** Unprotected sqlite3_value objects may only be used with
|
|
|
2622 ** [sqlite3_result_value()] and [sqlite3_bind_value()].
|
|
|
2623 ** The [sqlite3_value_blob | sqlite3_value_type()] family of
|
|
|
2624 ** interfaces require protected sqlite3_value objects.
|
|
|
2625 */
|
|
|
2626 typedef struct Mem sqlite3_value;
|
|
|
2627
|
|
|
2628 /*
|
|
|
2629 ** CAPI3REF: SQL Function Context Object
|
|
|
2630 **
|
|
|
2631 ** The context in which an SQL function executes is stored in an
|
|
|
2632 ** sqlite3_context object. ^A pointer to an sqlite3_context object
|
|
|
2633 ** is always first parameter to [application-defined SQL functions].
|
|
|
2634 ** The application-defined SQL function implementation will pass this
|
|
|
2635 ** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
|
|
|
2636 ** [sqlite3_aggregate_context()], [sqlite3_user_data()],
|
|
|
2637 ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
|
|
|
2638 ** and/or [sqlite3_set_auxdata()].
|
|
|
2639 */
|
|
|
2640 typedef struct sqlite3_context sqlite3_context;
|
|
|
2641
|
|
|
2642 /*
|
|
|
2643 ** CAPI3REF: Binding Values To Prepared Statements
|
|
|
2644 ** KEYWORDS: {host parameter} {host parameters} {host parameter name}
|
|
|
2645 ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
|
|
|
2646 **
|
|
|
2647 ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
|
|
|
2648 ** literals may be replaced by a [parameter] that matches one of following
|
|
|
2649 ** templates:
|
|
|
2650 **
|
|
|
2651 ** <ul>
|
|
|
2652 ** <li> ?
|
|
|
2653 ** <li> ?NNN
|
|
|
2654 ** <li> :VVV
|
|
|
2655 ** <li> @VVV
|
|
|
2656 ** <li> $VVV
|
|
|
2657 ** </ul>
|
|
|
2658 **
|
|
|
2659 ** In the templates above, NNN represents an integer literal,
|
|
|
2660 ** and VVV represents an alphanumeric identifer.)^ ^The values of these
|
|
|
2661 ** parameters (also called "host parameter names" or "SQL parameters")
|
|
|
2662 ** can be set using the sqlite3_bind_*() routines defined here.
|
|
|
2663 **
|
|
|
2664 ** ^The first argument to the sqlite3_bind_*() routines is always
|
|
|
2665 ** a pointer to the [sqlite3_stmt] object returned from
|
|
|
2666 ** [sqlite3_prepare_v2()] or its variants.
|
|
|
2667 **
|
|
|
2668 ** ^The second argument is the index of the SQL parameter to be set.
|
|
|
2669 ** ^The leftmost SQL parameter has an index of 1. ^When the same named
|
|
|
2670 ** SQL parameter is used more than once, second and subsequent
|
|
|
2671 ** occurrences have the same index as the first occurrence.
|
|
|
2672 ** ^The index for named parameters can be looked up using the
|
|
|
2673 ** [sqlite3_bind_parameter_index()] API if desired. ^The index
|
|
|
2674 ** for "?NNN" parameters is the value of NNN.
|
|
|
2675 ** ^The NNN value must be between 1 and the [sqlite3_limit()]
|
|
|
2676 ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
|
|
|
2677 **
|
|
|
2678 ** ^The third argument is the value to bind to the parameter.
|
|
|
2679 **
|
|
|
2680 ** ^(In those routines that have a fourth argument, its value is the
|
|
|
2681 ** number of bytes in the parameter. To be clear: the value is the
|
|
|
2682 ** number of <u>bytes</u> in the value, not the number of characters.)^
|
|
|
2683 ** ^If the fourth parameter is negative, the length of the string is
|
|
|
2684 ** the number of bytes up to the first zero terminator.
|
|
|
2685 **
|
|
|
2686 ** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
|
|
|
2687 ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
|
|
|
2688 ** string after SQLite has finished with it. ^If the fifth argument is
|
|
|
2689 ** the special value [SQLITE_STATIC], then SQLite assumes that the
|
|
|
2690 ** information is in static, unmanaged space and does not need to be freed.
|
|
|
2691 ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
|
|
|
2692 ** SQLite makes its own private copy of the data immediately, before
|
|
|
2693 ** the sqlite3_bind_*() routine returns.
|
|
|
2694 **
|
|
|
2695 ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
|
|
|
2696 ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
|
|
|
2697 ** (just an integer to hold its size) while it is being processed.
|
|
|
2698 ** Zeroblobs are intended to serve as placeholders for BLOBs whose
|
|
|
2699 ** content is later written using
|
|
|
2700 ** [sqlite3_blob_open | incremental BLOB I/O] routines.
|
|
|
2701 ** ^A negative value for the zeroblob results in a zero-length BLOB.
|
|
|
2702 **
|
|
|
2703 ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
|
|
|
2704 ** for the [prepared statement] or with a prepared statement for which
|
|
|
2705 ** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
|
|
|
2706 ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
|
|
|
2707 ** routine is passed a [prepared statement] that has been finalized, the
|
|
|
2708 ** result is undefined and probably harmful.
|
|
|
2709 **
|
|
|
2710 ** ^Bindings are not cleared by the [sqlite3_reset()] routine.
|
|
|
2711 ** ^Unbound parameters are interpreted as NULL.
|
|
|
2712 **
|
|
|
2713 ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
|
|
|
2714 ** [error code] if anything goes wrong.
|
|
|
2715 ** ^[SQLITE_RANGE] is returned if the parameter
|
|
|
2716 ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
|
|
|
2717 **
|
|
|
2718 ** See also: [sqlite3_bind_parameter_count()],
|
|
|
2719 ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
|
|
|
2720 */
|
|
|
2721 SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
|
|
|
2722 SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
|
|
|
2723 SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
|
|
|
2724 SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
|
|
|
2725 SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
|
|
|
2726 SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
|
|
|
2727 SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
|
|
|
2728 SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
|
|
|
2729 SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
|
|
|
2730
|
|
|
2731 /*
|
|
|
2732 ** CAPI3REF: Number Of SQL Parameters
|
|
|
2733 **
|
|
|
2734 ** ^This routine can be used to find the number of [SQL parameters]
|
|
|
2735 ** in a [prepared statement]. SQL parameters are tokens of the
|
|
|
2736 ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
|
|
|
2737 ** placeholders for values that are [sqlite3_bind_blob | bound]
|
|
|
2738 ** to the parameters at a later time.
|
|
|
2739 **
|
|
|
2740 ** ^(This routine actually returns the index of the largest (rightmost)
|
|
|
2741 ** parameter. For all forms except ?NNN, this will correspond to the
|
|
|
2742 ** number of unique parameters. If parameters of the ?NNN form are used,
|
|
|
2743 ** there may be gaps in the list.)^
|
|
|
2744 **
|
|
|
2745 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
|
|
|
2746 ** [sqlite3_bind_parameter_name()], and
|
|
|
2747 ** [sqlite3_bind_parameter_index()].
|
|
|
2748 */
|
|
|
2749 SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
|
|
|
2750
|
|
|
2751 /*
|
|
|
2752 ** CAPI3REF: Name Of A Host Parameter
|
|
|
2753 **
|
|
|
2754 ** ^The sqlite3_bind_parameter_name(P,N) interface returns
|
|
|
2755 ** the name of the N-th [SQL parameter] in the [prepared statement] P.
|
|
|
2756 ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
|
|
|
2757 ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
|
|
|
2758 ** respectively.
|
|
|
2759 ** In other words, the initial ":" or "$" or "@" or "?"
|
|
|
2760 ** is included as part of the name.)^
|
|
|
2761 ** ^Parameters of the form "?" without a following integer have no name
|
|
|
2762 ** and are referred to as "nameless" or "anonymous parameters".
|
|
|
2763 **
|
|
|
2764 ** ^The first host parameter has an index of 1, not 0.
|
|
|
2765 **
|
|
|
2766 ** ^If the value N is out of range or if the N-th parameter is
|
|
|
2767 ** nameless, then NULL is returned. ^The returned string is
|
|
|
2768 ** always in UTF-8 encoding even if the named parameter was
|
|
|
2769 ** originally specified as UTF-16 in [sqlite3_prepare16()] or
|
|
|
2770 ** [sqlite3_prepare16_v2()].
|
|
|
2771 **
|
|
|
2772 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
|
|
|
2773 ** [sqlite3_bind_parameter_count()], and
|
|
|
2774 ** [sqlite3_bind_parameter_index()].
|
|
|
2775 */
|
|
|
2776 SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
|
|
|
2777
|
|
|
2778 /*
|
|
|
2779 ** CAPI3REF: Index Of A Parameter With A Given Name
|
|
|
2780 **
|
|
|
2781 ** ^Return the index of an SQL parameter given its name. ^The
|
|
|
2782 ** index value returned is suitable for use as the second
|
|
|
2783 ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
|
|
|
2784 ** is returned if no matching parameter is found. ^The parameter
|
|
|
2785 ** name must be given in UTF-8 even if the original statement
|
|
|
2786 ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
|
|
|
2787 **
|
|
|
2788 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
|
|
|
2789 ** [sqlite3_bind_parameter_count()], and
|
|
|
2790 ** [sqlite3_bind_parameter_index()].
|
|
|
2791 */
|
|
|
2792 SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
|
|
|
2793
|
|
|
2794 /*
|
|
|
2795 ** CAPI3REF: Reset All Bindings On A Prepared Statement
|
|
|
2796 **
|
|
|
2797 ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
|
|
|
2798 ** the [sqlite3_bind_blob | bindings] on a [prepared statement].
|
|
|
2799 ** ^Use this routine to reset all host parameters to NULL.
|
|
|
2800 */
|
|
|
2801 SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
|
|
|
2802
|
|
|
2803 /*
|
|
|
2804 ** CAPI3REF: Number Of Columns In A Result Set
|
|
|
2805 **
|
|
|
2806 ** ^Return the number of columns in the result set returned by the
|
|
|
2807 ** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
|
|
|
2808 ** statement that does not return data (for example an [UPDATE]).
|
|
|
2809 */
|
|
|
2810 SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
|
|
|
2811
|
|
|
2812 /*
|
|
|
2813 ** CAPI3REF: Column Names In A Result Set
|
|
|
2814 **
|
|
|
2815 ** ^These routines return the name assigned to a particular column
|
|
|
2816 ** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
|
|
|
2817 ** interface returns a pointer to a zero-terminated UTF-8 string
|
|
|
2818 ** and sqlite3_column_name16() returns a pointer to a zero-terminated
|
|
|
2819 ** UTF-16 string. ^The first parameter is the [prepared statement]
|
|
|
2820 ** that implements the [SELECT] statement. ^The second parameter is the
|
|
|
2821 ** column number. ^The leftmost column is number 0.
|
|
|
2822 **
|
|
|
2823 ** ^The returned string pointer is valid until either the [prepared statement]
|
|
|
2824 ** is destroyed by [sqlite3_finalize()] or until the next call to
|
|
|
2825 ** sqlite3_column_name() or sqlite3_column_name16() on the same column.
|
|
|
2826 **
|
|
|
2827 ** ^If sqlite3_malloc() fails during the processing of either routine
|
|
|
2828 ** (for example during a conversion from UTF-8 to UTF-16) then a
|
|
|
2829 ** NULL pointer is returned.
|
|
|
2830 **
|
|
|
2831 ** ^The name of a result column is the value of the "AS" clause for
|
|
|
2832 ** that column, if there is an AS clause. If there is no AS clause
|
|
|
2833 ** then the name of the column is unspecified and may change from
|
|
|
2834 ** one release of SQLite to the next.
|
|
|
2835 */
|
|
|
2836 SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
|
|
|
2837 SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
|
|
|
2838
|
|
|
2839 /*
|
|
|
2840 ** CAPI3REF: Source Of Data In A Query Result
|
|
|
2841 **
|
|
|
2842 ** ^These routines provide a means to determine the database, table, and
|
|
|
2843 ** table column that is the origin of a particular result column in
|
|
|
2844 ** [SELECT] statement.
|
|
|
2845 ** ^The name of the database or table or column can be returned as
|
|
|
2846 ** either a UTF-8 or UTF-16 string. ^The _database_ routines return
|
|
|
2847 ** the database name, the _table_ routines return the table name, and
|
|
|
2848 ** the origin_ routines return the column name.
|
|
|
2849 ** ^The returned string is valid until the [prepared statement] is destroyed
|
|
|
2850 ** using [sqlite3_finalize()] or until the same information is requested
|
|
|
2851 ** again in a different encoding.
|
|
|
2852 **
|
|
|
2853 ** ^The names returned are the original un-aliased names of the
|
|
|
2854 ** database, table, and column.
|
|
|
2855 **
|
|
|
2856 ** ^The first argument to these interfaces is a [prepared statement].
|
|
|
2857 ** ^These functions return information about the Nth result column returned by
|
|
|
2858 ** the statement, where N is the second function argument.
|
|
|
2859 ** ^The left-most column is column 0 for these routines.
|
|
|
2860 **
|
|
|
2861 ** ^If the Nth column returned by the statement is an expression or
|
|
|
2862 ** subquery and is not a column value, then all of these functions return
|
|
|
2863 ** NULL. ^These routine might also return NULL if a memory allocation error
|
|
|
2864 ** occurs. ^Otherwise, they return the name of the attached database, table,
|
|
|
2865 ** or column that query result column was extracted from.
|
|
|
2866 **
|
|
|
2867 ** ^As with all other SQLite APIs, those whose names end with "16" return
|
|
|
2868 ** UTF-16 encoded strings and the other functions return UTF-8.
|
|
|
2869 **
|
|
|
2870 ** ^These APIs are only available if the library was compiled with the
|
|
|
2871 ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
|
|
|
2872 **
|
|
|
2873 ** If two or more threads call one or more of these routines against the same
|
|
|
2874 ** prepared statement and column at the same time then the results are
|
|
|
2875 ** undefined.
|
|
|
2876 **
|
|
|
2877 ** If two or more threads call one or more
|
|
|
2878 ** [sqlite3_column_database_name | column metadata interfaces]
|
|
|
2879 ** for the same [prepared statement] and result column
|
|
|
2880 ** at the same time then the results are undefined.
|
|
|
2881 */
|
|
|
2882 SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
|
|
|
2883 SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
|
|
|
2884 SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
|
|
|
2885 SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
|
|
|
2886 SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
|
|
|
2887 SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
|
|
|
2888
|
|
|
2889 /*
|
|
|
2890 ** CAPI3REF: Declared Datatype Of A Query Result
|
|
|
2891 **
|
|
|
2892 ** ^(The first parameter is a [prepared statement].
|
|
|
2893 ** If this statement is a [SELECT] statement and the Nth column of the
|
|
|
2894 ** returned result set of that [SELECT] is a table column (not an
|
|
|
2895 ** expression or subquery) then the declared type of the table
|
|
|
2896 ** column is returned.)^ ^If the Nth column of the result set is an
|
|
|
2897 ** expression or subquery, then a NULL pointer is returned.
|
|
|
2898 ** ^The returned string is always UTF-8 encoded.
|
|
|
2899 **
|
|
|
2900 ** ^(For example, given the database schema:
|
|
|
2901 **
|
|
|
2902 ** CREATE TABLE t1(c1 VARIANT);
|
|
|
2903 **
|
|
|
2904 ** and the following statement to be compiled:
|
|
|
2905 **
|
|
|
2906 ** SELECT c1 + 1, c1 FROM t1;
|
|
|
2907 **
|
|
|
2908 ** this routine would return the string "VARIANT" for the second result
|
|
|
2909 ** column (i==1), and a NULL pointer for the first result column (i==0).)^
|
|
|
2910 **
|
|
|
2911 ** ^SQLite uses dynamic run-time typing. ^So just because a column
|
|
|
2912 ** is declared to contain a particular type does not mean that the
|
|
|
2913 ** data stored in that column is of the declared type. SQLite is
|
|
|
2914 ** strongly typed, but the typing is dynamic not static. ^Type
|
|
|
2915 ** is associated with individual values, not with the containers
|
|
|
2916 ** used to hold those values.
|
|
|
2917 */
|
|
|
2918 SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
|
|
|
2919 SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
|
|
|
2920
|
|
|
2921 /*
|
|
|
2922 ** CAPI3REF: Evaluate An SQL Statement
|
|
|
2923 **
|
|
|
2924 ** After a [prepared statement] has been prepared using either
|
|
|
2925 ** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
|
|
|
2926 ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
|
|
|
2927 ** must be called one or more times to evaluate the statement.
|
|
|
2928 **
|
|
|
2929 ** The details of the behavior of the sqlite3_step() interface depend
|
|
|
2930 ** on whether the statement was prepared using the newer "v2" interface
|
|
|
2931 ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
|
|
|
2932 ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
|
|
|
2933 ** new "v2" interface is recommended for new applications but the legacy
|
|
|
2934 ** interface will continue to be supported.
|
|
|
2935 **
|
|
|
2936 ** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
|
|
|
2937 ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
|
|
|
2938 ** ^With the "v2" interface, any of the other [result codes] or
|
|
|
2939 ** [extended result codes] might be returned as well.
|
|
|
2940 **
|
|
|
2941 ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
|
|
|
2942 ** database locks it needs to do its job. ^If the statement is a [COMMIT]
|
|
|
2943 ** or occurs outside of an explicit transaction, then you can retry the
|
|
|
2944 ** statement. If the statement is not a [COMMIT] and occurs within a
|
|
|
2945 ** explicit transaction then you should rollback the transaction before
|
|
|
2946 ** continuing.
|
|
|
2947 **
|
|
|
2948 ** ^[SQLITE_DONE] means that the statement has finished executing
|
|
|
2949 ** successfully. sqlite3_step() should not be called again on this virtual
|
|
|
2950 ** machine without first calling [sqlite3_reset()] to reset the virtual
|
|
|
2951 ** machine back to its initial state.
|
|
|
2952 **
|
|
|
2953 ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
|
|
|
2954 ** is returned each time a new row of data is ready for processing by the
|
|
|
2955 ** caller. The values may be accessed using the [column access functions].
|
|
|
2956 ** sqlite3_step() is called again to retrieve the next row of data.
|
|
|
2957 **
|
|
|
2958 ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
|
|
|
2959 ** violation) has occurred. sqlite3_step() should not be called again on
|
|
|
2960 ** the VM. More information may be found by calling [sqlite3_errmsg()].
|
|
|
2961 ** ^With the legacy interface, a more specific error code (for example,
|
|
|
2962 ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
|
|
|
2963 ** can be obtained by calling [sqlite3_reset()] on the
|
|
|
2964 ** [prepared statement]. ^In the "v2" interface,
|
|
|
2965 ** the more specific error code is returned directly by sqlite3_step().
|
|
|
2966 **
|
|
|
2967 ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
|
|
|
2968 ** Perhaps it was called on a [prepared statement] that has
|
|
|
2969 ** already been [sqlite3_finalize | finalized] or on one that had
|
|
|
2970 ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
|
|
|
2971 ** be the case that the same database connection is being used by two or
|
|
|
2972 ** more threads at the same moment in time.
|
|
|
2973 **
|
|
|
2974 ** For all versions of SQLite up to and including 3.6.23.1, it was required
|
|
|
2975 ** after sqlite3_step() returned anything other than [SQLITE_ROW] that
|
|
|
2976 ** [sqlite3_reset()] be called before any subsequent invocation of
|
|
|
2977 ** sqlite3_step(). Failure to invoke [sqlite3_reset()] in this way would
|
|
|
2978 ** result in an [SQLITE_MISUSE] return from sqlite3_step(). But after
|
|
|
2979 ** version 3.6.23.1, sqlite3_step() began calling [sqlite3_reset()]
|
|
|
2980 ** automatically in this circumstance rather than returning [SQLITE_MISUSE].
|
|
|
2981 **
|
|
|
2982 ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
|
|
|
2983 ** API always returns a generic error code, [SQLITE_ERROR], following any
|
|
|
2984 ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
|
|
|
2985 ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
|
|
|
2986 ** specific [error codes] that better describes the error.
|
|
|
2987 ** We admit that this is a goofy design. The problem has been fixed
|
|
|
2988 ** with the "v2" interface. If you prepare all of your SQL statements
|
|
|
2989 ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
|
|
|
2990 ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
|
|
|
2991 ** then the more specific [error codes] are returned directly
|
|
|
2992 ** by sqlite3_step(). The use of the "v2" interface is recommended.
|
|
|
2993 */
|
|
|
2994 SQLITE_API int sqlite3_step(sqlite3_stmt*);
|
|
|
2995
|
|
|
2996 /*
|
|
|
2997 ** CAPI3REF: Number of columns in a result set
|
|
|
2998 **
|
|
|
2999 ** ^The sqlite3_data_count(P) the number of columns in the
|
|
|
3000 ** of the result set of [prepared statement] P.
|
|
|
3001 */
|
|
|
3002 SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
|
|
|
3003
|
|
|
3004 /*
|
|
|
3005 ** CAPI3REF: Fundamental Datatypes
|
|
|
3006 ** KEYWORDS: SQLITE_TEXT
|
|
|
3007 **
|
|
|
3008 ** ^(Every value in SQLite has one of five fundamental datatypes:
|
|
|
3009 **
|
|
|
3010 ** <ul>
|
|
|
3011 ** <li> 64-bit signed integer
|
|
|
3012 ** <li> 64-bit IEEE floating point number
|
|
|
3013 ** <li> string
|
|
|
3014 ** <li> BLOB
|
|
|
3015 ** <li> NULL
|
|
|
3016 ** </ul>)^
|
|
|
3017 **
|
|
|
3018 ** These constants are codes for each of those types.
|
|
|
3019 **
|
|
|
3020 ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
|
|
|
3021 ** for a completely different meaning. Software that links against both
|
|
|
3022 ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
|
|
|
3023 ** SQLITE_TEXT.
|
|
|
3024 */
|
|
|
3025 #define SQLITE_INTEGER 1
|
|
|
3026 #define SQLITE_FLOAT 2
|
|
|
3027 #define SQLITE_BLOB 4
|
|
|
3028 #define SQLITE_NULL 5
|
|
|
3029 #ifdef SQLITE_TEXT
|
|
|
3030 # undef SQLITE_TEXT
|
|
|
3031 #else
|
|
|
3032 # define SQLITE_TEXT 3
|
|
|
3033 #endif
|
|
|
3034 #define SQLITE3_TEXT 3
|
|
|
3035
|
|
|
3036 /*
|
|
|
3037 ** CAPI3REF: Result Values From A Query
|
|
|
3038 ** KEYWORDS: {column access functions}
|
|
|
3039 **
|
|
|
3040 ** These routines form the "result set" interface.
|
|
|
3041 **
|
|
|
3042 ** ^These routines return information about a single column of the current
|
|
|
3043 ** result row of a query. ^In every case the first argument is a pointer
|
|
|
3044 ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
|
|
|
3045 ** that was returned from [sqlite3_prepare_v2()] or one of its variants)
|
|
|
3046 ** and the second argument is the index of the column for which information
|
|
|
3047 ** should be returned. ^The leftmost column of the result set has the index 0.
|
|
|
3048 ** ^The number of columns in the result can be determined using
|
|
|
3049 ** [sqlite3_column_count()].
|
|
|
3050 **
|
|
|
3051 ** If the SQL statement does not currently point to a valid row, or if the
|
|
|
3052 ** column index is out of range, the result is undefined.
|
|
|
3053 ** These routines may only be called when the most recent call to
|
|
|
3054 ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
|
|
|
3055 ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
|
|
|
3056 ** If any of these routines are called after [sqlite3_reset()] or
|
|
|
3057 ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
|
|
|
3058 ** something other than [SQLITE_ROW], the results are undefined.
|
|
|
3059 ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
|
|
|
3060 ** are called from a different thread while any of these routines
|
|
|
3061 ** are pending, then the results are undefined.
|
|
|
3062 **
|
|
|
3063 ** ^The sqlite3_column_type() routine returns the
|
|
|
3064 ** [SQLITE_INTEGER | datatype code] for the initial data type
|
|
|
3065 ** of the result column. ^The returned value is one of [SQLITE_INTEGER],
|
|
|
3066 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
|
|
|
3067 ** returned by sqlite3_column_type() is only meaningful if no type
|
|
|
3068 ** conversions have occurred as described below. After a type conversion,
|
|
|
3069 ** the value returned by sqlite3_column_type() is undefined. Future
|
|
|
3070 ** versions of SQLite may change the behavior of sqlite3_column_type()
|
|
|
3071 ** following a type conversion.
|
|
|
3072 **
|
|
|
3073 ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
|
|
|
3074 ** routine returns the number of bytes in that BLOB or string.
|
|
|
3075 ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
|
|
|
3076 ** the string to UTF-8 and then returns the number of bytes.
|
|
|
3077 ** ^If the result is a numeric value then sqlite3_column_bytes() uses
|
|
|
3078 ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
|
|
|
3079 ** the number of bytes in that string.
|
|
|
3080 ** ^The value returned does not include the zero terminator at the end
|
|
|
3081 ** of the string. ^For clarity: the value returned is the number of
|
|
|
3082 ** bytes in the string, not the number of characters.
|
|
|
3083 **
|
|
|
3084 ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
|
|
|
3085 ** even empty strings, are always zero terminated. ^The return
|
|
|
3086 ** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
|
|
|
3087 ** pointer, possibly even a NULL pointer.
|
|
|
3088 **
|
|
|
3089 ** ^The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
|
|
|
3090 ** but leaves the result in UTF-16 in native byte order instead of UTF-8.
|
|
|
3091 ** ^The zero terminator is not included in this count.
|
|
|
3092 **
|
|
|
3093 ** ^The object returned by [sqlite3_column_value()] is an
|
|
|
3094 ** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
|
|
|
3095 ** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
|
|
|
3096 ** If the [unprotected sqlite3_value] object returned by
|
|
|
3097 ** [sqlite3_column_value()] is used in any other way, including calls
|
|
|
3098 ** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
|
|
|
3099 ** or [sqlite3_value_bytes()], then the behavior is undefined.
|
|
|
3100 **
|
|
|
3101 ** These routines attempt to convert the value where appropriate. ^For
|
|
|
3102 ** example, if the internal representation is FLOAT and a text result
|
|
|
3103 ** is requested, [sqlite3_snprintf()] is used internally to perform the
|
|
|
3104 ** conversion automatically. ^(The following table details the conversions
|
|
|
3105 ** that are applied:
|
|
|
3106 **
|
|
|
3107 ** <blockquote>
|
|
|
3108 ** <table border="1">
|
|
|
3109 ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
|
|
|
3110 **
|
|
|
3111 ** <tr><td> NULL <td> INTEGER <td> Result is 0
|
|
|
3112 ** <tr><td> NULL <td> FLOAT <td> Result is 0.0
|
|
|
3113 ** <tr><td> NULL <td> TEXT <td> Result is NULL pointer
|
|
|
3114 ** <tr><td> NULL <td> BLOB <td> Result is NULL pointer
|
|
|
3115 ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
|
|
|
3116 ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
|
|
|
3117 ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
|
|
|
3118 ** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer
|
|
|
3119 ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
|
|
|
3120 ** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT
|
|
|
3121 ** <tr><td> TEXT <td> INTEGER <td> Use atoi()
|
|
|
3122 ** <tr><td> TEXT <td> FLOAT <td> Use atof()
|
|
|
3123 ** <tr><td> TEXT <td> BLOB <td> No change
|
|
|
3124 ** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi()
|
|
|
3125 ** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof()
|
|
|
3126 ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
|
|
|
3127 ** </table>
|
|
|
3128 ** </blockquote>)^
|
|
|
3129 **
|
|
|
3130 ** The table above makes reference to standard C library functions atoi()
|
|
|
3131 ** and atof(). SQLite does not really use these functions. It has its
|
|
|
3132 ** own equivalent internal routines. The atoi() and atof() names are
|
|
|
3133 ** used in the table for brevity and because they are familiar to most
|
|
|
3134 ** C programmers.
|
|
|
3135 **
|
|
|
3136 ** ^Note that when type conversions occur, pointers returned by prior
|
|
|
3137 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
|
|
|
3138 ** sqlite3_column_text16() may be invalidated.
|
|
|
3139 ** ^(Type conversions and pointer invalidations might occur
|
|
|
3140 ** in the following cases:
|
|
|
3141 **
|
|
|
3142 ** <ul>
|
|
|
3143 ** <li> The initial content is a BLOB and sqlite3_column_text() or
|
|
|
3144 ** sqlite3_column_text16() is called. A zero-terminator might
|
|
|
3145 ** need to be added to the string.</li>
|
|
|
3146 ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
|
|
|
3147 ** sqlite3_column_text16() is called. The content must be converted
|
|
|
3148 ** to UTF-16.</li>
|
|
|
3149 ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
|
|
|
3150 ** sqlite3_column_text() is called. The content must be converted
|
|
|
3151 ** to UTF-8.</li>
|
|
|
3152 ** </ul>)^
|
|
|
3153 **
|
|
|
3154 ** ^Conversions between UTF-16be and UTF-16le are always done in place and do
|
|
|
3155 ** not invalidate a prior pointer, though of course the content of the buffer
|
|
|
3156 ** that the prior pointer points to will have been modified. Other kinds
|
|
|
3157 ** of conversion are done in place when it is possible, but sometimes they
|
|
|
3158 ** are not possible and in those cases prior pointers are invalidated.
|
|
|
3159 **
|
|
|
3160 ** ^(The safest and easiest to remember policy is to invoke these routines
|
|
|
3161 ** in one of the following ways:
|
|
|
3162 **
|
|
|
3163 ** <ul>
|
|
|
3164 ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
|
|
|
3165 ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
|
|
|
3166 ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
|
|
|
3167 ** </ul>)^
|
|
|
3168 **
|
|
|
3169 ** In other words, you should call sqlite3_column_text(),
|
|
|
3170 ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
|
|
|
3171 ** into the desired format, then invoke sqlite3_column_bytes() or
|
|
|
3172 ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
|
|
|
3173 ** to sqlite3_column_text() or sqlite3_column_blob() with calls to
|
|
|
3174 ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
|
|
|
3175 ** with calls to sqlite3_column_bytes().
|
|
|
3176 **
|
|
|
3177 ** ^The pointers returned are valid until a type conversion occurs as
|
|
|
3178 ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
|
|
|
3179 ** [sqlite3_finalize()] is called. ^The memory space used to hold strings
|
|
|
3180 ** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned
|
|
|
3181 ** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
|
|
|
3182 ** [sqlite3_free()].
|
|
|
3183 **
|
|
|
3184 ** ^(If a memory allocation error occurs during the evaluation of any
|
|
|
3185 ** of these routines, a default value is returned. The default value
|
|
|
3186 ** is either the integer 0, the floating point number 0.0, or a NULL
|
|
|
3187 ** pointer. Subsequent calls to [sqlite3_errcode()] will return
|
|
|
3188 ** [SQLITE_NOMEM].)^
|
|
|
3189 */
|
|
|
3190 SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
|
|
|
3191 SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
|
|
|
3192 SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
|
|
|
3193 SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
|
|
|
3194 SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
|
|
|
3195 SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
|
|
|
3196 SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
|
|
|
3197 SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
|
|
|
3198 SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
|
|
|
3199 SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
|
|
|
3200
|
|
|
3201 /*
|
|
|
3202 ** CAPI3REF: Destroy A Prepared Statement Object
|
|
|
3203 **
|
|
|
3204 ** ^The sqlite3_finalize() function is called to delete a [prepared statement].
|
|
|
3205 ** ^If the statement was executed successfully or not executed at all, then
|
|
|
3206 ** SQLITE_OK is returned. ^If execution of the statement failed then an
|
|
|
3207 ** [error code] or [extended error code] is returned.
|
|
|
3208 **
|
|
|
3209 ** ^This routine can be called at any point during the execution of the
|
|
|
3210 ** [prepared statement]. ^If the virtual machine has not
|
|
|
3211 ** completed execution when this routine is called, that is like
|
|
|
3212 ** encountering an error or an [sqlite3_interrupt | interrupt].
|
|
|
3213 ** ^Incomplete updates may be rolled back and transactions canceled,
|
|
|
3214 ** depending on the circumstances, and the
|
|
|
3215 ** [error code] returned will be [SQLITE_ABORT].
|
|
|
3216 */
|
|
|
3217 SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
|
|
|
3218
|
|
|
3219 /*
|
|
|
3220 ** CAPI3REF: Reset A Prepared Statement Object
|
|
|
3221 **
|
|
|
3222 ** The sqlite3_reset() function is called to reset a [prepared statement]
|
|
|
3223 ** object back to its initial state, ready to be re-executed.
|
|
|
3224 ** ^Any SQL statement variables that had values bound to them using
|
|
|
3225 ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
|
|
|
3226 ** Use [sqlite3_clear_bindings()] to reset the bindings.
|
|
|
3227 **
|
|
|
3228 ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
|
|
|
3229 ** back to the beginning of its program.
|
|
|
3230 **
|
|
|
3231 ** ^If the most recent call to [sqlite3_step(S)] for the
|
|
|
3232 ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
|
|
|
3233 ** or if [sqlite3_step(S)] has never before been called on S,
|
|
|
3234 ** then [sqlite3_reset(S)] returns [SQLITE_OK].
|
|
|
3235 **
|
|
|
3236 ** ^If the most recent call to [sqlite3_step(S)] for the
|
|
|
3237 ** [prepared statement] S indicated an error, then
|
|
|
3238 ** [sqlite3_reset(S)] returns an appropriate [error code].
|
|
|
3239 **
|
|
|
3240 ** ^The [sqlite3_reset(S)] interface does not change the values
|
|
|
3241 ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
|
|
|
3242 */
|
|
|
3243 SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
|
|
|
3244
|
|
|
3245 /*
|
|
|
3246 ** CAPI3REF: Create Or Redefine SQL Functions
|
|
|
3247 ** KEYWORDS: {function creation routines}
|
|
|
3248 ** KEYWORDS: {application-defined SQL function}
|
|
|
3249 ** KEYWORDS: {application-defined SQL functions}
|
|
|
3250 **
|
|
|
3251 ** ^These two functions (collectively known as "function creation routines")
|
|
|
3252 ** are used to add SQL functions or aggregates or to redefine the behavior
|
|
|
3253 ** of existing SQL functions or aggregates. The only difference between the
|
|
|
3254 ** two is that the second parameter, the name of the (scalar) function or
|
|
|
3255 ** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
|
|
|
3256 ** for sqlite3_create_function16().
|
|
|
3257 **
|
|
|
3258 ** ^The first parameter is the [database connection] to which the SQL
|
|
|
3259 ** function is to be added. ^If an application uses more than one database
|
|
|
3260 ** connection then application-defined SQL functions must be added
|
|
|
3261 ** to each database connection separately.
|
|
|
3262 **
|
|
|
3263 ** The second parameter is the name of the SQL function to be created or
|
|
|
3264 ** redefined. ^The length of the name is limited to 255 bytes, exclusive of
|
|
|
3265 ** the zero-terminator. Note that the name length limit is in bytes, not
|
|
|
3266 ** characters. ^Any attempt to create a function with a longer name
|
|
|
3267 ** will result in [SQLITE_ERROR] being returned.
|
|
|
3268 **
|
|
|
3269 ** ^The third parameter (nArg)
|
|
|
3270 ** is the number of arguments that the SQL function or
|
|
|
3271 ** aggregate takes. ^If this parameter is -1, then the SQL function or
|
|
|
3272 ** aggregate may take any number of arguments between 0 and the limit
|
|
|
3273 ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
|
|
|
3274 ** parameter is less than -1 or greater than 127 then the behavior is
|
|
|
3275 ** undefined.
|
|
|
3276 **
|
|
|
3277 ** The fourth parameter, eTextRep, specifies what
|
|
|
3278 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
|
|
|
3279 ** its parameters. Any SQL function implementation should be able to work
|
|
|
3280 ** work with UTF-8, UTF-16le, or UTF-16be. But some implementations may be
|
|
|
3281 ** more efficient with one encoding than another. ^An application may
|
|
|
3282 ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
|
|
|
3283 ** times with the same function but with different values of eTextRep.
|
|
|
3284 ** ^When multiple implementations of the same function are available, SQLite
|
|
|
3285 ** will pick the one that involves the least amount of data conversion.
|
|
|
3286 ** If there is only a single implementation which does not care what text
|
|
|
3287 ** encoding is used, then the fourth argument should be [SQLITE_ANY].
|
|
|
3288 **
|
|
|
3289 ** ^(The fifth parameter is an arbitrary pointer. The implementation of the
|
|
|
3290 ** function can gain access to this pointer using [sqlite3_user_data()].)^
|
|
|
3291 **
|
|
|
3292 ** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
|
|
|
3293 ** pointers to C-language functions that implement the SQL function or
|
|
|
3294 ** aggregate. ^A scalar SQL function requires an implementation of the xFunc
|
|
|
3295 ** callback only; NULL pointers should be passed as the xStep and xFinal
|
|
|
3296 ** parameters. ^An aggregate SQL function requires an implementation of xStep
|
|
|
3297 ** and xFinal and NULL should be passed for xFunc. ^To delete an existing
|
|
|
3298 ** SQL function or aggregate, pass NULL for all three function callbacks.
|
|
|
3299 **
|
|
|
3300 ** ^It is permitted to register multiple implementations of the same
|
|
|
3301 ** functions with the same name but with either differing numbers of
|
|
|
3302 ** arguments or differing preferred text encodings. ^SQLite will use
|
|
|
3303 ** the implementation that most closely matches the way in which the
|
|
|
3304 ** SQL function is used. ^A function implementation with a non-negative
|
|
|
3305 ** nArg parameter is a better match than a function implementation with
|
|
|
3306 ** a negative nArg. ^A function where the preferred text encoding
|
|
|
3307 ** matches the database encoding is a better
|
|
|
3308 ** match than a function where the encoding is different.
|
|
|
3309 ** ^A function where the encoding difference is between UTF16le and UTF16be
|
|
|
3310 ** is a closer match than a function where the encoding difference is
|
|
|
3311 ** between UTF8 and UTF16.
|
|
|
3312 **
|
|
|
3313 ** ^Built-in functions may be overloaded by new application-defined functions.
|
|
|
3314 ** ^The first application-defined function with a given name overrides all
|
|
|
3315 ** built-in functions in the same [database connection] with the same name.
|
|
|
3316 ** ^Subsequent application-defined functions of the same name only override
|
|
|
3317 ** prior application-defined functions that are an exact match for the
|
|
|
3318 ** number of parameters and preferred encoding.
|
|
|
3319 **
|
|
|
3320 ** ^An application-defined function is permitted to call other
|
|
|
3321 ** SQLite interfaces. However, such calls must not
|
|
|
3322 ** close the database connection nor finalize or reset the prepared
|
|
|
3323 ** statement in which the function is running.
|
|
|
3324 */
|
|
|
3325 SQLITE_API int sqlite3_create_function(
|
|
|
3326 sqlite3 *db,
|
|
|
3327 const char *zFunctionName,
|
|
|
3328 int nArg,
|
|
|
3329 int eTextRep,
|
|
|
3330 void *pApp,
|
|
|
3331 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
|
|
|
3332 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
|
|
|
3333 void (*xFinal)(sqlite3_context*)
|
|
|
3334 );
|
|
|
3335 SQLITE_API int sqlite3_create_function16(
|
|
|
3336 sqlite3 *db,
|
|
|
3337 const void *zFunctionName,
|
|
|
3338 int nArg,
|
|
|
3339 int eTextRep,
|
|
|
3340 void *pApp,
|
|
|
3341 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
|
|
|
3342 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
|
|
|
3343 void (*xFinal)(sqlite3_context*)
|
|
|
3344 );
|
|
|
3345
|
|
|
3346 /*
|
|
|
3347 ** CAPI3REF: Text Encodings
|
|
|
3348 **
|
|
|
3349 ** These constant define integer codes that represent the various
|
|
|
3350 ** text encodings supported by SQLite.
|
|
|
3351 */
|
|
|
3352 #define SQLITE_UTF8 1
|
|
|
3353 #define SQLITE_UTF16LE 2
|
|
|
3354 #define SQLITE_UTF16BE 3
|
|
|
3355 #define SQLITE_UTF16 4 /* Use native byte order */
|
|
|
3356 #define SQLITE_ANY 5 /* sqlite3_create_function only */
|
|
|
3357 #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
|
|
|
3358
|
|
|
3359 /*
|
|
|
3360 ** CAPI3REF: Deprecated Functions
|
|
|
3361 ** DEPRECATED
|
|
|
3362 **
|
|
|
3363 ** These functions are [deprecated]. In order to maintain
|
|
|
3364 ** backwards compatibility with older code, these functions continue
|
|
|
3365 ** to be supported. However, new applications should avoid
|
|
|
3366 ** the use of these functions. To help encourage people to avoid
|
|
|
3367 ** using these functions, we are not going to tell you what they do.
|
|
|
3368 */
|
|
|
3369 #ifndef SQLITE_OMIT_DEPRECATED
|
|
|
3370 SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
|
|
|
3371 SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
|
|
|
3372 SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
|
|
|
3373 SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
|
|
|
3374 SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
|
|
|
3375 SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
|
|
|
3376 #endif
|
|
|
3377
|
|
|
3378 /*
|
|
|
3379 ** CAPI3REF: Obtaining SQL Function Parameter Values
|
|
|
3380 **
|
|
|
3381 ** The C-language implementation of SQL functions and aggregates uses
|
|
|
3382 ** this set of interface routines to access the parameter values on
|
|
|
3383 ** the function or aggregate.
|
|
|
3384 **
|
|
|
3385 ** The xFunc (for scalar functions) or xStep (for aggregates) parameters
|
|
|
3386 ** to [sqlite3_create_function()] and [sqlite3_create_function16()]
|
|
|
3387 ** define callbacks that implement the SQL functions and aggregates.
|
|
|
3388 ** The 4th parameter to these callbacks is an array of pointers to
|
|
|
3389 ** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
|
|
|
3390 ** each parameter to the SQL function. These routines are used to
|
|
|
3391 ** extract values from the [sqlite3_value] objects.
|
|
|
3392 **
|
|
|
3393 ** These routines work only with [protected sqlite3_value] objects.
|
|
|
3394 ** Any attempt to use these routines on an [unprotected sqlite3_value]
|
|
|
3395 ** object results in undefined behavior.
|
|
|
3396 **
|
|
|
3397 ** ^These routines work just like the corresponding [column access functions]
|
|
|
3398 ** except that these routines take a single [protected sqlite3_value] object
|
|
|
3399 ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
|
|
|
3400 **
|
|
|
3401 ** ^The sqlite3_value_text16() interface extracts a UTF-16 string
|
|
|
3402 ** in the native byte-order of the host machine. ^The
|
|
|
3403 ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
|
|
|
3404 ** extract UTF-16 strings as big-endian and little-endian respectively.
|
|
|
3405 **
|
|
|
3406 ** ^(The sqlite3_value_numeric_type() interface attempts to apply
|
|
|
3407 ** numeric affinity to the value. This means that an attempt is
|
|
|
3408 ** made to convert the value to an integer or floating point. If
|
|
|
3409 ** such a conversion is possible without loss of information (in other
|
|
|
3410 ** words, if the value is a string that looks like a number)
|
|
|
3411 ** then the conversion is performed. Otherwise no conversion occurs.
|
|
|
3412 ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
|
|
|
3413 **
|
|
|
3414 ** Please pay particular attention to the fact that the pointer returned
|
|
|
3415 ** from [sqlite3_value_blob()], [sqlite3_value_text()], or
|
|
|
3416 ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
|
|
|
3417 ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
|
|
|
3418 ** or [sqlite3_value_text16()].
|
|
|
3419 **
|
|
|
3420 ** These routines must be called from the same thread as
|
|
|
3421 ** the SQL function that supplied the [sqlite3_value*] parameters.
|
|
|
3422 */
|
|
|
3423 SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
|
|
|
3424 SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
|
|
|
3425 SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
|
|
|
3426 SQLITE_API double sqlite3_value_double(sqlite3_value*);
|
|
|
3427 SQLITE_API int sqlite3_value_int(sqlite3_value*);
|
|
|
3428 SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
|
|
|
3429 SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
|
|
|
3430 SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
|
|
|
3431 SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
|
|
|
3432 SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
|
|
|
3433 SQLITE_API int sqlite3_value_type(sqlite3_value*);
|
|
|
3434 SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
|
|
|
3435
|
|
|
3436 /*
|
|
|
3437 ** CAPI3REF: Obtain Aggregate Function Context
|
|
|
3438 **
|
|
|
3439 ** Implementions of aggregate SQL functions use this
|
|
|
3440 ** routine to allocate memory for storing their state.
|
|
|
3441 **
|
|
|
3442 ** ^The first time the sqlite3_aggregate_context(C,N) routine is called
|
|
|
3443 ** for a particular aggregate function, SQLite
|
|
|
3444 ** allocates N of memory, zeroes out that memory, and returns a pointer
|
|
|
3445 ** to the new memory. ^On second and subsequent calls to
|
|
|
3446 ** sqlite3_aggregate_context() for the same aggregate function instance,
|
|
|
3447 ** the same buffer is returned. Sqlite3_aggregate_context() is normally
|
|
|
3448 ** called once for each invocation of the xStep callback and then one
|
|
|
3449 ** last time when the xFinal callback is invoked. ^(When no rows match
|
|
|
3450 ** an aggregate query, the xStep() callback of the aggregate function
|
|
|
3451 ** implementation is never called and xFinal() is called exactly once.
|
|
|
3452 ** In those cases, sqlite3_aggregate_context() might be called for the
|
|
|
3453 ** first time from within xFinal().)^
|
|
|
3454 **
|
|
|
3455 ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer if N is
|
|
|
3456 ** less than or equal to zero or if a memory allocate error occurs.
|
|
|
3457 **
|
|
|
3458 ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
|
|
|
3459 ** determined by the N parameter on first successful call. Changing the
|
|
|
3460 ** value of N in subsequent call to sqlite3_aggregate_context() within
|
|
|
3461 ** the same aggregate function instance will not resize the memory
|
|
|
3462 ** allocation.)^
|
|
|
3463 **
|
|
|
3464 ** ^SQLite automatically frees the memory allocated by
|
|
|
3465 ** sqlite3_aggregate_context() when the aggregate query concludes.
|
|
|
3466 **
|
|
|
3467 ** The first parameter must be a copy of the
|
|
|
3468 ** [sqlite3_context | SQL function context] that is the first parameter
|
|
|
3469 ** to the xStep or xFinal callback routine that implements the aggregate
|
|
|
3470 ** function.
|
|
|
3471 **
|
|
|
3472 ** This routine must be called from the same thread in which
|
|
|
3473 ** the aggregate SQL function is running.
|
|
|
3474 */
|
|
|
3475 SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
|
|
|
3476
|
|
|
3477 /*
|
|
|
3478 ** CAPI3REF: User Data For Functions
|
|
|
3479 **
|
|
|
3480 ** ^The sqlite3_user_data() interface returns a copy of
|
|
|
3481 ** the pointer that was the pUserData parameter (the 5th parameter)
|
|
|
3482 ** of the [sqlite3_create_function()]
|
|
|
3483 ** and [sqlite3_create_function16()] routines that originally
|
|
|
3484 ** registered the application defined function.
|
|
|
3485 **
|
|
|
3486 ** This routine must be called from the same thread in which
|
|
|
3487 ** the application-defined function is running.
|
|
|
3488 */
|
|
|
3489 SQLITE_API void *sqlite3_user_data(sqlite3_context*);
|
|
|
3490
|
|
|
3491 /*
|
|
|
3492 ** CAPI3REF: Database Connection For Functions
|
|
|
3493 **
|
|
|
3494 ** ^The sqlite3_context_db_handle() interface returns a copy of
|
|
|
3495 ** the pointer to the [database connection] (the 1st parameter)
|
|
|
3496 ** of the [sqlite3_create_function()]
|
|
|
3497 ** and [sqlite3_create_function16()] routines that originally
|
|
|
3498 ** registered the application defined function.
|
|
|
3499 */
|
|
|
3500 SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
|
|
|
3501
|
|
|
3502 /*
|
|
|
3503 ** CAPI3REF: Function Auxiliary Data
|
|
|
3504 **
|
|
|
3505 ** The following two functions may be used by scalar SQL functions to
|
|
|
3506 ** associate metadata with argument values. If the same value is passed to
|
|
|
3507 ** multiple invocations of the same SQL function during query execution, under
|
|
|
3508 ** some circumstances the associated metadata may be preserved. This may
|
|
|
3509 ** be used, for example, to add a regular-expression matching scalar
|
|
|
3510 ** function. The compiled version of the regular expression is stored as
|
|
|
3511 ** metadata associated with the SQL value passed as the regular expression
|
|
|
3512 ** pattern. The compiled regular expression can be reused on multiple
|
|
|
3513 ** invocations of the same function so that the original pattern string
|
|
|
3514 ** does not need to be recompiled on each invocation.
|
|
|
3515 **
|
|
|
3516 ** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
|
|
|
3517 ** associated by the sqlite3_set_auxdata() function with the Nth argument
|
|
|
3518 ** value to the application-defined function. ^If no metadata has been ever
|
|
|
3519 ** been set for the Nth argument of the function, or if the corresponding
|
|
|
3520 ** function parameter has changed since the meta-data was set,
|
|
|
3521 ** then sqlite3_get_auxdata() returns a NULL pointer.
|
|
|
3522 **
|
|
|
3523 ** ^The sqlite3_set_auxdata() interface saves the metadata
|
|
|
3524 ** pointed to by its 3rd parameter as the metadata for the N-th
|
|
|
3525 ** argument of the application-defined function. Subsequent
|
|
|
3526 ** calls to sqlite3_get_auxdata() might return this data, if it has
|
|
|
3527 ** not been destroyed.
|
|
|
3528 ** ^If it is not NULL, SQLite will invoke the destructor
|
|
|
3529 ** function given by the 4th parameter to sqlite3_set_auxdata() on
|
|
|
3530 ** the metadata when the corresponding function parameter changes
|
|
|
3531 ** or when the SQL statement completes, whichever comes first.
|
|
|
3532 **
|
|
|
3533 ** SQLite is free to call the destructor and drop metadata on any
|
|
|
3534 ** parameter of any function at any time. ^The only guarantee is that
|
|
|
3535 ** the destructor will be called before the metadata is dropped.
|
|
|
3536 **
|
|
|
3537 ** ^(In practice, metadata is preserved between function calls for
|
|
|
3538 ** expressions that are constant at compile time. This includes literal
|
|
|
3539 ** values and [parameters].)^
|
|
|
3540 **
|
|
|
3541 ** These routines must be called from the same thread in which
|
|
|
3542 ** the SQL function is running.
|
|
|
3543 */
|
|
|
3544 SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
|
|
|
3545 SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
|
|
|
3546
|
|
|
3547
|
|
|
3548 /*
|
|
|
3549 ** CAPI3REF: Constants Defining Special Destructor Behavior
|
|
|
3550 **
|
|
|
3551 ** These are special values for the destructor that is passed in as the
|
|
|
3552 ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
|
|
|
3553 ** argument is SQLITE_STATIC, it means that the content pointer is constant
|
|
|
3554 ** and will never change. It does not need to be destroyed. ^The
|
|
|
3555 ** SQLITE_TRANSIENT value means that the content will likely change in
|
|
|
3556 ** the near future and that SQLite should make its own private copy of
|
|
|
3557 ** the content before returning.
|
|
|
3558 **
|
|
|
3559 ** The typedef is necessary to work around problems in certain
|
|
|
3560 ** C++ compilers. See ticket #2191.
|
|
|
3561 */
|
|
|
3562 typedef void (*sqlite3_destructor_type)(void*);
|
|
|
3563 #define SQLITE_STATIC ((sqlite3_destructor_type)0)
|
|
|
3564 #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
|
|
|
3565
|
|
|
3566 /*
|
|
|
3567 ** CAPI3REF: Setting The Result Of An SQL Function
|
|
|
3568 **
|
|
|
3569 ** These routines are used by the xFunc or xFinal callbacks that
|
|
|
3570 ** implement SQL functions and aggregates. See
|
|
|
3571 ** [sqlite3_create_function()] and [sqlite3_create_function16()]
|
|
|
3572 ** for additional information.
|
|
|
3573 **
|
|
|
3574 ** These functions work very much like the [parameter binding] family of
|
|
|
3575 ** functions used to bind values to host parameters in prepared statements.
|
|
|
3576 ** Refer to the [SQL parameter] documentation for additional information.
|
|
|
3577 **
|
|
|
3578 ** ^The sqlite3_result_blob() interface sets the result from
|
|
|
3579 ** an application-defined function to be the BLOB whose content is pointed
|
|
|
3580 ** to by the second parameter and which is N bytes long where N is the
|
|
|
3581 ** third parameter.
|
|
|
3582 **
|
|
|
3583 ** ^The sqlite3_result_zeroblob() interfaces set the result of
|
|
|
3584 ** the application-defined function to be a BLOB containing all zero
|
|
|
3585 ** bytes and N bytes in size, where N is the value of the 2nd parameter.
|
|
|
3586 **
|
|
|
3587 ** ^The sqlite3_result_double() interface sets the result from
|
|
|
3588 ** an application-defined function to be a floating point value specified
|
|
|
3589 ** by its 2nd argument.
|
|
|
3590 **
|
|
|
3591 ** ^The sqlite3_result_error() and sqlite3_result_error16() functions
|
|
|
3592 ** cause the implemented SQL function to throw an exception.
|
|
|
3593 ** ^SQLite uses the string pointed to by the
|
|
|
3594 ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
|
|
|
3595 ** as the text of an error message. ^SQLite interprets the error
|
|
|
3596 ** message string from sqlite3_result_error() as UTF-8. ^SQLite
|
|
|
3597 ** interprets the string from sqlite3_result_error16() as UTF-16 in native
|
|
|
3598 ** byte order. ^If the third parameter to sqlite3_result_error()
|
|
|
3599 ** or sqlite3_result_error16() is negative then SQLite takes as the error
|
|
|
3600 ** message all text up through the first zero character.
|
|
|
3601 ** ^If the third parameter to sqlite3_result_error() or
|
|
|
3602 ** sqlite3_result_error16() is non-negative then SQLite takes that many
|
|
|
3603 ** bytes (not characters) from the 2nd parameter as the error message.
|
|
|
3604 ** ^The sqlite3_result_error() and sqlite3_result_error16()
|
|
|
3605 ** routines make a private copy of the error message text before
|
|
|
3606 ** they return. Hence, the calling function can deallocate or
|
|
|
3607 ** modify the text after they return without harm.
|
|
|
3608 ** ^The sqlite3_result_error_code() function changes the error code
|
|
|
3609 ** returned by SQLite as a result of an error in a function. ^By default,
|
|
|
3610 ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
|
|
|
3611 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
|
|
|
3612 **
|
|
|
3613 ** ^The sqlite3_result_toobig() interface causes SQLite to throw an error
|
|
|
3614 ** indicating that a string or BLOB is too long to represent.
|
|
|
3615 **
|
|
|
3616 ** ^The sqlite3_result_nomem() interface causes SQLite to throw an error
|
|
|
3617 ** indicating that a memory allocation failed.
|
|
|
3618 **
|
|
|
3619 ** ^The sqlite3_result_int() interface sets the return value
|
|
|
3620 ** of the application-defined function to be the 32-bit signed integer
|
|
|
3621 ** value given in the 2nd argument.
|
|
|
3622 ** ^The sqlite3_result_int64() interface sets the return value
|
|
|
3623 ** of the application-defined function to be the 64-bit signed integer
|
|
|
3624 ** value given in the 2nd argument.
|
|
|
3625 **
|
|
|
3626 ** ^The sqlite3_result_null() interface sets the return value
|
|
|
3627 ** of the application-defined function to be NULL.
|
|
|
3628 **
|
|
|
3629 ** ^The sqlite3_result_text(), sqlite3_result_text16(),
|
|
|
3630 ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
|
|
|
3631 ** set the return value of the application-defined function to be
|
|
|
3632 ** a text string which is represented as UTF-8, UTF-16 native byte order,
|
|
|
3633 ** UTF-16 little endian, or UTF-16 big endian, respectively.
|
|
|
3634 ** ^SQLite takes the text result from the application from
|
|
|
3635 ** the 2nd parameter of the sqlite3_result_text* interfaces.
|
|
|
3636 ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
|
|
|
3637 ** is negative, then SQLite takes result text from the 2nd parameter
|
|
|
3638 ** through the first zero character.
|
|
|
3639 ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
|
|
|
3640 ** is non-negative, then as many bytes (not characters) of the text
|
|
|
3641 ** pointed to by the 2nd parameter are taken as the application-defined
|
|
|
3642 ** function result.
|
|
|
3643 ** ^If the 4th parameter to the sqlite3_result_text* interfaces
|
|
|
3644 ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
|
|
|
3645 ** function as the destructor on the text or BLOB result when it has
|
|
|
3646 ** finished using that result.
|
|
|
3647 ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
|
|
|
3648 ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
|
|
|
3649 ** assumes that the text or BLOB result is in constant space and does not
|
|
|
3650 ** copy the content of the parameter nor call a destructor on the content
|
|
|
3651 ** when it has finished using that result.
|
|
|
3652 ** ^If the 4th parameter to the sqlite3_result_text* interfaces
|
|
|
3653 ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
|
|
|
3654 ** then SQLite makes a copy of the result into space obtained from
|
|
|
3655 ** from [sqlite3_malloc()] before it returns.
|
|
|
3656 **
|
|
|
3657 ** ^The sqlite3_result_value() interface sets the result of
|
|
|
3658 ** the application-defined function to be a copy the
|
|
|
3659 ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
|
|
|
3660 ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
|
|
|
3661 ** so that the [sqlite3_value] specified in the parameter may change or
|
|
|
3662 ** be deallocated after sqlite3_result_value() returns without harm.
|
|
|
3663 ** ^A [protected sqlite3_value] object may always be used where an
|
|
|
3664 ** [unprotected sqlite3_value] object is required, so either
|
|
|
3665 ** kind of [sqlite3_value] object can be used with this interface.
|
|
|
3666 **
|
|
|
3667 ** If these routines are called from within the different thread
|
|
|
3668 ** than the one containing the application-defined function that received
|
|
|
3669 ** the [sqlite3_context] pointer, the results are undefined.
|
|
|
3670 */
|
|
|
3671 SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
|
|
|
3672 SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
|
|
|
3673 SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
|
|
|
3674 SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
|
|
|
3675 SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
|
|
|
3676 SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
|
|
|
3677 SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
|
|
|
3678 SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
|
|
|
3679 SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
|
|
|
3680 SQLITE_API void sqlite3_result_null(sqlite3_context*);
|
|
|
3681 SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
|
|
|
3682 SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
|
|
|
3683 SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
|
|
|
3684 SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
|
|
|
3685 SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
|
|
|
3686 SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
|
|
|
3687
|
|
|
3688 /*
|
|
|
3689 ** CAPI3REF: Define New Collating Sequences
|
|
|
3690 **
|
|
|
3691 ** These functions are used to add new collation sequences to the
|
|
|
3692 ** [database connection] specified as the first argument.
|
|
|
3693 **
|
|
|
3694 ** ^The name of the new collation sequence is specified as a UTF-8 string
|
|
|
3695 ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
|
|
|
3696 ** and a UTF-16 string for sqlite3_create_collation16(). ^In all cases
|
|
|
3697 ** the name is passed as the second function argument.
|
|
|
3698 **
|
|
|
3699 ** ^The third argument may be one of the constants [SQLITE_UTF8],
|
|
|
3700 ** [SQLITE_UTF16LE], or [SQLITE_UTF16BE], indicating that the user-supplied
|
|
|
3701 ** routine expects to be passed pointers to strings encoded using UTF-8,
|
|
|
3702 ** UTF-16 little-endian, or UTF-16 big-endian, respectively. ^The
|
|
|
3703 ** third argument might also be [SQLITE_UTF16] to indicate that the routine
|
|
|
3704 ** expects pointers to be UTF-16 strings in the native byte order, or the
|
|
|
3705 ** argument can be [SQLITE_UTF16_ALIGNED] if the
|
|
|
3706 ** the routine expects pointers to 16-bit word aligned strings
|
|
|
3707 ** of UTF-16 in the native byte order.
|
|
|
3708 **
|
|
|
3709 ** A pointer to the user supplied routine must be passed as the fifth
|
|
|
3710 ** argument. ^If it is NULL, this is the same as deleting the collation
|
|
|
3711 ** sequence (so that SQLite cannot call it anymore).
|
|
|
3712 ** ^Each time the application supplied function is invoked, it is passed
|
|
|
3713 ** as its first parameter a copy of the void* passed as the fourth argument
|
|
|
3714 ** to sqlite3_create_collation() or sqlite3_create_collation16().
|
|
|
3715 **
|
|
|
3716 ** ^The remaining arguments to the application-supplied routine are two strings,
|
|
|
3717 ** each represented by a (length, data) pair and encoded in the encoding
|
|
|
3718 ** that was passed as the third argument when the collation sequence was
|
|
|
3719 ** registered. The application defined collation routine should
|
|
|
3720 ** return negative, zero or positive if the first string is less than,
|
|
|
3721 ** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
|
|
|
3722 **
|
|
|
3723 ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
|
|
|
3724 ** except that it takes an extra argument which is a destructor for
|
|
|
3725 ** the collation. ^The destructor is called when the collation is
|
|
|
3726 ** destroyed and is passed a copy of the fourth parameter void* pointer
|
|
|
3727 ** of the sqlite3_create_collation_v2().
|
|
|
3728 ** ^Collations are destroyed when they are overridden by later calls to the
|
|
|
3729 ** collation creation functions or when the [database connection] is closed
|
|
|
3730 ** using [sqlite3_close()].
|
|
|
3731 **
|
|
|
3732 ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
|
|
|
3733 */
|
|
|
3734 SQLITE_API int sqlite3_create_collation(
|
|
|
3735 sqlite3*,
|
|
|
3736 const char *zName,
|
|
|
3737 int eTextRep,
|
|
|
3738 void*,
|
|
|
3739 int(*xCompare)(void*,int,const void*,int,const void*)
|
|
|
3740 );
|
|
|
3741 SQLITE_API int sqlite3_create_collation_v2(
|
|
|
3742 sqlite3*,
|
|
|
3743 const char *zName,
|
|
|
3744 int eTextRep,
|
|
|
3745 void*,
|
|
|
3746 int(*xCompare)(void*,int,const void*,int,const void*),
|
|
|
3747 void(*xDestroy)(void*)
|
|
|
3748 );
|
|
|
3749 SQLITE_API int sqlite3_create_collation16(
|
|
|
3750 sqlite3*,
|
|
|
3751 const void *zName,
|
|
|
3752 int eTextRep,
|
|
|
3753 void*,
|
|
|
3754 int(*xCompare)(void*,int,const void*,int,const void*)
|
|
|
3755 );
|
|
|
3756
|
|
|
3757 /*
|
|
|
3758 ** CAPI3REF: Collation Needed Callbacks
|
|
|
3759 **
|
|
|
3760 ** ^To avoid having to register all collation sequences before a database
|
|
|
3761 ** can be used, a single callback function may be registered with the
|
|
|
3762 ** [database connection] to be invoked whenever an undefined collation
|
|
|
3763 ** sequence is required.
|
|
|
3764 **
|
|
|
3765 ** ^If the function is registered using the sqlite3_collation_needed() API,
|
|
|
3766 ** then it is passed the names of undefined collation sequences as strings
|
|
|
3767 ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
|
|
|
3768 ** the names are passed as UTF-16 in machine native byte order.
|
|
|
3769 ** ^A call to either function replaces the existing collation-needed callback.
|
|
|
3770 **
|
|
|
3771 ** ^(When the callback is invoked, the first argument passed is a copy
|
|
|
3772 ** of the second argument to sqlite3_collation_needed() or
|
|
|
3773 ** sqlite3_collation_needed16(). The second argument is the database
|
|
|
3774 ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
|
|
|
3775 ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
|
|
|
3776 ** sequence function required. The fourth parameter is the name of the
|
|
|
3777 ** required collation sequence.)^
|
|
|
3778 **
|
|
|
3779 ** The callback function should register the desired collation using
|
|
|
3780 ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
|
|
|
3781 ** [sqlite3_create_collation_v2()].
|
|
|
3782 */
|
|
|
3783 SQLITE_API int sqlite3_collation_needed(
|
|
|
3784 sqlite3*,
|
|
|
3785 void*,
|
|
|
3786 void(*)(void*,sqlite3*,int eTextRep,const char*)
|
|
|
3787 );
|
|
|
3788 SQLITE_API int sqlite3_collation_needed16(
|
|
|
3789 sqlite3*,
|
|
|
3790 void*,
|
|
|
3791 void(*)(void*,sqlite3*,int eTextRep,const void*)
|
|
|
3792 );
|
|
|
3793
|
|
|
3794 #ifdef SQLITE_HAS_CODEC
|
|
|
3795 /*
|
|
|
3796 ** Specify the key for an encrypted database. This routine should be
|
|
|
3797 ** called right after sqlite3_open().
|
|
|
3798 **
|
|
|
3799 ** The code to implement this API is not available in the public release
|
|
|
3800 ** of SQLite.
|
|
|
3801 */
|
|
|
3802 SQLITE_API int sqlite3_key(
|
|
|
3803 sqlite3 *db, /* Database to be rekeyed */
|
|
|
3804 const void *pKey, int nKey /* The key */
|
|
|
3805 );
|
|
|
3806
|
|
|
3807 /*
|
|
|
3808 ** Change the key on an open database. If the current database is not
|
|
|
3809 ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
|
|
|
3810 ** database is decrypted.
|
|
|
3811 **
|
|
|
3812 ** The code to implement this API is not available in the public release
|
|
|
3813 ** of SQLite.
|
|
|
3814 */
|
|
|
3815 SQLITE_API int sqlite3_rekey(
|
|
|
3816 sqlite3 *db, /* Database to be rekeyed */
|
|
|
3817 const void *pKey, int nKey /* The new key */
|
|
|
3818 );
|
|
|
3819
|
|
|
3820 /*
|
|
|
3821 ** Specify the activation key for a SEE database. Unless
|
|
|
3822 ** activated, none of the SEE routines will work.
|
|
|
3823 */
|
|
|
3824 SQLITE_API void sqlite3_activate_see(
|
|
|
3825 const char *zPassPhrase /* Activation phrase */
|
|
|
3826 );
|
|
|
3827 #endif
|
|
|
3828
|
|
|
3829 #ifdef SQLITE_ENABLE_CEROD
|
|
|
3830 /*
|
|
|
3831 ** Specify the activation key for a CEROD database. Unless
|
|
|
3832 ** activated, none of the CEROD routines will work.
|
|
|
3833 */
|
|
|
3834 SQLITE_API void sqlite3_activate_cerod(
|
|
|
3835 const char *zPassPhrase /* Activation phrase */
|
|
|
3836 );
|
|
|
3837 #endif
|
|
|
3838
|
|
|
3839 /*
|
|
|
3840 ** CAPI3REF: Suspend Execution For A Short Time
|
|
|
3841 **
|
|
|
3842 ** ^The sqlite3_sleep() function causes the current thread to suspend execution
|
|
|
3843 ** for at least a number of milliseconds specified in its parameter.
|
|
|
3844 **
|
|
|
3845 ** ^If the operating system does not support sleep requests with
|
|
|
3846 ** millisecond time resolution, then the time will be rounded up to
|
|
|
3847 ** the nearest second. ^The number of milliseconds of sleep actually
|
|
|
3848 ** requested from the operating system is returned.
|
|
|
3849 **
|
|
|
3850 ** ^SQLite implements this interface by calling the xSleep()
|
|
|
3851 ** method of the default [sqlite3_vfs] object.
|
|
|
3852 */
|
|
|
3853 SQLITE_API int sqlite3_sleep(int);
|
|
|
3854
|
|
|
3855 /*
|
|
|
3856 ** CAPI3REF: Name Of The Folder Holding Temporary Files
|
|
|
3857 **
|
|
|
3858 ** ^(If this global variable is made to point to a string which is
|
|
|
3859 ** the name of a folder (a.k.a. directory), then all temporary files
|
|
|
3860 ** created by SQLite when using a built-in [sqlite3_vfs | VFS]
|
|
|
3861 ** will be placed in that directory.)^ ^If this variable
|
|
|
3862 ** is a NULL pointer, then SQLite performs a search for an appropriate
|
|
|
3863 ** temporary file directory.
|
|
|
3864 **
|
|
|
3865 ** It is not safe to read or modify this variable in more than one
|
|
|
3866 ** thread at a time. It is not safe to read or modify this variable
|
|
|
3867 ** if a [database connection] is being used at the same time in a separate
|
|
|
3868 ** thread.
|
|
|
3869 ** It is intended that this variable be set once
|
|
|
3870 ** as part of process initialization and before any SQLite interface
|
|
|
3871 ** routines have been called and that this variable remain unchanged
|
|
|
3872 ** thereafter.
|
|
|
3873 **
|
|
|
3874 ** ^The [temp_store_directory pragma] may modify this variable and cause
|
|
|
3875 ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
|
|
|
3876 ** the [temp_store_directory pragma] always assumes that any string
|
|
|
3877 ** that this variable points to is held in memory obtained from
|
|
|
3878 ** [sqlite3_malloc] and the pragma may attempt to free that memory
|
|
|
3879 ** using [sqlite3_free].
|
|
|
3880 ** Hence, if this variable is modified directly, either it should be
|
|
|
3881 ** made NULL or made to point to memory obtained from [sqlite3_malloc]
|
|
|
3882 ** or else the use of the [temp_store_directory pragma] should be avoided.
|
|
|
3883 */
|
|
|
3884 SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
|
|
|
3885
|
|
|
3886 /*
|
|
|
3887 ** CAPI3REF: Test For Auto-Commit Mode
|
|
|
3888 ** KEYWORDS: {autocommit mode}
|
|
|
3889 **
|
|
|
3890 ** ^The sqlite3_get_autocommit() interface returns non-zero or
|
|
|
3891 ** zero if the given database connection is or is not in autocommit mode,
|
|
|
3892 ** respectively. ^Autocommit mode is on by default.
|
|
|
3893 ** ^Autocommit mode is disabled by a [BEGIN] statement.
|
|
|
3894 ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
|
|
|
3895 **
|
|
|
3896 ** If certain kinds of errors occur on a statement within a multi-statement
|
|
|
3897 ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
|
|
|
3898 ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
|
|
|
3899 ** transaction might be rolled back automatically. The only way to
|
|
|
3900 ** find out whether SQLite automatically rolled back the transaction after
|
|
|
3901 ** an error is to use this function.
|
|
|
3902 **
|
|
|
3903 ** If another thread changes the autocommit status of the database
|
|
|
3904 ** connection while this routine is running, then the return value
|
|
|
3905 ** is undefined.
|
|
|
3906 */
|
|
|
3907 SQLITE_API int sqlite3_get_autocommit(sqlite3*);
|
|
|
3908
|
|
|
3909 /*
|
|
|
3910 ** CAPI3REF: Find The Database Handle Of A Prepared Statement
|
|
|
3911 **
|
|
|
3912 ** ^The sqlite3_db_handle interface returns the [database connection] handle
|
|
|
3913 ** to which a [prepared statement] belongs. ^The [database connection]
|
|
|
3914 ** returned by sqlite3_db_handle is the same [database connection]
|
|
|
3915 ** that was the first argument
|
|
|
3916 ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
|
|
|
3917 ** create the statement in the first place.
|
|
|
3918 */
|
|
|
3919 SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
|
|
|
3920
|
|
|
3921 /*
|
|
|
3922 ** CAPI3REF: Find the next prepared statement
|
|
|
3923 **
|
|
|
3924 ** ^This interface returns a pointer to the next [prepared statement] after
|
|
|
3925 ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
|
|
|
3926 ** then this interface returns a pointer to the first prepared statement
|
|
|
3927 ** associated with the database connection pDb. ^If no prepared statement
|
|
|
3928 ** satisfies the conditions of this routine, it returns NULL.
|
|
|
3929 **
|
|
|
3930 ** The [database connection] pointer D in a call to
|
|
|
3931 ** [sqlite3_next_stmt(D,S)] must refer to an open database
|
|
|
3932 ** connection and in particular must not be a NULL pointer.
|
|
|
3933 */
|
|
|
3934 SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
|
|
|
3935
|
|
|
3936 /*
|
|
|
3937 ** CAPI3REF: Commit And Rollback Notification Callbacks
|
|
|
3938 **
|
|
|
3939 ** ^The sqlite3_commit_hook() interface registers a callback
|
|
|
3940 ** function to be invoked whenever a transaction is [COMMIT | committed].
|
|
|
3941 ** ^Any callback set by a previous call to sqlite3_commit_hook()
|
|
|
3942 ** for the same database connection is overridden.
|
|
|
3943 ** ^The sqlite3_rollback_hook() interface registers a callback
|
|
|
3944 ** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
|
|
|
3945 ** ^Any callback set by a previous call to sqlite3_rollback_hook()
|
|
|
3946 ** for the same database connection is overridden.
|
|
|
3947 ** ^The pArg argument is passed through to the callback.
|
|
|
3948 ** ^If the callback on a commit hook function returns non-zero,
|
|
|
3949 ** then the commit is converted into a rollback.
|
|
|
3950 **
|
|
|
3951 ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
|
|
|
3952 ** return the P argument from the previous call of the same function
|
|
|
3953 ** on the same [database connection] D, or NULL for
|
|
|
3954 ** the first call for each function on D.
|
|
|
3955 **
|
|
|
3956 ** The callback implementation must not do anything that will modify
|
|
|
3957 ** the database connection that invoked the callback. Any actions
|
|
|
3958 ** to modify the database connection must be deferred until after the
|
|
|
3959 ** completion of the [sqlite3_step()] call that triggered the commit
|
|
|
3960 ** or rollback hook in the first place.
|
|
|
3961 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
|
|
|
3962 ** database connections for the meaning of "modify" in this paragraph.
|
|
|
3963 **
|
|
|
3964 ** ^Registering a NULL function disables the callback.
|
|
|
3965 **
|
|
|
3966 ** ^When the commit hook callback routine returns zero, the [COMMIT]
|
|
|
3967 ** operation is allowed to continue normally. ^If the commit hook
|
|
|
3968 ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
|
|
|
3969 ** ^The rollback hook is invoked on a rollback that results from a commit
|
|
|
3970 ** hook returning non-zero, just as it would be with any other rollback.
|
|
|
3971 **
|
|
|
3972 ** ^For the purposes of this API, a transaction is said to have been
|
|
|
3973 ** rolled back if an explicit "ROLLBACK" statement is executed, or
|
|
|
3974 ** an error or constraint causes an implicit rollback to occur.
|
|
|
3975 ** ^The rollback callback is not invoked if a transaction is
|
|
|
3976 ** automatically rolled back because the database connection is closed.
|
|
|
3977 **
|
|
|
3978 ** See also the [sqlite3_update_hook()] interface.
|
|
|
3979 */
|
|
|
3980 SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
|
|
|
3981 SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
|
|
|
3982
|
|
|
3983 /*
|
|
|
3984 ** CAPI3REF: Data Change Notification Callbacks
|
|
|
3985 **
|
|
|
3986 ** ^The sqlite3_update_hook() interface registers a callback function
|
|
|
3987 ** with the [database connection] identified by the first argument
|
|
|
3988 ** to be invoked whenever a row is updated, inserted or deleted.
|
|
|
3989 ** ^Any callback set by a previous call to this function
|
|
|
3990 ** for the same database connection is overridden.
|
|
|
3991 **
|
|
|
3992 ** ^The second argument is a pointer to the function to invoke when a
|
|
|
3993 ** row is updated, inserted or deleted.
|
|
|
3994 ** ^The first argument to the callback is a copy of the third argument
|
|
|
3995 ** to sqlite3_update_hook().
|
|
|
3996 ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
|
|
|
3997 ** or [SQLITE_UPDATE], depending on the operation that caused the callback
|
|
|
3998 ** to be invoked.
|
|
|
3999 ** ^The third and fourth arguments to the callback contain pointers to the
|
|
|
4000 ** database and table name containing the affected row.
|
|
|
4001 ** ^The final callback parameter is the [rowid] of the row.
|
|
|
4002 ** ^In the case of an update, this is the [rowid] after the update takes place.
|
|
|
4003 **
|
|
|
4004 ** ^(The update hook is not invoked when internal system tables are
|
|
|
4005 ** modified (i.e. sqlite_master and sqlite_sequence).)^
|
|
|
4006 **
|
|
|
4007 ** ^In the current implementation, the update hook
|
|
|
4008 ** is not invoked when duplication rows are deleted because of an
|
|
|
4009 ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
|
|
|
4010 ** invoked when rows are deleted using the [truncate optimization].
|
|
|
4011 ** The exceptions defined in this paragraph might change in a future
|
|
|
4012 ** release of SQLite.
|
|
|
4013 **
|
|
|
4014 ** The update hook implementation must not do anything that will modify
|
|
|
4015 ** the database connection that invoked the update hook. Any actions
|
|
|
4016 ** to modify the database connection must be deferred until after the
|
|
|
4017 ** completion of the [sqlite3_step()] call that triggered the update hook.
|
|
|
4018 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
|
|
|
4019 ** database connections for the meaning of "modify" in this paragraph.
|
|
|
4020 **
|
|
|
4021 ** ^The sqlite3_update_hook(D,C,P) function
|
|
|
4022 ** returns the P argument from the previous call
|
|
|
4023 ** on the same [database connection] D, or NULL for
|
|
|
4024 ** the first call on D.
|
|
|
4025 **
|
|
|
4026 ** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
|
|
|
4027 ** interfaces.
|
|
|
4028 */
|
|
|
4029 SQLITE_API void *sqlite3_update_hook(
|
|
|
4030 sqlite3*,
|
|
|
4031 void(*)(void *,int ,char const *,char const *,sqlite3_int64),
|
|
|
4032 void*
|
|
|
4033 );
|
|
|
4034
|
|
|
4035 /*
|
|
|
4036 ** CAPI3REF: Enable Or Disable Shared Pager Cache
|
|
|
4037 ** KEYWORDS: {shared cache}
|
|
|
4038 **
|
|
|
4039 ** ^(This routine enables or disables the sharing of the database cache
|
|
|
4040 ** and schema data structures between [database connection | connections]
|
|
|
4041 ** to the same database. Sharing is enabled if the argument is true
|
|
|
4042 ** and disabled if the argument is false.)^
|
|
|
4043 **
|
|
|
4044 ** ^Cache sharing is enabled and disabled for an entire process.
|
|
|
4045 ** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
|
|
|
4046 ** sharing was enabled or disabled for each thread separately.
|
|
|
4047 **
|
|
|
4048 ** ^(The cache sharing mode set by this interface effects all subsequent
|
|
|
4049 ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
|
|
|
4050 ** Existing database connections continue use the sharing mode
|
|
|
4051 ** that was in effect at the time they were opened.)^
|
|
|
4052 **
|
|
|
4053 ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
|
|
|
4054 ** successfully. An [error code] is returned otherwise.)^
|
|
|
4055 **
|
|
|
4056 ** ^Shared cache is disabled by default. But this might change in
|
|
|
4057 ** future releases of SQLite. Applications that care about shared
|
|
|
4058 ** cache setting should set it explicitly.
|
|
|
4059 **
|
|
|
4060 ** See Also: [SQLite Shared-Cache Mode]
|
|
|
4061 */
|
|
|
4062 SQLITE_API int sqlite3_enable_shared_cache(int);
|
|
|
4063
|
|
|
4064 /*
|
|
|
4065 ** CAPI3REF: Attempt To Free Heap Memory
|
|
|
4066 **
|
|
|
4067 ** ^The sqlite3_release_memory() interface attempts to free N bytes
|
|
|
4068 ** of heap memory by deallocating non-essential memory allocations
|
|
|
4069 ** held by the database library. Memory used to cache database
|
|
|
4070 ** pages to improve performance is an example of non-essential memory.
|
|
|
4071 ** ^sqlite3_release_memory() returns the number of bytes actually freed,
|
|
|
4072 ** which might be more or less than the amount requested.
|
|
|
4073 */
|
|
|
4074 SQLITE_API int sqlite3_release_memory(int);
|
|
|
4075
|
|
|
4076 /*
|
|
|
4077 ** CAPI3REF: Impose A Limit On Heap Size
|
|
|
4078 **
|
|
|
4079 ** ^The sqlite3_soft_heap_limit() interface places a "soft" limit
|
|
|
4080 ** on the amount of heap memory that may be allocated by SQLite.
|
|
|
4081 ** ^If an internal allocation is requested that would exceed the
|
|
|
4082 ** soft heap limit, [sqlite3_release_memory()] is invoked one or
|
|
|
4083 ** more times to free up some space before the allocation is performed.
|
|
|
4084 **
|
|
|
4085 ** ^The limit is called "soft" because if [sqlite3_release_memory()]
|
|
|
4086 ** cannot free sufficient memory to prevent the limit from being exceeded,
|
|
|
4087 ** the memory is allocated anyway and the current operation proceeds.
|
|
|
4088 **
|
|
|
4089 ** ^A negative or zero value for N means that there is no soft heap limit and
|
|
|
4090 ** [sqlite3_release_memory()] will only be called when memory is exhausted.
|
|
|
4091 ** ^The default value for the soft heap limit is zero.
|
|
|
4092 **
|
|
|
4093 ** ^(SQLite makes a best effort to honor the soft heap limit.
|
|
|
4094 ** But if the soft heap limit cannot be honored, execution will
|
|
|
4095 ** continue without error or notification.)^ This is why the limit is
|
|
|
4096 ** called a "soft" limit. It is advisory only.
|
|
|
4097 **
|
|
|
4098 ** Prior to SQLite version 3.5.0, this routine only constrained the memory
|
|
|
4099 ** allocated by a single thread - the same thread in which this routine
|
|
|
4100 ** runs. Beginning with SQLite version 3.5.0, the soft heap limit is
|
|
|
4101 ** applied to all threads. The value specified for the soft heap limit
|
|
|
4102 ** is an upper bound on the total memory allocation for all threads. In
|
|
|
4103 ** version 3.5.0 there is no mechanism for limiting the heap usage for
|
|
|
4104 ** individual threads.
|
|
|
4105 */
|
|
|
4106 SQLITE_API void sqlite3_soft_heap_limit(int);
|
|
|
4107
|
|
|
4108 /*
|
|
|
4109 ** CAPI3REF: Extract Metadata About A Column Of A Table
|
|
|
4110 **
|
|
|
4111 ** ^This routine returns metadata about a specific column of a specific
|
|
|
4112 ** database table accessible using the [database connection] handle
|
|
|
4113 ** passed as the first function argument.
|
|
|
4114 **
|
|
|
4115 ** ^The column is identified by the second, third and fourth parameters to
|
|
|
4116 ** this function. ^The second parameter is either the name of the database
|
|
|
4117 ** (i.e. "main", "temp", or an attached database) containing the specified
|
|
|
4118 ** table or NULL. ^If it is NULL, then all attached databases are searched
|
|
|
4119 ** for the table using the same algorithm used by the database engine to
|
|
|
4120 ** resolve unqualified table references.
|
|
|
4121 **
|
|
|
4122 ** ^The third and fourth parameters to this function are the table and column
|
|
|
4123 ** name of the desired column, respectively. Neither of these parameters
|
|
|
4124 ** may be NULL.
|
|
|
4125 **
|
|
|
4126 ** ^Metadata is returned by writing to the memory locations passed as the 5th
|
|
|
4127 ** and subsequent parameters to this function. ^Any of these arguments may be
|
|
|
4128 ** NULL, in which case the corresponding element of metadata is omitted.
|
|
|
4129 **
|
|
|
4130 ** ^(<blockquote>
|
|
|
4131 ** <table border="1">
|
|
|
4132 ** <tr><th> Parameter <th> Output<br>Type <th> Description
|
|
|
4133 **
|
|
|
4134 ** <tr><td> 5th <td> const char* <td> Data type
|
|
|
4135 ** <tr><td> 6th <td> const char* <td> Name of default collation sequence
|
|
|
4136 ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
|
|
|
4137 ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
|
|
|
4138 ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
|
|
|
4139 ** </table>
|
|
|
4140 ** </blockquote>)^
|
|
|
4141 **
|
|
|
4142 ** ^The memory pointed to by the character pointers returned for the
|
|
|
4143 ** declaration type and collation sequence is valid only until the next
|
|
|
4144 ** call to any SQLite API function.
|
|
|
4145 **
|
|
|
4146 ** ^If the specified table is actually a view, an [error code] is returned.
|
|
|
4147 **
|
|
|
4148 ** ^If the specified column is "rowid", "oid" or "_rowid_" and an
|
|
|
4149 ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
|
|
|
4150 ** parameters are set for the explicitly declared column. ^(If there is no
|
|
|
4151 ** explicitly declared [INTEGER PRIMARY KEY] column, then the output
|
|
|
4152 ** parameters are set as follows:
|
|
|
4153 **
|
|
|
4154 ** <pre>
|
|
|
4155 ** data type: "INTEGER"
|
|
|
4156 ** collation sequence: "BINARY"
|
|
|
4157 ** not null: 0
|
|
|
4158 ** primary key: 1
|
|
|
4159 ** auto increment: 0
|
|
|
4160 ** </pre>)^
|
|
|
4161 **
|
|
|
4162 ** ^(This function may load one or more schemas from database files. If an
|
|
|
4163 ** error occurs during this process, or if the requested table or column
|
|
|
4164 ** cannot be found, an [error code] is returned and an error message left
|
|
|
4165 ** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^
|
|
|
4166 **
|
|
|
4167 ** ^This API is only available if the library was compiled with the
|
|
|
4168 ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
|
|
|
4169 */
|
|
|
4170 SQLITE_API int sqlite3_table_column_metadata(
|
|
|
4171 sqlite3 *db, /* Connection handle */
|
|
|
4172 const char *zDbName, /* Database name or NULL */
|
|
|
4173 const char *zTableName, /* Table name */
|
|
|
4174 const char *zColumnName, /* Column name */
|
|
|
4175 char const **pzDataType, /* OUTPUT: Declared data type */
|
|
|
4176 char const **pzCollSeq, /* OUTPUT: Collation sequence name */
|
|
|
4177 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
|
|
|
4178 int *pPrimaryKey, /* OUTPUT: True if column part of PK */
|
|
|
4179 int *pAutoinc /* OUTPUT: True if column is auto-increment */
|
|
|
4180 );
|
|
|
4181
|
|
|
4182 /*
|
|
|
4183 ** CAPI3REF: Load An Extension
|
|
|
4184 **
|
|
|
4185 ** ^This interface loads an SQLite extension library from the named file.
|
|
|
4186 **
|
|
|
4187 ** ^The sqlite3_load_extension() interface attempts to load an
|
|
|
4188 ** SQLite extension library contained in the file zFile.
|
|
|
4189 **
|
|
|
4190 ** ^The entry point is zProc.
|
|
|
4191 ** ^zProc may be 0, in which case the name of the entry point
|
|
|
4192 ** defaults to "sqlite3_extension_init".
|
|
|
4193 ** ^The sqlite3_load_extension() interface returns
|
|
|
4194 ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
|
|
|
4195 ** ^If an error occurs and pzErrMsg is not 0, then the
|
|
|
4196 ** [sqlite3_load_extension()] interface shall attempt to
|
|
|
4197 ** fill *pzErrMsg with error message text stored in memory
|
|
|
4198 ** obtained from [sqlite3_malloc()]. The calling function
|
|
|
4199 ** should free this memory by calling [sqlite3_free()].
|
|
|
4200 **
|
|
|
4201 ** ^Extension loading must be enabled using
|
|
|
4202 ** [sqlite3_enable_load_extension()] prior to calling this API,
|
|
|
4203 ** otherwise an error will be returned.
|
|
|
4204 **
|
|
|
4205 ** See also the [load_extension() SQL function].
|
|
|
4206 */
|
|
|
4207 SQLITE_API int sqlite3_load_extension(
|
|
|
4208 sqlite3 *db, /* Load the extension into this database connection */
|
|
|
4209 const char *zFile, /* Name of the shared library containing extension */
|
|
|
4210 const char *zProc, /* Entry point. Derived from zFile if 0 */
|
|
|
4211 char **pzErrMsg /* Put error message here if not 0 */
|
|
|
4212 );
|
|
|
4213
|
|
|
4214 /*
|
|
|
4215 ** CAPI3REF: Enable Or Disable Extension Loading
|
|
|
4216 **
|
|
|
4217 ** ^So as not to open security holes in older applications that are
|
|
|
4218 ** unprepared to deal with extension loading, and as a means of disabling
|
|
|
4219 ** extension loading while evaluating user-entered SQL, the following API
|
|
|
4220 ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
|
|
|
4221 **
|
|
|
4222 ** ^Extension loading is off by default. See ticket #1863.
|
|
|
4223 ** ^Call the sqlite3_enable_load_extension() routine with onoff==1
|
|
|
4224 ** to turn extension loading on and call it with onoff==0 to turn
|
|
|
4225 ** it back off again.
|
|
|
4226 */
|
|
|
4227 SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
|
|
|
4228
|
|
|
4229 /*
|
|
|
4230 ** CAPI3REF: Automatically Load An Extensions
|
|
|
4231 **
|
|
|
4232 ** ^This API can be invoked at program startup in order to register
|
|
|
4233 ** one or more statically linked extensions that will be available
|
|
|
4234 ** to all new [database connections].
|
|
|
4235 **
|
|
|
4236 ** ^(This routine stores a pointer to the extension entry point
|
|
|
4237 ** in an array that is obtained from [sqlite3_malloc()]. That memory
|
|
|
4238 ** is deallocated by [sqlite3_reset_auto_extension()].)^
|
|
|
4239 **
|
|
|
4240 ** ^This function registers an extension entry point that is
|
|
|
4241 ** automatically invoked whenever a new [database connection]
|
|
|
4242 ** is opened using [sqlite3_open()], [sqlite3_open16()],
|
|
|
4243 ** or [sqlite3_open_v2()].
|
|
|
4244 ** ^Duplicate extensions are detected so calling this routine
|
|
|
4245 ** multiple times with the same extension is harmless.
|
|
|
4246 ** ^Automatic extensions apply across all threads.
|
|
|
4247 */
|
|
|
4248 SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
|
|
|
4249
|
|
|
4250 /*
|
|
|
4251 ** CAPI3REF: Reset Automatic Extension Loading
|
|
|
4252 **
|
|
|
4253 ** ^(This function disables all previously registered automatic
|
|
|
4254 ** extensions. It undoes the effect of all prior
|
|
|
4255 ** [sqlite3_auto_extension()] calls.)^
|
|
|
4256 **
|
|
|
4257 ** ^This function disables automatic extensions in all threads.
|
|
|
4258 */
|
|
|
4259 SQLITE_API void sqlite3_reset_auto_extension(void);
|
|
|
4260
|
|
|
4261 /*
|
|
|
4262 ** The interface to the virtual-table mechanism is currently considered
|
|
|
4263 ** to be experimental. The interface might change in incompatible ways.
|
|
|
4264 ** If this is a problem for you, do not use the interface at this time.
|
|
|
4265 **
|
|
|
4266 ** When the virtual-table mechanism stabilizes, we will declare the
|
|
|
4267 ** interface fixed, support it indefinitely, and remove this comment.
|
|
|
4268 */
|
|
|
4269
|
|
|
4270 /*
|
|
|
4271 ** Structures used by the virtual table interface
|
|
|
4272 */
|
|
|
4273 typedef struct sqlite3_vtab sqlite3_vtab;
|
|
|
4274 typedef struct sqlite3_index_info sqlite3_index_info;
|
|
|
4275 typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
|
|
|
4276 typedef struct sqlite3_module sqlite3_module;
|
|
|
4277
|
|
|
4278 /*
|
|
|
4279 ** CAPI3REF: Virtual Table Object
|
|
|
4280 ** KEYWORDS: sqlite3_module {virtual table module}
|
|
|
4281 **
|
|
|
4282 ** This structure, sometimes called a a "virtual table module",
|
|
|
4283 ** defines the implementation of a [virtual tables].
|
|
|
4284 ** This structure consists mostly of methods for the module.
|
|
|
4285 **
|
|
|
4286 ** ^A virtual table module is created by filling in a persistent
|
|
|
4287 ** instance of this structure and passing a pointer to that instance
|
|
|
4288 ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
|
|
|
4289 ** ^The registration remains valid until it is replaced by a different
|
|
|
4290 ** module or until the [database connection] closes. The content
|
|
|
4291 ** of this structure must not change while it is registered with
|
|
|
4292 ** any database connection.
|
|
|
4293 */
|
|
|
4294 struct sqlite3_module {
|
|
|
4295 int iVersion;
|
|
|
4296 int (*xCreate)(sqlite3*, void *pAux,
|
|
|
4297 int argc, const char *const*argv,
|
|
|
4298 sqlite3_vtab **ppVTab, char**);
|
|
|
4299 int (*xConnect)(sqlite3*, void *pAux,
|
|
|
4300 int argc, const char *const*argv,
|
|
|
4301 sqlite3_vtab **ppVTab, char**);
|
|
|
4302 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
|
|
|
4303 int (*xDisconnect)(sqlite3_vtab *pVTab);
|
|
|
4304 int (*xDestroy)(sqlite3_vtab *pVTab);
|
|
|
4305 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
|
|
|
4306 int (*xClose)(sqlite3_vtab_cursor*);
|
|
|
4307 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
|
|
|
4308 int argc, sqlite3_value **argv);
|
|
|
4309 int (*xNext)(sqlite3_vtab_cursor*);
|
|
|
4310 int (*xEof)(sqlite3_vtab_cursor*);
|
|
|
4311 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
|
|
|
4312 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
|
|
|
4313 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
|
|
|
4314 int (*xBegin)(sqlite3_vtab *pVTab);
|
|
|
4315 int (*xSync)(sqlite3_vtab *pVTab);
|
|
|
4316 int (*xCommit)(sqlite3_vtab *pVTab);
|
|
|
4317 int (*xRollback)(sqlite3_vtab *pVTab);
|
|
|
4318 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
|
|
|
4319 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
|
|
|
4320 void **ppArg);
|
|
|
4321 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
|
|
|
4322 };
|
|
|
4323
|
|
|
4324 /*
|
|
|
4325 ** CAPI3REF: Virtual Table Indexing Information
|
|
|
4326 ** KEYWORDS: sqlite3_index_info
|
|
|
4327 **
|
|
|
4328 ** The sqlite3_index_info structure and its substructures is used to
|
|
|
4329 ** pass information into and receive the reply from the [xBestIndex]
|
|
|
4330 ** method of a [virtual table module]. The fields under **Inputs** are the
|
|
|
4331 ** inputs to xBestIndex and are read-only. xBestIndex inserts its
|
|
|
4332 ** results into the **Outputs** fields.
|
|
|
4333 **
|
|
|
4334 ** ^(The aConstraint[] array records WHERE clause constraints of the form:
|
|
|
4335 **
|
|
|
4336 ** <pre>column OP expr</pre>
|
|
|
4337 **
|
|
|
4338 ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is
|
|
|
4339 ** stored in aConstraint[].op.)^ ^(The index of the column is stored in
|
|
|
4340 ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
|
|
|
4341 ** expr on the right-hand side can be evaluated (and thus the constraint
|
|
|
4342 ** is usable) and false if it cannot.)^
|
|
|
4343 **
|
|
|
4344 ** ^The optimizer automatically inverts terms of the form "expr OP column"
|
|
|
4345 ** and makes other simplifications to the WHERE clause in an attempt to
|
|
|
4346 ** get as many WHERE clause terms into the form shown above as possible.
|
|
|
4347 ** ^The aConstraint[] array only reports WHERE clause terms that are
|
|
|
4348 ** relevant to the particular virtual table being queried.
|
|
|
4349 **
|
|
|
4350 ** ^Information about the ORDER BY clause is stored in aOrderBy[].
|
|
|
4351 ** ^Each term of aOrderBy records a column of the ORDER BY clause.
|
|
|
4352 **
|
|
|
4353 ** The [xBestIndex] method must fill aConstraintUsage[] with information
|
|
|
4354 ** about what parameters to pass to xFilter. ^If argvIndex>0 then
|
|
|
4355 ** the right-hand side of the corresponding aConstraint[] is evaluated
|
|
|
4356 ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
|
|
|
4357 ** is true, then the constraint is assumed to be fully handled by the
|
|
|
4358 ** virtual table and is not checked again by SQLite.)^
|
|
|
4359 **
|
|
|
4360 ** ^The idxNum and idxPtr values are recorded and passed into the
|
|
|
4361 ** [xFilter] method.
|
|
|
4362 ** ^[sqlite3_free()] is used to free idxPtr if and only if
|
|
|
4363 ** needToFreeIdxPtr is true.
|
|
|
4364 **
|
|
|
4365 ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
|
|
|
4366 ** the correct order to satisfy the ORDER BY clause so that no separate
|
|
|
4367 ** sorting step is required.
|
|
|
4368 **
|
|
|
4369 ** ^The estimatedCost value is an estimate of the cost of doing the
|
|
|
4370 ** particular lookup. A full scan of a table with N entries should have
|
|
|
4371 ** a cost of N. A binary search of a table of N entries should have a
|
|
|
4372 ** cost of approximately log(N).
|
|
|
4373 */
|
|
|
4374 struct sqlite3_index_info {
|
|
|
4375 /* Inputs */
|
|
|
4376 int nConstraint; /* Number of entries in aConstraint */
|
|
|
4377 struct sqlite3_index_constraint {
|
|
|
4378 int iColumn; /* Column on left-hand side of constraint */
|
|
|
4379 unsigned char op; /* Constraint operator */
|
|
|
4380 unsigned char usable; /* True if this constraint is usable */
|
|
|
4381 int iTermOffset; /* Used internally - xBestIndex should ignore */
|
|
|
4382 } *aConstraint; /* Table of WHERE clause constraints */
|
|
|
4383 int nOrderBy; /* Number of terms in the ORDER BY clause */
|
|
|
4384 struct sqlite3_index_orderby {
|
|
|
4385 int iColumn; /* Column number */
|
|
|
4386 unsigned char desc; /* True for DESC. False for ASC. */
|
|
|
4387 } *aOrderBy; /* The ORDER BY clause */
|
|
|
4388 /* Outputs */
|
|
|
4389 struct sqlite3_index_constraint_usage {
|
|
|
4390 int argvIndex; /* if >0, constraint is part of argv to xFilter */
|
|
|
4391 unsigned char omit; /* Do not code a test for this constraint */
|
|
|
4392 } *aConstraintUsage;
|
|
|
4393 int idxNum; /* Number used to identify the index */
|
|
|
4394 char *idxStr; /* String, possibly obtained from sqlite3_malloc */
|
|
|
4395 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
|
|
|
4396 int orderByConsumed; /* True if output is already ordered */
|
|
|
4397 double estimatedCost; /* Estimated cost of using this index */
|
|
|
4398 };
|
|
|
4399 #define SQLITE_INDEX_CONSTRAINT_EQ 2
|
|
|
4400 #define SQLITE_INDEX_CONSTRAINT_GT 4
|
|
|
4401 #define SQLITE_INDEX_CONSTRAINT_LE 8
|
|
|
4402 #define SQLITE_INDEX_CONSTRAINT_LT 16
|
|
|
4403 #define SQLITE_INDEX_CONSTRAINT_GE 32
|
|
|
4404 #define SQLITE_INDEX_CONSTRAINT_MATCH 64
|
|
|
4405
|
|
|
4406 /*
|
|
|
4407 ** CAPI3REF: Register A Virtual Table Implementation
|
|
|
4408 **
|
|
|
4409 ** ^These routines are used to register a new [virtual table module] name.
|
|
|
4410 ** ^Module names must be registered before
|
|
|
4411 ** creating a new [virtual table] using the module and before using a
|
|
|
4412 ** preexisting [virtual table] for the module.
|
|
|
4413 **
|
|
|
4414 ** ^The module name is registered on the [database connection] specified
|
|
|
4415 ** by the first parameter. ^The name of the module is given by the
|
|
|
4416 ** second parameter. ^The third parameter is a pointer to
|
|
|
4417 ** the implementation of the [virtual table module]. ^The fourth
|
|
|
4418 ** parameter is an arbitrary client data pointer that is passed through
|
|
|
4419 ** into the [xCreate] and [xConnect] methods of the virtual table module
|
|
|
4420 ** when a new virtual table is be being created or reinitialized.
|
|
|
4421 **
|
|
|
4422 ** ^The sqlite3_create_module_v2() interface has a fifth parameter which
|
|
|
4423 ** is a pointer to a destructor for the pClientData. ^SQLite will
|
|
|
4424 ** invoke the destructor function (if it is not NULL) when SQLite
|
|
|
4425 ** no longer needs the pClientData pointer. ^The sqlite3_create_module()
|
|
|
4426 ** interface is equivalent to sqlite3_create_module_v2() with a NULL
|
|
|
4427 ** destructor.
|
|
|
4428 */
|
|
|
4429 SQLITE_API int sqlite3_create_module(
|
|
|
4430 sqlite3 *db, /* SQLite connection to register module with */
|
|
|
4431 const char *zName, /* Name of the module */
|
|
|
4432 const sqlite3_module *p, /* Methods for the module */
|
|
|
4433 void *pClientData /* Client data for xCreate/xConnect */
|
|
|
4434 );
|
|
|
4435 SQLITE_API int sqlite3_create_module_v2(
|
|
|
4436 sqlite3 *db, /* SQLite connection to register module with */
|
|
|
4437 const char *zName, /* Name of the module */
|
|
|
4438 const sqlite3_module *p, /* Methods for the module */
|
|
|
4439 void *pClientData, /* Client data for xCreate/xConnect */
|
|
|
4440 void(*xDestroy)(void*) /* Module destructor function */
|
|
|
4441 );
|
|
|
4442
|
|
|
4443 /*
|
|
|
4444 ** CAPI3REF: Virtual Table Instance Object
|
|
|
4445 ** KEYWORDS: sqlite3_vtab
|
|
|
4446 **
|
|
|
4447 ** Every [virtual table module] implementation uses a subclass
|
|
|
4448 ** of this object to describe a particular instance
|
|
|
4449 ** of the [virtual table]. Each subclass will
|
|
|
4450 ** be tailored to the specific needs of the module implementation.
|
|
|
4451 ** The purpose of this superclass is to define certain fields that are
|
|
|
4452 ** common to all module implementations.
|
|
|
4453 **
|
|
|
4454 ** ^Virtual tables methods can set an error message by assigning a
|
|
|
4455 ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
|
|
|
4456 ** take care that any prior string is freed by a call to [sqlite3_free()]
|
|
|
4457 ** prior to assigning a new string to zErrMsg. ^After the error message
|
|
|
4458 ** is delivered up to the client application, the string will be automatically
|
|
|
4459 ** freed by sqlite3_free() and the zErrMsg field will be zeroed.
|
|
|
4460 */
|
|
|
4461 struct sqlite3_vtab {
|
|
|
4462 const sqlite3_module *pModule; /* The module for this virtual table */
|
|
|
4463 int nRef; /* NO LONGER USED */
|
|
|
4464 char *zErrMsg; /* Error message from sqlite3_mprintf() */
|
|
|
4465 /* Virtual table implementations will typically add additional fields */
|
|
|
4466 };
|
|
|
4467
|
|
|
4468 /*
|
|
|
4469 ** CAPI3REF: Virtual Table Cursor Object
|
|
|
4470 ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
|
|
|
4471 **
|
|
|
4472 ** Every [virtual table module] implementation uses a subclass of the
|
|
|
4473 ** following structure to describe cursors that point into the
|
|
|
4474 ** [virtual table] and are used
|
|
|
4475 ** to loop through the virtual table. Cursors are created using the
|
|
|
4476 ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
|
|
|
4477 ** by the [sqlite3_module.xClose | xClose] method. Cursors are used
|
|
|
4478 ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
|
|
|
4479 ** of the module. Each module implementation will define
|
|
|
4480 ** the content of a cursor structure to suit its own needs.
|
|
|
4481 **
|
|
|
4482 ** This superclass exists in order to define fields of the cursor that
|
|
|
4483 ** are common to all implementations.
|
|
|
4484 */
|
|
|
4485 struct sqlite3_vtab_cursor {
|
|
|
4486 sqlite3_vtab *pVtab; /* Virtual table of this cursor */
|
|
|
4487 /* Virtual table implementations will typically add additional fields */
|
|
|
4488 };
|
|
|
4489
|
|
|
4490 /*
|
|
|
4491 ** CAPI3REF: Declare The Schema Of A Virtual Table
|
|
|
4492 **
|
|
|
4493 ** ^The [xCreate] and [xConnect] methods of a
|
|
|
4494 ** [virtual table module] call this interface
|
|
|
4495 ** to declare the format (the names and datatypes of the columns) of
|
|
|
4496 ** the virtual tables they implement.
|
|
|
4497 */
|
|
|
4498 SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
|
|
|
4499
|
|
|
4500 /*
|
|
|
4501 ** CAPI3REF: Overload A Function For A Virtual Table
|
|
|
4502 **
|
|
|
4503 ** ^(Virtual tables can provide alternative implementations of functions
|
|
|
4504 ** using the [xFindFunction] method of the [virtual table module].
|
|
|
4505 ** But global versions of those functions
|
|
|
4506 ** must exist in order to be overloaded.)^
|
|
|
4507 **
|
|
|
4508 ** ^(This API makes sure a global version of a function with a particular
|
|
|
4509 ** name and number of parameters exists. If no such function exists
|
|
|
4510 ** before this API is called, a new function is created.)^ ^The implementation
|
|
|
4511 ** of the new function always causes an exception to be thrown. So
|
|
|
4512 ** the new function is not good for anything by itself. Its only
|
|
|
4513 ** purpose is to be a placeholder function that can be overloaded
|
|
|
4514 ** by a [virtual table].
|
|
|
4515 */
|
|
|
4516 SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
|
|
|
4517
|
|
|
4518 /*
|
|
|
4519 ** The interface to the virtual-table mechanism defined above (back up
|
|
|
4520 ** to a comment remarkably similar to this one) is currently considered
|
|
|
4521 ** to be experimental. The interface might change in incompatible ways.
|
|
|
4522 ** If this is a problem for you, do not use the interface at this time.
|
|
|
4523 **
|
|
|
4524 ** When the virtual-table mechanism stabilizes, we will declare the
|
|
|
4525 ** interface fixed, support it indefinitely, and remove this comment.
|
|
|
4526 */
|
|
|
4527
|
|
|
4528 /*
|
|
|
4529 ** CAPI3REF: A Handle To An Open BLOB
|
|
|
4530 ** KEYWORDS: {BLOB handle} {BLOB handles}
|
|
|
4531 **
|
|
|
4532 ** An instance of this object represents an open BLOB on which
|
|
|
4533 ** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
|
|
|
4534 ** ^Objects of this type are created by [sqlite3_blob_open()]
|
|
|
4535 ** and destroyed by [sqlite3_blob_close()].
|
|
|
4536 ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
|
|
|
4537 ** can be used to read or write small subsections of the BLOB.
|
|
|
4538 ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
|
|
|
4539 */
|
|
|
4540 typedef struct sqlite3_blob sqlite3_blob;
|
|
|
4541
|
|
|
4542 /*
|
|
|
4543 ** CAPI3REF: Open A BLOB For Incremental I/O
|
|
|
4544 **
|
|
|
4545 ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
|
|
|
4546 ** in row iRow, column zColumn, table zTable in database zDb;
|
|
|
4547 ** in other words, the same BLOB that would be selected by:
|
|
|
4548 **
|
|
|
4549 ** <pre>
|
|
|
4550 ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
|
|
|
4551 ** </pre>)^
|
|
|
4552 **
|
|
|
4553 ** ^If the flags parameter is non-zero, then the BLOB is opened for read
|
|
|
4554 ** and write access. ^If it is zero, the BLOB is opened for read access.
|
|
|
4555 ** ^It is not possible to open a column that is part of an index or primary
|
|
|
4556 ** key for writing. ^If [foreign key constraints] are enabled, it is
|
|
|
4557 ** not possible to open a column that is part of a [child key] for writing.
|
|
|
4558 **
|
|
|
4559 ** ^Note that the database name is not the filename that contains
|
|
|
4560 ** the database but rather the symbolic name of the database that
|
|
|
4561 ** appears after the AS keyword when the database is connected using [ATTACH].
|
|
|
4562 ** ^For the main database file, the database name is "main".
|
|
|
4563 ** ^For TEMP tables, the database name is "temp".
|
|
|
4564 **
|
|
|
4565 ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
|
|
|
4566 ** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
|
|
|
4567 ** to be a null pointer.)^
|
|
|
4568 ** ^This function sets the [database connection] error code and message
|
|
|
4569 ** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
|
|
|
4570 ** functions. ^Note that the *ppBlob variable is always initialized in a
|
|
|
4571 ** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
|
|
|
4572 ** regardless of the success or failure of this routine.
|
|
|
4573 **
|
|
|
4574 ** ^(If the row that a BLOB handle points to is modified by an
|
|
|
4575 ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
|
|
|
4576 ** then the BLOB handle is marked as "expired".
|
|
|
4577 ** This is true if any column of the row is changed, even a column
|
|
|
4578 ** other than the one the BLOB handle is open on.)^
|
|
|
4579 ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
|
|
|
4580 ** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
|
|
|
4581 ** ^(Changes written into a BLOB prior to the BLOB expiring are not
|
|
|
4582 ** rolled back by the expiration of the BLOB. Such changes will eventually
|
|
|
4583 ** commit if the transaction continues to completion.)^
|
|
|
4584 **
|
|
|
4585 ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
|
|
|
4586 ** the opened blob. ^The size of a blob may not be changed by this
|
|
|
4587 ** interface. Use the [UPDATE] SQL command to change the size of a
|
|
|
4588 ** blob.
|
|
|
4589 **
|
|
|
4590 ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
|
|
|
4591 ** and the built-in [zeroblob] SQL function can be used, if desired,
|
|
|
4592 ** to create an empty, zero-filled blob in which to read or write using
|
|
|
4593 ** this interface.
|
|
|
4594 **
|
|
|
4595 ** To avoid a resource leak, every open [BLOB handle] should eventually
|
|
|
4596 ** be released by a call to [sqlite3_blob_close()].
|
|
|
4597 */
|
|
|
4598 SQLITE_API int sqlite3_blob_open(
|
|
|
4599 sqlite3*,
|
|
|
4600 const char *zDb,
|
|
|
4601 const char *zTable,
|
|
|
4602 const char *zColumn,
|
|
|
4603 sqlite3_int64 iRow,
|
|
|
4604 int flags,
|
|
|
4605 sqlite3_blob **ppBlob
|
|
|
4606 );
|
|
|
4607
|
|
|
4608 /*
|
|
|
4609 ** CAPI3REF: Close A BLOB Handle
|
|
|
4610 **
|
|
|
4611 ** ^Closes an open [BLOB handle].
|
|
|
4612 **
|
|
|
4613 ** ^Closing a BLOB shall cause the current transaction to commit
|
|
|
4614 ** if there are no other BLOBs, no pending prepared statements, and the
|
|
|
4615 ** database connection is in [autocommit mode].
|
|
|
4616 ** ^If any writes were made to the BLOB, they might be held in cache
|
|
|
4617 ** until the close operation if they will fit.
|
|
|
4618 **
|
|
|
4619 ** ^(Closing the BLOB often forces the changes
|
|
|
4620 ** out to disk and so if any I/O errors occur, they will likely occur
|
|
|
4621 ** at the time when the BLOB is closed. Any errors that occur during
|
|
|
4622 ** closing are reported as a non-zero return value.)^
|
|
|
4623 **
|
|
|
4624 ** ^(The BLOB is closed unconditionally. Even if this routine returns
|
|
|
4625 ** an error code, the BLOB is still closed.)^
|
|
|
4626 **
|
|
|
4627 ** ^Calling this routine with a null pointer (such as would be returned
|
|
|
4628 ** by a failed call to [sqlite3_blob_open()]) is a harmless no-op.
|
|
|
4629 */
|
|
|
4630 SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
|
|
|
4631
|
|
|
4632 /*
|
|
|
4633 ** CAPI3REF: Return The Size Of An Open BLOB
|
|
|
4634 **
|
|
|
4635 ** ^Returns the size in bytes of the BLOB accessible via the
|
|
|
4636 ** successfully opened [BLOB handle] in its only argument. ^The
|
|
|
4637 ** incremental blob I/O routines can only read or overwriting existing
|
|
|
4638 ** blob content; they cannot change the size of a blob.
|
|
|
4639 **
|
|
|
4640 ** This routine only works on a [BLOB handle] which has been created
|
|
|
4641 ** by a prior successful call to [sqlite3_blob_open()] and which has not
|
|
|
4642 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
|
|
|
4643 ** to this routine results in undefined and probably undesirable behavior.
|
|
|
4644 */
|
|
|
4645 SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
|
|
|
4646
|
|
|
4647 /*
|
|
|
4648 ** CAPI3REF: Read Data From A BLOB Incrementally
|
|
|
4649 **
|
|
|
4650 ** ^(This function is used to read data from an open [BLOB handle] into a
|
|
|
4651 ** caller-supplied buffer. N bytes of data are copied into buffer Z
|
|
|
4652 ** from the open BLOB, starting at offset iOffset.)^
|
|
|
4653 **
|
|
|
4654 ** ^If offset iOffset is less than N bytes from the end of the BLOB,
|
|
|
4655 ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
|
|
|
4656 ** less than zero, [SQLITE_ERROR] is returned and no data is read.
|
|
|
4657 ** ^The size of the blob (and hence the maximum value of N+iOffset)
|
|
|
4658 ** can be determined using the [sqlite3_blob_bytes()] interface.
|
|
|
4659 **
|
|
|
4660 ** ^An attempt to read from an expired [BLOB handle] fails with an
|
|
|
4661 ** error code of [SQLITE_ABORT].
|
|
|
4662 **
|
|
|
4663 ** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
|
|
|
4664 ** Otherwise, an [error code] or an [extended error code] is returned.)^
|
|
|
4665 **
|
|
|
4666 ** This routine only works on a [BLOB handle] which has been created
|
|
|
4667 ** by a prior successful call to [sqlite3_blob_open()] and which has not
|
|
|
4668 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
|
|
|
4669 ** to this routine results in undefined and probably undesirable behavior.
|
|
|
4670 **
|
|
|
4671 ** See also: [sqlite3_blob_write()].
|
|
|
4672 */
|
|
|
4673 SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
|
|
|
4674
|
|
|
4675 /*
|
|
|
4676 ** CAPI3REF: Write Data Into A BLOB Incrementally
|
|
|
4677 **
|
|
|
4678 ** ^This function is used to write data into an open [BLOB handle] from a
|
|
|
4679 ** caller-supplied buffer. ^N bytes of data are copied from the buffer Z
|
|
|
4680 ** into the open BLOB, starting at offset iOffset.
|
|
|
4681 **
|
|
|
4682 ** ^If the [BLOB handle] passed as the first argument was not opened for
|
|
|
4683 ** writing (the flags parameter to [sqlite3_blob_open()] was zero),
|
|
|
4684 ** this function returns [SQLITE_READONLY].
|
|
|
4685 **
|
|
|
4686 ** ^This function may only modify the contents of the BLOB; it is
|
|
|
4687 ** not possible to increase the size of a BLOB using this API.
|
|
|
4688 ** ^If offset iOffset is less than N bytes from the end of the BLOB,
|
|
|
4689 ** [SQLITE_ERROR] is returned and no data is written. ^If N is
|
|
|
4690 ** less than zero [SQLITE_ERROR] is returned and no data is written.
|
|
|
4691 ** The size of the BLOB (and hence the maximum value of N+iOffset)
|
|
|
4692 ** can be determined using the [sqlite3_blob_bytes()] interface.
|
|
|
4693 **
|
|
|
4694 ** ^An attempt to write to an expired [BLOB handle] fails with an
|
|
|
4695 ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
|
|
|
4696 ** before the [BLOB handle] expired are not rolled back by the
|
|
|
4697 ** expiration of the handle, though of course those changes might
|
|
|
4698 ** have been overwritten by the statement that expired the BLOB handle
|
|
|
4699 ** or by other independent statements.
|
|
|
4700 **
|
|
|
4701 ** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
|
|
|
4702 ** Otherwise, an [error code] or an [extended error code] is returned.)^
|
|
|
4703 **
|
|
|
4704 ** This routine only works on a [BLOB handle] which has been created
|
|
|
4705 ** by a prior successful call to [sqlite3_blob_open()] and which has not
|
|
|
4706 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
|
|
|
4707 ** to this routine results in undefined and probably undesirable behavior.
|
|
|
4708 **
|
|
|
4709 ** See also: [sqlite3_blob_read()].
|
|
|
4710 */
|
|
|
4711 SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
|
|
|
4712
|
|
|
4713 /*
|
|
|
4714 ** CAPI3REF: Virtual File System Objects
|
|
|
4715 **
|
|
|
4716 ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
|
|
|
4717 ** that SQLite uses to interact
|
|
|
4718 ** with the underlying operating system. Most SQLite builds come with a
|
|
|
4719 ** single default VFS that is appropriate for the host computer.
|
|
|
4720 ** New VFSes can be registered and existing VFSes can be unregistered.
|
|
|
4721 ** The following interfaces are provided.
|
|
|
4722 **
|
|
|
4723 ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
|
|
|
4724 ** ^Names are case sensitive.
|
|
|
4725 ** ^Names are zero-terminated UTF-8 strings.
|
|
|
4726 ** ^If there is no match, a NULL pointer is returned.
|
|
|
4727 ** ^If zVfsName is NULL then the default VFS is returned.
|
|
|
4728 **
|
|
|
4729 ** ^New VFSes are registered with sqlite3_vfs_register().
|
|
|
4730 ** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
|
|
|
4731 ** ^The same VFS can be registered multiple times without injury.
|
|
|
4732 ** ^To make an existing VFS into the default VFS, register it again
|
|
|
4733 ** with the makeDflt flag set. If two different VFSes with the
|
|
|
4734 ** same name are registered, the behavior is undefined. If a
|
|
|
4735 ** VFS is registered with a name that is NULL or an empty string,
|
|
|
4736 ** then the behavior is undefined.
|
|
|
4737 **
|
|
|
4738 ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
|
|
|
4739 ** ^(If the default VFS is unregistered, another VFS is chosen as
|
|
|
4740 ** the default. The choice for the new VFS is arbitrary.)^
|
|
|
4741 */
|
|
|
4742 SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
|
|
|
4743 SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
|
|
|
4744 SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
|
|
|
4745
|
|
|
4746 /*
|
|
|
4747 ** CAPI3REF: Mutexes
|
|
|
4748 **
|
|
|
4749 ** The SQLite core uses these routines for thread
|
|
|
4750 ** synchronization. Though they are intended for internal
|
|
|
4751 ** use by SQLite, code that links against SQLite is
|
|
|
4752 ** permitted to use any of these routines.
|
|
|
4753 **
|
|
|
4754 ** The SQLite source code contains multiple implementations
|
|
|
4755 ** of these mutex routines. An appropriate implementation
|
|
|
4756 ** is selected automatically at compile-time. ^(The following
|
|
|
4757 ** implementations are available in the SQLite core:
|
|
|
4758 **
|
|
|
4759 ** <ul>
|
|
|
4760 ** <li> SQLITE_MUTEX_OS2
|
|
|
4761 ** <li> SQLITE_MUTEX_PTHREAD
|
|
|
4762 ** <li> SQLITE_MUTEX_W32
|
|
|
4763 ** <li> SQLITE_MUTEX_NOOP
|
|
|
4764 ** </ul>)^
|
|
|
4765 **
|
|
|
4766 ** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
|
|
|
4767 ** that does no real locking and is appropriate for use in
|
|
|
4768 ** a single-threaded application. ^The SQLITE_MUTEX_OS2,
|
|
|
4769 ** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
|
|
|
4770 ** are appropriate for use on OS/2, Unix, and Windows.
|
|
|
4771 **
|
|
|
4772 ** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
|
|
|
4773 ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
|
|
|
4774 ** implementation is included with the library. In this case the
|
|
|
4775 ** application must supply a custom mutex implementation using the
|
|
|
4776 ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
|
|
|
4777 ** before calling sqlite3_initialize() or any other public sqlite3_
|
|
|
4778 ** function that calls sqlite3_initialize().)^
|
|
|
4779 **
|
|
|
4780 ** ^The sqlite3_mutex_alloc() routine allocates a new
|
|
|
4781 ** mutex and returns a pointer to it. ^If it returns NULL
|
|
|
4782 ** that means that a mutex could not be allocated. ^SQLite
|
|
|
4783 ** will unwind its stack and return an error. ^(The argument
|
|
|
4784 ** to sqlite3_mutex_alloc() is one of these integer constants:
|
|
|
4785 **
|
|
|
4786 ** <ul>
|
|
|
4787 ** <li> SQLITE_MUTEX_FAST
|
|
|
4788 ** <li> SQLITE_MUTEX_RECURSIVE
|
|
|
4789 ** <li> SQLITE_MUTEX_STATIC_MASTER
|
|
|
4790 ** <li> SQLITE_MUTEX_STATIC_MEM
|
|
|
4791 ** <li> SQLITE_MUTEX_STATIC_MEM2
|
|
|
4792 ** <li> SQLITE_MUTEX_STATIC_PRNG
|
|
|
4793 ** <li> SQLITE_MUTEX_STATIC_LRU
|
|
|
4794 ** <li> SQLITE_MUTEX_STATIC_LRU2
|
|
|
4795 ** </ul>)^
|
|
|
4796 **
|
|
|
4797 ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
|
|
|
4798 ** cause sqlite3_mutex_alloc() to create
|
|
|
4799 ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
|
|
|
4800 ** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
|
|
|
4801 ** The mutex implementation does not need to make a distinction
|
|
|
4802 ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
|
|
|
4803 ** not want to. ^SQLite will only request a recursive mutex in
|
|
|
4804 ** cases where it really needs one. ^If a faster non-recursive mutex
|
|
|
4805 ** implementation is available on the host platform, the mutex subsystem
|
|
|
4806 ** might return such a mutex in response to SQLITE_MUTEX_FAST.
|
|
|
4807 **
|
|
|
4808 ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
|
|
|
4809 ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
|
|
|
4810 ** a pointer to a static preexisting mutex. ^Six static mutexes are
|
|
|
4811 ** used by the current version of SQLite. Future versions of SQLite
|
|
|
4812 ** may add additional static mutexes. Static mutexes are for internal
|
|
|
4813 ** use by SQLite only. Applications that use SQLite mutexes should
|
|
|
4814 ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
|
|
|
4815 ** SQLITE_MUTEX_RECURSIVE.
|
|
|
4816 **
|
|
|
4817 ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
|
|
|
4818 ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
|
|
|
4819 ** returns a different mutex on every call. ^But for the static
|
|
|
4820 ** mutex types, the same mutex is returned on every call that has
|
|
|
4821 ** the same type number.
|
|
|
4822 **
|
|
|
4823 ** ^The sqlite3_mutex_free() routine deallocates a previously
|
|
|
4824 ** allocated dynamic mutex. ^SQLite is careful to deallocate every
|
|
|
4825 ** dynamic mutex that it allocates. The dynamic mutexes must not be in
|
|
|
4826 ** use when they are deallocated. Attempting to deallocate a static
|
|
|
4827 ** mutex results in undefined behavior. ^SQLite never deallocates
|
|
|
4828 ** a static mutex.
|
|
|
4829 **
|
|
|
4830 ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
|
|
|
4831 ** to enter a mutex. ^If another thread is already within the mutex,
|
|
|
4832 ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
|
|
|
4833 ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
|
|
|
4834 ** upon successful entry. ^(Mutexes created using
|
|
|
4835 ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
|
|
|
4836 ** In such cases the,
|
|
|
4837 ** mutex must be exited an equal number of times before another thread
|
|
|
4838 ** can enter.)^ ^(If the same thread tries to enter any other
|
|
|
4839 ** kind of mutex more than once, the behavior is undefined.
|
|
|
4840 ** SQLite will never exhibit
|
|
|
4841 ** such behavior in its own use of mutexes.)^
|
|
|
4842 **
|
|
|
4843 ** ^(Some systems (for example, Windows 95) do not support the operation
|
|
|
4844 ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
|
|
|
4845 ** will always return SQLITE_BUSY. The SQLite core only ever uses
|
|
|
4846 ** sqlite3_mutex_try() as an optimization so this is acceptable behavior.)^
|
|
|
4847 **
|
|
|
4848 ** ^The sqlite3_mutex_leave() routine exits a mutex that was
|
|
|
4849 ** previously entered by the same thread. ^(The behavior
|
|
|
4850 ** is undefined if the mutex is not currently entered by the
|
|
|
4851 ** calling thread or is not currently allocated. SQLite will
|
|
|
4852 ** never do either.)^
|
|
|
4853 **
|
|
|
4854 ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
|
|
|
4855 ** sqlite3_mutex_leave() is a NULL pointer, then all three routines
|
|
|
4856 ** behave as no-ops.
|
|
|
4857 **
|
|
|
4858 ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
|
|
|
4859 */
|
|
|
4860 SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
|
|
|
4861 SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
|
|
|
4862 SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
|
|
|
4863 SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
|
|
|
4864 SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
|
|
|
4865
|
|
|
4866 /*
|
|
|
4867 ** CAPI3REF: Mutex Methods Object
|
|
|
4868 **
|
|
|
4869 ** An instance of this structure defines the low-level routines
|
|
|
4870 ** used to allocate and use mutexes.
|
|
|
4871 **
|
|
|
4872 ** Usually, the default mutex implementations provided by SQLite are
|
|
|
4873 ** sufficient, however the user has the option of substituting a custom
|
|
|
4874 ** implementation for specialized deployments or systems for which SQLite
|
|
|
4875 ** does not provide a suitable implementation. In this case, the user
|
|
|
4876 ** creates and populates an instance of this structure to pass
|
|
|
4877 ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
|
|
|
4878 ** Additionally, an instance of this structure can be used as an
|
|
|
4879 ** output variable when querying the system for the current mutex
|
|
|
4880 ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
|
|
|
4881 **
|
|
|
4882 ** ^The xMutexInit method defined by this structure is invoked as
|
|
|
4883 ** part of system initialization by the sqlite3_initialize() function.
|
|
|
4884 ** ^The xMutexInit routine is calle by SQLite exactly once for each
|
|
|
4885 ** effective call to [sqlite3_initialize()].
|
|
|
4886 **
|
|
|
4887 ** ^The xMutexEnd method defined by this structure is invoked as
|
|
|
4888 ** part of system shutdown by the sqlite3_shutdown() function. The
|
|
|
4889 ** implementation of this method is expected to release all outstanding
|
|
|
4890 ** resources obtained by the mutex methods implementation, especially
|
|
|
4891 ** those obtained by the xMutexInit method. ^The xMutexEnd()
|
|
|
4892 ** interface is invoked exactly once for each call to [sqlite3_shutdown()].
|
|
|
4893 **
|
|
|
4894 ** ^(The remaining seven methods defined by this structure (xMutexAlloc,
|
|
|
4895 ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
|
|
|
4896 ** xMutexNotheld) implement the following interfaces (respectively):
|
|
|
4897 **
|
|
|
4898 ** <ul>
|
|
|
4899 ** <li> [sqlite3_mutex_alloc()] </li>
|
|
|
4900 ** <li> [sqlite3_mutex_free()] </li>
|
|
|
4901 ** <li> [sqlite3_mutex_enter()] </li>
|
|
|
4902 ** <li> [sqlite3_mutex_try()] </li>
|
|
|
4903 ** <li> [sqlite3_mutex_leave()] </li>
|
|
|
4904 ** <li> [sqlite3_mutex_held()] </li>
|
|
|
4905 ** <li> [sqlite3_mutex_notheld()] </li>
|
|
|
4906 ** </ul>)^
|
|
|
4907 **
|
|
|
4908 ** The only difference is that the public sqlite3_XXX functions enumerated
|
|
|
4909 ** above silently ignore any invocations that pass a NULL pointer instead
|
|
|
4910 ** of a valid mutex handle. The implementations of the methods defined
|
|
|
4911 ** by this structure are not required to handle this case, the results
|
|
|
4912 ** of passing a NULL pointer instead of a valid mutex handle are undefined
|
|
|
4913 ** (i.e. it is acceptable to provide an implementation that segfaults if
|
|
|
4914 ** it is passed a NULL pointer).
|
|
|
4915 **
|
|
|
4916 ** The xMutexInit() method must be threadsafe. ^It must be harmless to
|
|
|
4917 ** invoke xMutexInit() mutiple times within the same process and without
|
|
|
4918 ** intervening calls to xMutexEnd(). Second and subsequent calls to
|
|
|
4919 ** xMutexInit() must be no-ops.
|
|
|
4920 **
|
|
|
4921 ** ^xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
|
|
|
4922 ** and its associates). ^Similarly, xMutexAlloc() must not use SQLite memory
|
|
|
4923 ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
|
|
|
4924 ** memory allocation for a fast or recursive mutex.
|
|
|
4925 **
|
|
|
4926 ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
|
|
|
4927 ** called, but only if the prior call to xMutexInit returned SQLITE_OK.
|
|
|
4928 ** If xMutexInit fails in any way, it is expected to clean up after itself
|
|
|
4929 ** prior to returning.
|
|
|
4930 */
|
|
|
4931 typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
|
|
|
4932 struct sqlite3_mutex_methods {
|
|
|
4933 int (*xMutexInit)(void);
|
|
|
4934 int (*xMutexEnd)(void);
|
|
|
4935 sqlite3_mutex *(*xMutexAlloc)(int);
|
|
|
4936 void (*xMutexFree)(sqlite3_mutex *);
|
|
|
4937 void (*xMutexEnter)(sqlite3_mutex *);
|
|
|
4938 int (*xMutexTry)(sqlite3_mutex *);
|
|
|
4939 void (*xMutexLeave)(sqlite3_mutex *);
|
|
|
4940 int (*xMutexHeld)(sqlite3_mutex *);
|
|
|
4941 int (*xMutexNotheld)(sqlite3_mutex *);
|
|
|
4942 };
|
|
|
4943
|
|
|
4944 /*
|
|
|
4945 ** CAPI3REF: Mutex Verification Routines
|
|
|
4946 **
|
|
|
4947 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
|
|
|
4948 ** are intended for use inside assert() statements. ^The SQLite core
|
|
|
4949 ** never uses these routines except inside an assert() and applications
|
|
|
4950 ** are advised to follow the lead of the core. ^The SQLite core only
|
|
|
4951 ** provides implementations for these routines when it is compiled
|
|
|
4952 ** with the SQLITE_DEBUG flag. ^External mutex implementations
|
|
|
4953 ** are only required to provide these routines if SQLITE_DEBUG is
|
|
|
4954 ** defined and if NDEBUG is not defined.
|
|
|
4955 **
|
|
|
4956 ** ^These routines should return true if the mutex in their argument
|
|
|
4957 ** is held or not held, respectively, by the calling thread.
|
|
|
4958 **
|
|
|
4959 ** ^The implementation is not required to provided versions of these
|
|
|
4960 ** routines that actually work. If the implementation does not provide working
|
|
|
4961 ** versions of these routines, it should at least provide stubs that always
|
|
|
4962 ** return true so that one does not get spurious assertion failures.
|
|
|
4963 **
|
|
|
4964 ** ^If the argument to sqlite3_mutex_held() is a NULL pointer then
|
|
|
4965 ** the routine should return 1. This seems counter-intuitive since
|
|
|
4966 ** clearly the mutex cannot be held if it does not exist. But the
|
|
|
4967 ** the reason the mutex does not exist is because the build is not
|
|
|
4968 ** using mutexes. And we do not want the assert() containing the
|
|
|
4969 ** call to sqlite3_mutex_held() to fail, so a non-zero return is
|
|
|
4970 ** the appropriate thing to do. ^The sqlite3_mutex_notheld()
|
|
|
4971 ** interface should also return 1 when given a NULL pointer.
|
|
|
4972 */
|
|
|
4973 #ifndef NDEBUG
|
|
|
4974 SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
|
|
|
4975 SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
|
|
|
4976 #endif
|
|
|
4977
|
|
|
4978 /*
|
|
|
4979 ** CAPI3REF: Mutex Types
|
|
|
4980 **
|
|
|
4981 ** The [sqlite3_mutex_alloc()] interface takes a single argument
|
|
|
4982 ** which is one of these integer constants.
|
|
|
4983 **
|
|
|
4984 ** The set of static mutexes may change from one SQLite release to the
|
|
|
4985 ** next. Applications that override the built-in mutex logic must be
|
|
|
4986 ** prepared to accommodate additional static mutexes.
|
|
|
4987 */
|
|
|
4988 #define SQLITE_MUTEX_FAST 0
|
|
|
4989 #define SQLITE_MUTEX_RECURSIVE 1
|
|
|
4990 #define SQLITE_MUTEX_STATIC_MASTER 2
|
|
|
4991 #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
|
|
|
4992 #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
|
|
|
4993 #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
|
|
|
4994 #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
|
|
|
4995 #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
|
|
|
4996 #define SQLITE_MUTEX_STATIC_LRU2 7 /* lru page list */
|
|
|
4997
|
|
|
4998 /*
|
|
|
4999 ** CAPI3REF: Retrieve the mutex for a database connection
|
|
|
5000 **
|
|
|
5001 ** ^This interface returns a pointer the [sqlite3_mutex] object that
|
|
|
5002 ** serializes access to the [database connection] given in the argument
|
|
|
5003 ** when the [threading mode] is Serialized.
|
|
|
5004 ** ^If the [threading mode] is Single-thread or Multi-thread then this
|
|
|
5005 ** routine returns a NULL pointer.
|
|
|
5006 */
|
|
|
5007 SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
|
|
|
5008
|
|
|
5009 /*
|
|
|
5010 ** CAPI3REF: Low-Level Control Of Database Files
|
|
|
5011 **
|
|
|
5012 ** ^The [sqlite3_file_control()] interface makes a direct call to the
|
|
|
5013 ** xFileControl method for the [sqlite3_io_methods] object associated
|
|
|
5014 ** with a particular database identified by the second argument. ^The
|
|
|
5015 ** name of the database "main" for the main database or "temp" for the
|
|
|
5016 ** TEMP database, or the name that appears after the AS keyword for
|
|
|
5017 ** databases that are added using the [ATTACH] SQL command.
|
|
|
5018 ** ^A NULL pointer can be used in place of "main" to refer to the
|
|
|
5019 ** main database file.
|
|
|
5020 ** ^The third and fourth parameters to this routine
|
|
|
5021 ** are passed directly through to the second and third parameters of
|
|
|
5022 ** the xFileControl method. ^The return value of the xFileControl
|
|
|
5023 ** method becomes the return value of this routine.
|
|
|
5024 **
|
|
|
5025 ** ^If the second parameter (zDbName) does not match the name of any
|
|
|
5026 ** open database file, then SQLITE_ERROR is returned. ^This error
|
|
|
5027 ** code is not remembered and will not be recalled by [sqlite3_errcode()]
|
|
|
5028 ** or [sqlite3_errmsg()]. The underlying xFileControl method might
|
|
|
5029 ** also return SQLITE_ERROR. There is no way to distinguish between
|
|
|
5030 ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
|
|
|
5031 ** xFileControl method.
|
|
|
5032 **
|
|
|
5033 ** See also: [SQLITE_FCNTL_LOCKSTATE]
|
|
|
5034 */
|
|
|
5035 SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
|
|
|
5036
|
|
|
5037 /*
|
|
|
5038 ** CAPI3REF: Testing Interface
|
|
|
5039 **
|
|
|
5040 ** ^The sqlite3_test_control() interface is used to read out internal
|
|
|
5041 ** state of SQLite and to inject faults into SQLite for testing
|
|
|
5042 ** purposes. ^The first parameter is an operation code that determines
|
|
|
5043 ** the number, meaning, and operation of all subsequent parameters.
|
|
|
5044 **
|
|
|
5045 ** This interface is not for use by applications. It exists solely
|
|
|
5046 ** for verifying the correct operation of the SQLite library. Depending
|
|
|
5047 ** on how the SQLite library is compiled, this interface might not exist.
|
|
|
5048 **
|
|
|
5049 ** The details of the operation codes, their meanings, the parameters
|
|
|
5050 ** they take, and what they do are all subject to change without notice.
|
|
|
5051 ** Unlike most of the SQLite API, this function is not guaranteed to
|
|
|
5052 ** operate consistently from one release to the next.
|
|
|
5053 */
|
|
|
5054 SQLITE_API int sqlite3_test_control(int op, ...);
|
|
|
5055
|
|
|
5056 /*
|
|
|
5057 ** CAPI3REF: Testing Interface Operation Codes
|
|
|
5058 **
|
|
|
5059 ** These constants are the valid operation code parameters used
|
|
|
5060 ** as the first argument to [sqlite3_test_control()].
|
|
|
5061 **
|
|
|
5062 ** These parameters and their meanings are subject to change
|
|
|
5063 ** without notice. These values are for testing purposes only.
|
|
|
5064 ** Applications should not use any of these parameters or the
|
|
|
5065 ** [sqlite3_test_control()] interface.
|
|
|
5066 */
|
|
|
5067 #define SQLITE_TESTCTRL_FIRST 5
|
|
|
5068 #define SQLITE_TESTCTRL_PRNG_SAVE 5
|
|
|
5069 #define SQLITE_TESTCTRL_PRNG_RESTORE 6
|
|
|
5070 #define SQLITE_TESTCTRL_PRNG_RESET 7
|
|
|
5071 #define SQLITE_TESTCTRL_BITVEC_TEST 8
|
|
|
5072 #define SQLITE_TESTCTRL_FAULT_INSTALL 9
|
|
|
5073 #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
|
|
|
5074 #define SQLITE_TESTCTRL_PENDING_BYTE 11
|
|
|
5075 #define SQLITE_TESTCTRL_ASSERT 12
|
|
|
5076 #define SQLITE_TESTCTRL_ALWAYS 13
|
|
|
5077 #define SQLITE_TESTCTRL_RESERVE 14
|
|
|
5078 #define SQLITE_TESTCTRL_OPTIMIZATIONS 15
|
|
|
5079 #define SQLITE_TESTCTRL_ISKEYWORD 16
|
|
|
5080 #define SQLITE_TESTCTRL_PGHDRSZ 17
|
|
|
5081 #define SQLITE_TESTCTRL_LAST 17
|
|
|
5082
|
|
|
5083 /*
|
|
|
5084 ** CAPI3REF: SQLite Runtime Status
|
|
|
5085 **
|
|
|
5086 ** ^This interface is used to retrieve runtime status information
|
|
|
5087 ** about the preformance of SQLite, and optionally to reset various
|
|
|
5088 ** highwater marks. ^The first argument is an integer code for
|
|
|
5089 ** the specific parameter to measure. ^(Recognized integer codes
|
|
|
5090 ** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].)^
|
|
|
5091 ** ^The current value of the parameter is returned into *pCurrent.
|
|
|
5092 ** ^The highest recorded value is returned in *pHighwater. ^If the
|
|
|
5093 ** resetFlag is true, then the highest record value is reset after
|
|
|
5094 ** *pHighwater is written. ^(Some parameters do not record the highest
|
|
|
5095 ** value. For those parameters
|
|
|
5096 ** nothing is written into *pHighwater and the resetFlag is ignored.)^
|
|
|
5097 ** ^(Other parameters record only the highwater mark and not the current
|
|
|
5098 ** value. For these latter parameters nothing is written into *pCurrent.)^
|
|
|
5099 **
|
|
|
5100 ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
|
|
|
5101 ** non-zero [error code] on failure.
|
|
|
5102 **
|
|
|
5103 ** This routine is threadsafe but is not atomic. This routine can be
|
|
|
5104 ** called while other threads are running the same or different SQLite
|
|
|
5105 ** interfaces. However the values returned in *pCurrent and
|
|
|
5106 ** *pHighwater reflect the status of SQLite at different points in time
|
|
|
5107 ** and it is possible that another thread might change the parameter
|
|
|
5108 ** in between the times when *pCurrent and *pHighwater are written.
|
|
|
5109 **
|
|
|
5110 ** See also: [sqlite3_db_status()]
|
|
|
5111 */
|
|
|
5112 SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
|
|
|
5113
|
|
|
5114
|
|
|
5115 /*
|
|
|
5116 ** CAPI3REF: Status Parameters
|
|
|
5117 **
|
|
|
5118 ** These integer constants designate various run-time status parameters
|
|
|
5119 ** that can be returned by [sqlite3_status()].
|
|
|
5120 **
|
|
|
5121 ** <dl>
|
|
|
5122 ** ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
|
|
|
5123 ** <dd>This parameter is the current amount of memory checked out
|
|
|
5124 ** using [sqlite3_malloc()], either directly or indirectly. The
|
|
|
5125 ** figure includes calls made to [sqlite3_malloc()] by the application
|
|
|
5126 ** and internal memory usage by the SQLite library. Scratch memory
|
|
|
5127 ** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
|
|
|
5128 ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
|
|
|
5129 ** this parameter. The amount returned is the sum of the allocation
|
|
|
5130 ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
|
|
|
5131 **
|
|
|
5132 ** ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
|
|
|
5133 ** <dd>This parameter records the largest memory allocation request
|
|
|
5134 ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
|
|
|
5135 ** internal equivalents). Only the value returned in the
|
|
|
5136 ** *pHighwater parameter to [sqlite3_status()] is of interest.
|
|
|
5137 ** The value written into the *pCurrent parameter is undefined.</dd>)^
|
|
|
5138 **
|
|
|
5139 ** ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
|
|
|
5140 ** <dd>This parameter returns the number of pages used out of the
|
|
|
5141 ** [pagecache memory allocator] that was configured using
|
|
|
5142 ** [SQLITE_CONFIG_PAGECACHE]. The
|
|
|
5143 ** value returned is in pages, not in bytes.</dd>)^
|
|
|
5144 **
|
|
|
5145 ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
|
|
|
5146 ** <dd>This parameter returns the number of bytes of page cache
|
|
|
5147 ** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
|
|
|
5148 ** buffer and where forced to overflow to [sqlite3_malloc()]. The
|
|
|
5149 ** returned value includes allocations that overflowed because they
|
|
|
5150 ** where too large (they were larger than the "sz" parameter to
|
|
|
5151 ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
|
|
|
5152 ** no space was left in the page cache.</dd>)^
|
|
|
5153 **
|
|
|
5154 ** ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
|
|
|
5155 ** <dd>This parameter records the largest memory allocation request
|
|
|
5156 ** handed to [pagecache memory allocator]. Only the value returned in the
|
|
|
5157 ** *pHighwater parameter to [sqlite3_status()] is of interest.
|
|
|
5158 ** The value written into the *pCurrent parameter is undefined.</dd>)^
|
|
|
5159 **
|
|
|
5160 ** ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>
|
|
|
5161 ** <dd>This parameter returns the number of allocations used out of the
|
|
|
5162 ** [scratch memory allocator] configured using
|
|
|
5163 ** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
|
|
|
5164 ** in bytes. Since a single thread may only have one scratch allocation
|
|
|
5165 ** outstanding at time, this parameter also reports the number of threads
|
|
|
5166 ** using scratch memory at the same time.</dd>)^
|
|
|
5167 **
|
|
|
5168 ** ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
|
|
|
5169 ** <dd>This parameter returns the number of bytes of scratch memory
|
|
|
5170 ** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
|
|
|
5171 ** buffer and where forced to overflow to [sqlite3_malloc()]. The values
|
|
|
5172 ** returned include overflows because the requested allocation was too
|
|
|
5173 ** larger (that is, because the requested allocation was larger than the
|
|
|
5174 ** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
|
|
|
5175 ** slots were available.
|
|
|
5176 ** </dd>)^
|
|
|
5177 **
|
|
|
5178 ** ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
|
|
|
5179 ** <dd>This parameter records the largest memory allocation request
|
|
|
5180 ** handed to [scratch memory allocator]. Only the value returned in the
|
|
|
5181 ** *pHighwater parameter to [sqlite3_status()] is of interest.
|
|
|
5182 ** The value written into the *pCurrent parameter is undefined.</dd>)^
|
|
|
5183 **
|
|
|
5184 ** ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
|
|
|
5185 ** <dd>This parameter records the deepest parser stack. It is only
|
|
|
5186 ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
|
|
|
5187 ** </dl>
|
|
|
5188 **
|
|
|
5189 ** New status parameters may be added from time to time.
|
|
|
5190 */
|
|
|
5191 #define SQLITE_STATUS_MEMORY_USED 0
|
|
|
5192 #define SQLITE_STATUS_PAGECACHE_USED 1
|
|
|
5193 #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
|
|
|
5194 #define SQLITE_STATUS_SCRATCH_USED 3
|
|
|
5195 #define SQLITE_STATUS_SCRATCH_OVERFLOW 4
|
|
|
5196 #define SQLITE_STATUS_MALLOC_SIZE 5
|
|
|
5197 #define SQLITE_STATUS_PARSER_STACK 6
|
|
|
5198 #define SQLITE_STATUS_PAGECACHE_SIZE 7
|
|
|
5199 #define SQLITE_STATUS_SCRATCH_SIZE 8
|
|
|
5200
|
|
|
5201 /*
|
|
|
5202 ** CAPI3REF: Database Connection Status
|
|
|
5203 **
|
|
|
5204 ** ^This interface is used to retrieve runtime status information
|
|
|
5205 ** about a single [database connection]. ^The first argument is the
|
|
|
5206 ** database connection object to be interrogated. ^The second argument
|
|
|
5207 ** is an integer constant, taken from the set of
|
|
|
5208 ** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros, that
|
|
|
5209 ** determiness the parameter to interrogate. The set of
|
|
|
5210 ** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros is likely
|
|
|
5211 ** to grow in future releases of SQLite.
|
|
|
5212 **
|
|
|
5213 ** ^The current value of the requested parameter is written into *pCur
|
|
|
5214 ** and the highest instantaneous value is written into *pHiwtr. ^If
|
|
|
5215 ** the resetFlg is true, then the highest instantaneous value is
|
|
|
5216 ** reset back down to the current value.
|
|
|
5217 **
|
|
|
5218 ** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
|
|
|
5219 */
|
|
|
5220 SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
|
|
|
5221
|
|
|
5222 /*
|
|
|
5223 ** CAPI3REF: Status Parameters for database connections
|
|
|
5224 **
|
|
|
5225 ** These constants are the available integer "verbs" that can be passed as
|
|
|
5226 ** the second argument to the [sqlite3_db_status()] interface.
|
|
|
5227 **
|
|
|
5228 ** New verbs may be added in future releases of SQLite. Existing verbs
|
|
|
5229 ** might be discontinued. Applications should check the return code from
|
|
|
5230 ** [sqlite3_db_status()] to make sure that the call worked.
|
|
|
5231 ** The [sqlite3_db_status()] interface will return a non-zero error code
|
|
|
5232 ** if a discontinued or unsupported verb is invoked.
|
|
|
5233 **
|
|
|
5234 ** <dl>
|
|
|
5235 ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
|
|
|
5236 ** <dd>This parameter returns the number of lookaside memory slots currently
|
|
|
5237 ** checked out.</dd>)^
|
|
|
5238 **
|
|
|
5239 ** <dt>SQLITE_DBSTATUS_CACHE_USED</dt>
|
|
|
5240 ** <dd>^This parameter returns the approximate number of of bytes of heap
|
|
|
5241 ** memory used by all pager caches associated with the database connection.
|
|
|
5242 ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
|
|
|
5243 ** </dd>
|
|
|
5244 ** </dl>
|
|
|
5245 */
|
|
|
5246 #define SQLITE_DBSTATUS_LOOKASIDE_USED 0
|
|
|
5247 #define SQLITE_DBSTATUS_CACHE_USED 1
|
|
|
5248 #define SQLITE_DBSTATUS_MAX 1 /* Largest defined DBSTATUS */
|
|
|
5249
|
|
|
5250
|
|
|
5251 /*
|
|
|
5252 ** CAPI3REF: Prepared Statement Status
|
|
|
5253 **
|
|
|
5254 ** ^(Each prepared statement maintains various
|
|
|
5255 ** [SQLITE_STMTSTATUS_SORT | counters] that measure the number
|
|
|
5256 ** of times it has performed specific operations.)^ These counters can
|
|
|
5257 ** be used to monitor the performance characteristics of the prepared
|
|
|
5258 ** statements. For example, if the number of table steps greatly exceeds
|
|
|
5259 ** the number of table searches or result rows, that would tend to indicate
|
|
|
5260 ** that the prepared statement is using a full table scan rather than
|
|
|
5261 ** an index.
|
|
|
5262 **
|
|
|
5263 ** ^(This interface is used to retrieve and reset counter values from
|
|
|
5264 ** a [prepared statement]. The first argument is the prepared statement
|
|
|
5265 ** object to be interrogated. The second argument
|
|
|
5266 ** is an integer code for a specific [SQLITE_STMTSTATUS_SORT | counter]
|
|
|
5267 ** to be interrogated.)^
|
|
|
5268 ** ^The current value of the requested counter is returned.
|
|
|
5269 ** ^If the resetFlg is true, then the counter is reset to zero after this
|
|
|
5270 ** interface call returns.
|
|
|
5271 **
|
|
|
5272 ** See also: [sqlite3_status()] and [sqlite3_db_status()].
|
|
|
5273 */
|
|
|
5274 SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
|
|
|
5275
|
|
|
5276 /*
|
|
|
5277 ** CAPI3REF: Status Parameters for prepared statements
|
|
|
5278 **
|
|
|
5279 ** These preprocessor macros define integer codes that name counter
|
|
|
5280 ** values associated with the [sqlite3_stmt_status()] interface.
|
|
|
5281 ** The meanings of the various counters are as follows:
|
|
|
5282 **
|
|
|
5283 ** <dl>
|
|
|
5284 ** <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
|
|
|
5285 ** <dd>^This is the number of times that SQLite has stepped forward in
|
|
|
5286 ** a table as part of a full table scan. Large numbers for this counter
|
|
|
5287 ** may indicate opportunities for performance improvement through
|
|
|
5288 ** careful use of indices.</dd>
|
|
|
5289 **
|
|
|
5290 ** <dt>SQLITE_STMTSTATUS_SORT</dt>
|
|
|
5291 ** <dd>^This is the number of sort operations that have occurred.
|
|
|
5292 ** A non-zero value in this counter may indicate an opportunity to
|
|
|
5293 ** improvement performance through careful use of indices.</dd>
|
|
|
5294 **
|
|
|
5295 ** <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
|
|
|
5296 ** <dd>^This is the number of rows inserted into transient indices that
|
|
|
5297 ** were created automatically in order to help joins run faster.
|
|
|
5298 ** A non-zero value in this counter may indicate an opportunity to
|
|
|
5299 ** improvement performance by adding permanent indices that do not
|
|
|
5300 ** need to be reinitialized each time the statement is run.</dd>
|
|
|
5301 **
|
|
|
5302 ** </dl>
|
|
|
5303 */
|
|
|
5304 #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
|
|
|
5305 #define SQLITE_STMTSTATUS_SORT 2
|
|
|
5306 #define SQLITE_STMTSTATUS_AUTOINDEX 3
|
|
|
5307
|
|
|
5308 /*
|
|
|
5309 ** CAPI3REF: Custom Page Cache Object
|
|
|
5310 **
|
|
|
5311 ** The sqlite3_pcache type is opaque. It is implemented by
|
|
|
5312 ** the pluggable module. The SQLite core has no knowledge of
|
|
|
5313 ** its size or internal structure and never deals with the
|
|
|
5314 ** sqlite3_pcache object except by holding and passing pointers
|
|
|
5315 ** to the object.
|
|
|
5316 **
|
|
|
5317 ** See [sqlite3_pcache_methods] for additional information.
|
|
|
5318 */
|
|
|
5319 typedef struct sqlite3_pcache sqlite3_pcache;
|
|
|
5320
|
|
|
5321 /*
|
|
|
5322 ** CAPI3REF: Application Defined Page Cache.
|
|
|
5323 ** KEYWORDS: {page cache}
|
|
|
5324 **
|
|
|
5325 ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can
|
|
|
5326 ** register an alternative page cache implementation by passing in an
|
|
|
5327 ** instance of the sqlite3_pcache_methods structure.)^ The majority of the
|
|
|
5328 ** heap memory used by SQLite is used by the page cache to cache data read
|
|
|
5329 ** from, or ready to be written to, the database file. By implementing a
|
|
|
5330 ** custom page cache using this API, an application can control more
|
|
|
5331 ** precisely the amount of memory consumed by SQLite, the way in which
|
|
|
5332 ** that memory is allocated and released, and the policies used to
|
|
|
5333 ** determine exactly which parts of a database file are cached and for
|
|
|
5334 ** how long.
|
|
|
5335 **
|
|
|
5336 ** ^(The contents of the sqlite3_pcache_methods structure are copied to an
|
|
|
5337 ** internal buffer by SQLite within the call to [sqlite3_config]. Hence
|
|
|
5338 ** the application may discard the parameter after the call to
|
|
|
5339 ** [sqlite3_config()] returns.)^
|
|
|
5340 **
|
|
|
5341 ** ^The xInit() method is called once for each call to [sqlite3_initialize()]
|
|
|
5342 ** (usually only once during the lifetime of the process). ^(The xInit()
|
|
|
5343 ** method is passed a copy of the sqlite3_pcache_methods.pArg value.)^
|
|
|
5344 ** ^The xInit() method can set up up global structures and/or any mutexes
|
|
|
5345 ** required by the custom page cache implementation.
|
|
|
5346 **
|
|
|
5347 ** ^The xShutdown() method is called from within [sqlite3_shutdown()],
|
|
|
5348 ** if the application invokes this API. It can be used to clean up
|
|
|
5349 ** any outstanding resources before process shutdown, if required.
|
|
|
5350 **
|
|
|
5351 ** ^SQLite holds a [SQLITE_MUTEX_RECURSIVE] mutex when it invokes
|
|
|
5352 ** the xInit method, so the xInit method need not be threadsafe. ^The
|
|
|
5353 ** xShutdown method is only called from [sqlite3_shutdown()] so it does
|
|
|
5354 ** not need to be threadsafe either. All other methods must be threadsafe
|
|
|
5355 ** in multithreaded applications.
|
|
|
5356 **
|
|
|
5357 ** ^SQLite will never invoke xInit() more than once without an intervening
|
|
|
5358 ** call to xShutdown().
|
|
|
5359 **
|
|
|
5360 ** ^The xCreate() method is used to construct a new cache instance. SQLite
|
|
|
5361 ** will typically create one cache instance for each open database file,
|
|
|
5362 ** though this is not guaranteed. ^The
|
|
|
5363 ** first parameter, szPage, is the size in bytes of the pages that must
|
|
|
5364 ** be allocated by the cache. ^szPage will not be a power of two. ^szPage
|
|
|
5365 ** will the page size of the database file that is to be cached plus an
|
|
|
5366 ** increment (here called "R") of about 100 or 200. ^SQLite will use the
|
|
|
5367 ** extra R bytes on each page to store metadata about the underlying
|
|
|
5368 ** database page on disk. The value of R depends
|
|
|
5369 ** on the SQLite version, the target platform, and how SQLite was compiled.
|
|
|
5370 ** ^R is constant for a particular build of SQLite. ^The second argument to
|
|
|
5371 ** xCreate(), bPurgeable, is true if the cache being created will
|
|
|
5372 ** be used to cache database pages of a file stored on disk, or
|
|
|
5373 ** false if it is used for an in-memory database. ^The cache implementation
|
|
|
5374 ** does not have to do anything special based with the value of bPurgeable;
|
|
|
5375 ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
|
|
|
5376 ** never invoke xUnpin() except to deliberately delete a page.
|
|
|
5377 ** ^In other words, a cache created with bPurgeable set to false will
|
|
|
5378 ** never contain any unpinned pages.
|
|
|
5379 **
|
|
|
5380 ** ^(The xCachesize() method may be called at any time by SQLite to set the
|
|
|
5381 ** suggested maximum cache-size (number of pages stored by) the cache
|
|
|
5382 ** instance passed as the first argument. This is the value configured using
|
|
|
5383 ** the SQLite "[PRAGMA cache_size]" command.)^ ^As with the bPurgeable
|
|
|
5384 ** parameter, the implementation is not required to do anything with this
|
|
|
5385 ** value; it is advisory only.
|
|
|
5386 **
|
|
|
5387 ** ^The xPagecount() method should return the number of pages currently
|
|
|
5388 ** stored in the cache.
|
|
|
5389 **
|
|
|
5390 ** ^The xFetch() method is used to fetch a page and return a pointer to it.
|
|
|
5391 ** ^A 'page', in this context, is a buffer of szPage bytes aligned at an
|
|
|
5392 ** 8-byte boundary. ^The page to be fetched is determined by the key. ^The
|
|
|
5393 ** mimimum key value is 1. After it has been retrieved using xFetch, the page
|
|
|
5394 ** is considered to be "pinned".
|
|
|
5395 **
|
|
|
5396 ** ^If the requested page is already in the page cache, then the page cache
|
|
|
5397 ** implementation must return a pointer to the page buffer with its content
|
|
|
5398 ** intact. ^(If the requested page is not already in the cache, then the
|
|
|
5399 ** behavior of the cache implementation is determined by the value of the
|
|
|
5400 ** createFlag parameter passed to xFetch, according to the following table:
|
|
|
5401 **
|
|
|
5402 ** <table border=1 width=85% align=center>
|
|
|
5403 ** <tr><th> createFlag <th> Behaviour when page is not already in cache
|
|
|
5404 ** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
|
|
|
5405 ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
|
|
|
5406 ** Otherwise return NULL.
|
|
|
5407 ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
|
|
|
5408 ** NULL if allocating a new page is effectively impossible.
|
|
|
5409 ** </table>)^
|
|
|
5410 **
|
|
|
5411 ** SQLite will normally invoke xFetch() with a createFlag of 0 or 1. If
|
|
|
5412 ** a call to xFetch() with createFlag==1 returns NULL, then SQLite will
|
|
|
5413 ** attempt to unpin one or more cache pages by spilling the content of
|
|
|
5414 ** pinned pages to disk and synching the operating system disk cache. After
|
|
|
5415 ** attempting to unpin pages, the xFetch() method will be invoked again with
|
|
|
5416 ** a createFlag of 2.
|
|
|
5417 **
|
|
|
5418 ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
|
|
|
5419 ** as its second argument. ^(If the third parameter, discard, is non-zero,
|
|
|
5420 ** then the page should be evicted from the cache. In this case SQLite
|
|
|
5421 ** assumes that the next time the page is retrieved from the cache using
|
|
|
5422 ** the xFetch() method, it will be zeroed.)^ ^If the discard parameter is
|
|
|
5423 ** zero, then the page is considered to be unpinned. ^The cache implementation
|
|
|
5424 ** may choose to evict unpinned pages at any time.
|
|
|
5425 **
|
|
|
5426 ** ^(The cache is not required to perform any reference counting. A single
|
|
|
5427 ** call to xUnpin() unpins the page regardless of the number of prior calls
|
|
|
5428 ** to xFetch().)^
|
|
|
5429 **
|
|
|
5430 ** ^The xRekey() method is used to change the key value associated with the
|
|
|
5431 ** page passed as the second argument from oldKey to newKey. ^If the cache
|
|
|
5432 ** previously contains an entry associated with newKey, it should be
|
|
|
5433 ** discarded. ^Any prior cache entry associated with newKey is guaranteed not
|
|
|
5434 ** to be pinned.
|
|
|
5435 **
|
|
|
5436 ** ^When SQLite calls the xTruncate() method, the cache must discard all
|
|
|
5437 ** existing cache entries with page numbers (keys) greater than or equal
|
|
|
5438 ** to the value of the iLimit parameter passed to xTruncate(). ^If any
|
|
|
5439 ** of these pages are pinned, they are implicitly unpinned, meaning that
|
|
|
5440 ** they can be safely discarded.
|
|
|
5441 **
|
|
|
5442 ** ^The xDestroy() method is used to delete a cache allocated by xCreate().
|
|
|
5443 ** All resources associated with the specified cache should be freed. ^After
|
|
|
5444 ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
|
|
|
5445 ** handle invalid, and will not use it with any other sqlite3_pcache_methods
|
|
|
5446 ** functions.
|
|
|
5447 */
|
|
|
5448 typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
|
|
|
5449 struct sqlite3_pcache_methods {
|
|
|
5450 void *pArg;
|
|
|
5451 int (*xInit)(void*);
|
|
|
5452 void (*xShutdown)(void*);
|
|
|
5453 sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
|
|
|
5454 void (*xCachesize)(sqlite3_pcache*, int nCachesize);
|
|
|
5455 int (*xPagecount)(sqlite3_pcache*);
|
|
|
5456 void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
|
|
|
5457 void (*xUnpin)(sqlite3_pcache*, void*, int discard);
|
|
|
5458 void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
|
|
|
5459 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
|
|
|
5460 void (*xDestroy)(sqlite3_pcache*);
|
|
|
5461 };
|
|
|
5462
|
|
|
5463 /*
|
|
|
5464 ** CAPI3REF: Online Backup Object
|
|
|
5465 **
|
|
|
5466 ** The sqlite3_backup object records state information about an ongoing
|
|
|
5467 ** online backup operation. ^The sqlite3_backup object is created by
|
|
|
5468 ** a call to [sqlite3_backup_init()] and is destroyed by a call to
|
|
|
5469 ** [sqlite3_backup_finish()].
|
|
|
5470 **
|
|
|
5471 ** See Also: [Using the SQLite Online Backup API]
|
|
|
5472 */
|
|
|
5473 typedef struct sqlite3_backup sqlite3_backup;
|
|
|
5474
|
|
|
5475 /*
|
|
|
5476 ** CAPI3REF: Online Backup API.
|
|
|
5477 **
|
|
|
5478 ** The backup API copies the content of one database into another.
|
|
|
5479 ** It is useful either for creating backups of databases or
|
|
|
5480 ** for copying in-memory databases to or from persistent files.
|
|
|
5481 **
|
|
|
5482 ** See Also: [Using the SQLite Online Backup API]
|
|
|
5483 **
|
|
|
5484 ** ^Exclusive access is required to the destination database for the
|
|
|
5485 ** duration of the operation. ^However the source database is only
|
|
|
5486 ** read-locked while it is actually being read; it is not locked
|
|
|
5487 ** continuously for the entire backup operation. ^Thus, the backup may be
|
|
|
5488 ** performed on a live source database without preventing other users from
|
|
|
5489 ** reading or writing to the source database while the backup is underway.
|
|
|
5490 **
|
|
|
5491 ** ^(To perform a backup operation:
|
|
|
5492 ** <ol>
|
|
|
5493 ** <li><b>sqlite3_backup_init()</b> is called once to initialize the
|
|
|
5494 ** backup,
|
|
|
5495 ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
|
|
|
5496 ** the data between the two databases, and finally
|
|
|
5497 ** <li><b>sqlite3_backup_finish()</b> is called to release all resources
|
|
|
5498 ** associated with the backup operation.
|
|
|
5499 ** </ol>)^
|
|
|
5500 ** There should be exactly one call to sqlite3_backup_finish() for each
|
|
|
5501 ** successful call to sqlite3_backup_init().
|
|
|
5502 **
|
|
|
5503 ** <b>sqlite3_backup_init()</b>
|
|
|
5504 **
|
|
|
5505 ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
|
|
|
5506 ** [database connection] associated with the destination database
|
|
|
5507 ** and the database name, respectively.
|
|
|
5508 ** ^The database name is "main" for the main database, "temp" for the
|
|
|
5509 ** temporary database, or the name specified after the AS keyword in
|
|
|
5510 ** an [ATTACH] statement for an attached database.
|
|
|
5511 ** ^The S and M arguments passed to
|
|
|
5512 ** sqlite3_backup_init(D,N,S,M) identify the [database connection]
|
|
|
5513 ** and database name of the source database, respectively.
|
|
|
5514 ** ^The source and destination [database connections] (parameters S and D)
|
|
|
5515 ** must be different or else sqlite3_backup_init(D,N,S,M) will file with
|
|
|
5516 ** an error.
|
|
|
5517 **
|
|
|
5518 ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
|
|
|
5519 ** returned and an error code and error message are store3d in the
|
|
|
5520 ** destination [database connection] D.
|
|
|
5521 ** ^The error code and message for the failed call to sqlite3_backup_init()
|
|
|
5522 ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
|
|
|
5523 ** [sqlite3_errmsg16()] functions.
|
|
|
5524 ** ^A successful call to sqlite3_backup_init() returns a pointer to an
|
|
|
5525 ** [sqlite3_backup] object.
|
|
|
5526 ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
|
|
|
5527 ** sqlite3_backup_finish() functions to perform the specified backup
|
|
|
5528 ** operation.
|
|
|
5529 **
|
|
|
5530 ** <b>sqlite3_backup_step()</b>
|
|
|
5531 **
|
|
|
5532 ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
|
|
|
5533 ** the source and destination databases specified by [sqlite3_backup] object B.
|
|
|
5534 ** ^If N is negative, all remaining source pages are copied.
|
|
|
5535 ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
|
|
|
5536 ** are still more pages to be copied, then the function resturns [SQLITE_OK].
|
|
|
5537 ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
|
|
|
5538 ** from source to destination, then it returns [SQLITE_DONE].
|
|
|
5539 ** ^If an error occurs while running sqlite3_backup_step(B,N),
|
|
|
5540 ** then an [error code] is returned. ^As well as [SQLITE_OK] and
|
|
|
5541 ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
|
|
|
5542 ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
|
|
|
5543 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
|
|
|
5544 **
|
|
|
5545 ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
|
|
|
5546 ** <ol>
|
|
|
5547 ** <li> the destination database was opened read-only, or
|
|
|
5548 ** <li> the destination database is using write-ahead-log journaling
|
|
|
5549 ** and the destination and source page sizes differ, or
|
|
|
5550 ** <li> The destination database is an in-memory database and the
|
|
|
5551 ** destination and source page sizes differ.
|
|
|
5552 ** </ol>)^
|
|
|
5553 **
|
|
|
5554 ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
|
|
|
5555 ** the [sqlite3_busy_handler | busy-handler function]
|
|
|
5556 ** is invoked (if one is specified). ^If the
|
|
|
5557 ** busy-handler returns non-zero before the lock is available, then
|
|
|
5558 ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
|
|
|
5559 ** sqlite3_backup_step() can be retried later. ^If the source
|
|
|
5560 ** [database connection]
|
|
|
5561 ** is being used to write to the source database when sqlite3_backup_step()
|
|
|
5562 ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
|
|
|
5563 ** case the call to sqlite3_backup_step() can be retried later on. ^(If
|
|
|
5564 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
|
|
|
5565 ** [SQLITE_READONLY] is returned, then
|
|
|
5566 ** there is no point in retrying the call to sqlite3_backup_step(). These
|
|
|
5567 ** errors are considered fatal.)^ The application must accept
|
|
|
5568 ** that the backup operation has failed and pass the backup operation handle
|
|
|
5569 ** to the sqlite3_backup_finish() to release associated resources.
|
|
|
5570 **
|
|
|
5571 ** ^The first call to sqlite3_backup_step() obtains an exclusive lock
|
|
|
5572 ** on the destination file. ^The exclusive lock is not released until either
|
|
|
5573 ** sqlite3_backup_finish() is called or the backup operation is complete
|
|
|
5574 ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
|
|
|
5575 ** sqlite3_backup_step() obtains a [shared lock] on the source database that
|
|
|
5576 ** lasts for the duration of the sqlite3_backup_step() call.
|
|
|
5577 ** ^Because the source database is not locked between calls to
|
|
|
5578 ** sqlite3_backup_step(), the source database may be modified mid-way
|
|
|
5579 ** through the backup process. ^If the source database is modified by an
|
|
|
5580 ** external process or via a database connection other than the one being
|
|
|
5581 ** used by the backup operation, then the backup will be automatically
|
|
|
5582 ** restarted by the next call to sqlite3_backup_step(). ^If the source
|
|
|
5583 ** database is modified by the using the same database connection as is used
|
|
|
5584 ** by the backup operation, then the backup database is automatically
|
|
|
5585 ** updated at the same time.
|
|
|
5586 **
|
|
|
5587 ** <b>sqlite3_backup_finish()</b>
|
|
|
5588 **
|
|
|
5589 ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
|
|
|
5590 ** application wishes to abandon the backup operation, the application
|
|
|
5591 ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
|
|
|
5592 ** ^The sqlite3_backup_finish() interfaces releases all
|
|
|
5593 ** resources associated with the [sqlite3_backup] object.
|
|
|
5594 ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
|
|
|
5595 ** active write-transaction on the destination database is rolled back.
|
|
|
5596 ** The [sqlite3_backup] object is invalid
|
|
|
5597 ** and may not be used following a call to sqlite3_backup_finish().
|
|
|
5598 **
|
|
|
5599 ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
|
|
|
5600 ** sqlite3_backup_step() errors occurred, regardless or whether or not
|
|
|
5601 ** sqlite3_backup_step() completed.
|
|
|
5602 ** ^If an out-of-memory condition or IO error occurred during any prior
|
|
|
5603 ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
|
|
|
5604 ** sqlite3_backup_finish() returns the corresponding [error code].
|
|
|
5605 **
|
|
|
5606 ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
|
|
|
5607 ** is not a permanent error and does not affect the return value of
|
|
|
5608 ** sqlite3_backup_finish().
|
|
|
5609 **
|
|
|
5610 ** <b>sqlite3_backup_remaining(), sqlite3_backup_pagecount()</b>
|
|
|
5611 **
|
|
|
5612 ** ^Each call to sqlite3_backup_step() sets two values inside
|
|
|
5613 ** the [sqlite3_backup] object: the number of pages still to be backed
|
|
|
5614 ** up and the total number of pages in the source databae file.
|
|
|
5615 ** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
|
|
|
5616 ** retrieve these two values, respectively.
|
|
|
5617 **
|
|
|
5618 ** ^The values returned by these functions are only updated by
|
|
|
5619 ** sqlite3_backup_step(). ^If the source database is modified during a backup
|
|
|
5620 ** operation, then the values are not updated to account for any extra
|
|
|
5621 ** pages that need to be updated or the size of the source database file
|
|
|
5622 ** changing.
|
|
|
5623 **
|
|
|
5624 ** <b>Concurrent Usage of Database Handles</b>
|
|
|
5625 **
|
|
|
5626 ** ^The source [database connection] may be used by the application for other
|
|
|
5627 ** purposes while a backup operation is underway or being initialized.
|
|
|
5628 ** ^If SQLite is compiled and configured to support threadsafe database
|
|
|
5629 ** connections, then the source database connection may be used concurrently
|
|
|
5630 ** from within other threads.
|
|
|
5631 **
|
|
|
5632 ** However, the application must guarantee that the destination
|
|
|
5633 ** [database connection] is not passed to any other API (by any thread) after
|
|
|
5634 ** sqlite3_backup_init() is called and before the corresponding call to
|
|
|
5635 ** sqlite3_backup_finish(). SQLite does not currently check to see
|
|
|
5636 ** if the application incorrectly accesses the destination [database connection]
|
|
|
5637 ** and so no error code is reported, but the operations may malfunction
|
|
|
5638 ** nevertheless. Use of the destination database connection while a
|
|
|
5639 ** backup is in progress might also also cause a mutex deadlock.
|
|
|
5640 **
|
|
|
5641 ** If running in [shared cache mode], the application must
|
|
|
5642 ** guarantee that the shared cache used by the destination database
|
|
|
5643 ** is not accessed while the backup is running. In practice this means
|
|
|
5644 ** that the application must guarantee that the disk file being
|
|
|
5645 ** backed up to is not accessed by any connection within the process,
|
|
|
5646 ** not just the specific connection that was passed to sqlite3_backup_init().
|
|
|
5647 **
|
|
|
5648 ** The [sqlite3_backup] object itself is partially threadsafe. Multiple
|
|
|
5649 ** threads may safely make multiple concurrent calls to sqlite3_backup_step().
|
|
|
5650 ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
|
|
|
5651 ** APIs are not strictly speaking threadsafe. If they are invoked at the
|
|
|
5652 ** same time as another thread is invoking sqlite3_backup_step() it is
|
|
|
5653 ** possible that they return invalid values.
|
|
|
5654 */
|
|
|
5655 SQLITE_API sqlite3_backup *sqlite3_backup_init(
|
|
|
5656 sqlite3 *pDest, /* Destination database handle */
|
|
|
5657 const char *zDestName, /* Destination database name */
|
|
|
5658 sqlite3 *pSource, /* Source database handle */
|
|
|
5659 const char *zSourceName /* Source database name */
|
|
|
5660 );
|
|
|
5661 SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
|
|
|
5662 SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
|
|
|
5663 SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
|
|
|
5664 SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
|
|
|
5665
|
|
|
5666 /*
|
|
|
5667 ** CAPI3REF: Unlock Notification
|
|
|
5668 **
|
|
|
5669 ** ^When running in shared-cache mode, a database operation may fail with
|
|
|
5670 ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
|
|
|
5671 ** individual tables within the shared-cache cannot be obtained. See
|
|
|
5672 ** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
|
|
|
5673 ** ^This API may be used to register a callback that SQLite will invoke
|
|
|
5674 ** when the connection currently holding the required lock relinquishes it.
|
|
|
5675 ** ^This API is only available if the library was compiled with the
|
|
|
5676 ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
|
|
|
5677 **
|
|
|
5678 ** See Also: [Using the SQLite Unlock Notification Feature].
|
|
|
5679 **
|
|
|
5680 ** ^Shared-cache locks are released when a database connection concludes
|
|
|
5681 ** its current transaction, either by committing it or rolling it back.
|
|
|
5682 **
|
|
|
5683 ** ^When a connection (known as the blocked connection) fails to obtain a
|
|
|
5684 ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
|
|
|
5685 ** identity of the database connection (the blocking connection) that
|
|
|
5686 ** has locked the required resource is stored internally. ^After an
|
|
|
5687 ** application receives an SQLITE_LOCKED error, it may call the
|
|
|
5688 ** sqlite3_unlock_notify() method with the blocked connection handle as
|
|
|
5689 ** the first argument to register for a callback that will be invoked
|
|
|
5690 ** when the blocking connections current transaction is concluded. ^The
|
|
|
5691 ** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
|
|
|
5692 ** call that concludes the blocking connections transaction.
|
|
|
5693 **
|
|
|
5694 ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
|
|
|
5695 ** there is a chance that the blocking connection will have already
|
|
|
5696 ** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
|
|
|
5697 ** If this happens, then the specified callback is invoked immediately,
|
|
|
5698 ** from within the call to sqlite3_unlock_notify().)^
|
|
|
5699 **
|
|
|
5700 ** ^If the blocked connection is attempting to obtain a write-lock on a
|
|
|
5701 ** shared-cache table, and more than one other connection currently holds
|
|
|
5702 ** a read-lock on the same table, then SQLite arbitrarily selects one of
|
|
|
5703 ** the other connections to use as the blocking connection.
|
|
|
5704 **
|
|
|
5705 ** ^(There may be at most one unlock-notify callback registered by a
|
|
|
5706 ** blocked connection. If sqlite3_unlock_notify() is called when the
|
|
|
5707 ** blocked connection already has a registered unlock-notify callback,
|
|
|
5708 ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
|
|
|
5709 ** called with a NULL pointer as its second argument, then any existing
|
|
|
5710 ** unlock-notify callback is cancelled. ^The blocked connections
|
|
|
5711 ** unlock-notify callback may also be canceled by closing the blocked
|
|
|
5712 ** connection using [sqlite3_close()].
|
|
|
5713 **
|
|
|
5714 ** The unlock-notify callback is not reentrant. If an application invokes
|
|
|
5715 ** any sqlite3_xxx API functions from within an unlock-notify callback, a
|
|
|
5716 ** crash or deadlock may be the result.
|
|
|
5717 **
|
|
|
5718 ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
|
|
|
5719 ** returns SQLITE_OK.
|
|
|
5720 **
|
|
|
5721 ** <b>Callback Invocation Details</b>
|
|
|
5722 **
|
|
|
5723 ** When an unlock-notify callback is registered, the application provides a
|
|
|
5724 ** single void* pointer that is passed to the callback when it is invoked.
|
|
|
5725 ** However, the signature of the callback function allows SQLite to pass
|
|
|
5726 ** it an array of void* context pointers. The first argument passed to
|
|
|
5727 ** an unlock-notify callback is a pointer to an array of void* pointers,
|
|
|
5728 ** and the second is the number of entries in the array.
|
|
|
5729 **
|
|
|
5730 ** When a blocking connections transaction is concluded, there may be
|
|
|
5731 ** more than one blocked connection that has registered for an unlock-notify
|
|
|
5732 ** callback. ^If two or more such blocked connections have specified the
|
|
|
5733 ** same callback function, then instead of invoking the callback function
|
|
|
5734 ** multiple times, it is invoked once with the set of void* context pointers
|
|
|
5735 ** specified by the blocked connections bundled together into an array.
|
|
|
5736 ** This gives the application an opportunity to prioritize any actions
|
|
|
5737 ** related to the set of unblocked database connections.
|
|
|
5738 **
|
|
|
5739 ** <b>Deadlock Detection</b>
|
|
|
5740 **
|
|
|
5741 ** Assuming that after registering for an unlock-notify callback a
|
|
|
5742 ** database waits for the callback to be issued before taking any further
|
|
|
5743 ** action (a reasonable assumption), then using this API may cause the
|
|
|
5744 ** application to deadlock. For example, if connection X is waiting for
|
|
|
5745 ** connection Y's transaction to be concluded, and similarly connection
|
|
|
5746 ** Y is waiting on connection X's transaction, then neither connection
|
|
|
5747 ** will proceed and the system may remain deadlocked indefinitely.
|
|
|
5748 **
|
|
|
5749 ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
|
|
|
5750 ** detection. ^If a given call to sqlite3_unlock_notify() would put the
|
|
|
5751 ** system in a deadlocked state, then SQLITE_LOCKED is returned and no
|
|
|
5752 ** unlock-notify callback is registered. The system is said to be in
|
|
|
5753 ** a deadlocked state if connection A has registered for an unlock-notify
|
|
|
5754 ** callback on the conclusion of connection B's transaction, and connection
|
|
|
5755 ** B has itself registered for an unlock-notify callback when connection
|
|
|
5756 ** A's transaction is concluded. ^Indirect deadlock is also detected, so
|
|
|
5757 ** the system is also considered to be deadlocked if connection B has
|
|
|
5758 ** registered for an unlock-notify callback on the conclusion of connection
|
|
|
5759 ** C's transaction, where connection C is waiting on connection A. ^Any
|
|
|
5760 ** number of levels of indirection are allowed.
|
|
|
5761 **
|
|
|
5762 ** <b>The "DROP TABLE" Exception</b>
|
|
|
5763 **
|
|
|
5764 ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
|
|
|
5765 ** always appropriate to call sqlite3_unlock_notify(). There is however,
|
|
|
5766 ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
|
|
|
5767 ** SQLite checks if there are any currently executing SELECT statements
|
|
|
5768 ** that belong to the same connection. If there are, SQLITE_LOCKED is
|
|
|
5769 ** returned. In this case there is no "blocking connection", so invoking
|
|
|
5770 ** sqlite3_unlock_notify() results in the unlock-notify callback being
|
|
|
5771 ** invoked immediately. If the application then re-attempts the "DROP TABLE"
|
|
|
5772 ** or "DROP INDEX" query, an infinite loop might be the result.
|
|
|
5773 **
|
|
|
5774 ** One way around this problem is to check the extended error code returned
|
|
|
5775 ** by an sqlite3_step() call. ^(If there is a blocking connection, then the
|
|
|
5776 ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
|
|
|
5777 ** the special "DROP TABLE/INDEX" case, the extended error code is just
|
|
|
5778 ** SQLITE_LOCKED.)^
|
|
|
5779 */
|
|
|
5780 SQLITE_API int sqlite3_unlock_notify(
|
|
|
5781 sqlite3 *pBlocked, /* Waiting connection */
|
|
|
5782 void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
|
|
|
5783 void *pNotifyArg /* Argument to pass to xNotify */
|
|
|
5784 );
|
|
|
5785
|
|
|
5786
|
|
|
5787 /*
|
|
|
5788 ** CAPI3REF: String Comparison
|
|
|
5789 **
|
|
|
5790 ** ^The [sqlite3_strnicmp()] API allows applications and extensions to
|
|
|
5791 ** compare the contents of two buffers containing UTF-8 strings in a
|
|
|
5792 ** case-indendent fashion, using the same definition of case independence
|
|
|
5793 ** that SQLite uses internally when comparing identifiers.
|
|
|
5794 */
|
|
|
5795 SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
|
|
|
5796
|
|
|
5797 /*
|
|
|
5798 ** CAPI3REF: Error Logging Interface
|
|
|
5799 **
|
|
|
5800 ** ^The [sqlite3_log()] interface writes a message into the error log
|
|
|
5801 ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
|
|
|
5802 ** ^If logging is enabled, the zFormat string and subsequent arguments are
|
|
|
5803 ** used with [sqlite3_snprintf()] to generate the final output string.
|
|
|
5804 **
|
|
|
5805 ** The sqlite3_log() interface is intended for use by extensions such as
|
|
|
5806 ** virtual tables, collating functions, and SQL functions. While there is
|
|
|
5807 ** nothing to prevent an application from calling sqlite3_log(), doing so
|
|
|
5808 ** is considered bad form.
|
|
|
5809 **
|
|
|
5810 ** The zFormat string must not be NULL.
|
|
|
5811 **
|
|
|
5812 ** To avoid deadlocks and other threading problems, the sqlite3_log() routine
|
|
|
5813 ** will not use dynamically allocated memory. The log message is stored in
|
|
|
5814 ** a fixed-length buffer on the stack. If the log message is longer than
|
|
|
5815 ** a few hundred characters, it will be truncated to the length of the
|
|
|
5816 ** buffer.
|
|
|
5817 */
|
|
|
5818 SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
|
|
|
5819
|
|
|
5820 /*
|
|
|
5821 ** CAPI3REF: Write-Ahead Log Commit Hook
|
|
|
5822 **
|
|
|
5823 ** ^The [sqlite3_wal_hook()] function is used to register a callback that
|
|
|
5824 ** will be invoked each time a database connection commits data to a
|
|
|
5825 ** [write-ahead log] (i.e. whenever a transaction is committed in
|
|
|
5826 ** [journal_mode | journal_mode=WAL mode]).
|
|
|
5827 **
|
|
|
5828 ** ^The callback is invoked by SQLite after the commit has taken place and
|
|
|
5829 ** the associated write-lock on the database released, so the implementation
|
|
|
5830 ** may read, write or [checkpoint] the database as required.
|
|
|
5831 **
|
|
|
5832 ** ^The first parameter passed to the callback function when it is invoked
|
|
|
5833 ** is a copy of the third parameter passed to sqlite3_wal_hook() when
|
|
|
5834 ** registering the callback. ^The second is a copy of the database handle.
|
|
|
5835 ** ^The third parameter is the name of the database that was written to -
|
|
|
5836 ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
|
|
|
5837 ** is the number of pages currently in the write-ahead log file,
|
|
|
5838 ** including those that were just committed.
|
|
|
5839 **
|
|
|
5840 ** The callback function should normally return [SQLITE_OK]. ^If an error
|
|
|
5841 ** code is returned, that error will propagate back up through the
|
|
|
5842 ** SQLite code base to cause the statement that provoked the callback
|
|
|
5843 ** to report an error, though the commit will have still occurred. If the
|
|
|
5844 ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
|
|
|
5845 ** that does not correspond to any valid SQLite error code, the results
|
|
|
5846 ** are undefined.
|
|
|
5847 **
|
|
|
5848 ** A single database handle may have at most a single write-ahead log callback
|
|
|
5849 ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
|
|
|
5850 ** previously registered write-ahead log callback. ^Note that the
|
|
|
5851 ** [sqlite3_wal_autocheckpoint()] interface and the
|
|
|
5852 ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
|
|
|
5853 ** those overwrite any prior [sqlite3_wal_hook()] settings.
|
|
|
5854 */
|
|
|
5855 SQLITE_API void *sqlite3_wal_hook(
|
|
|
5856 sqlite3*,
|
|
|
5857 int(*)(void *,sqlite3*,const char*,int),
|
|
|
5858 void*
|
|
|
5859 );
|
|
|
5860
|
|
|
5861 /*
|
|
|
5862 ** CAPI3REF: Configure an auto-checkpoint
|
|
|
5863 **
|
|
|
5864 ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
|
|
|
5865 ** [sqlite3_wal_hook()] that causes any database on [database connection] D
|
|
|
5866 ** to automatically [checkpoint]
|
|
|
5867 ** after committing a transaction if there are N or
|
|
|
5868 ** more frames in the [write-ahead log] file. ^Passing zero or
|
|
|
5869 ** a negative value as the nFrame parameter disables automatic
|
|
|
5870 ** checkpoints entirely.
|
|
|
5871 **
|
|
|
5872 ** ^The callback registered by this function replaces any existing callback
|
|
|
5873 ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
|
|
|
5874 ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
|
|
|
5875 ** configured by this function.
|
|
|
5876 **
|
|
|
5877 ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
|
|
|
5878 ** from SQL.
|
|
|
5879 **
|
|
|
5880 ** ^Every new [database connection] defaults to having the auto-checkpoint
|
|
|
5881 ** enabled with a threshold of 1000 pages. The use of this interface
|
|
|
5882 ** is only necessary if the default setting is found to be suboptimal
|
|
|
5883 ** for a particular application.
|
|
|
5884 */
|
|
|
5885 SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
|
|
|
5886
|
|
|
5887 /*
|
|
|
5888 ** CAPI3REF: Checkpoint a database
|
|
|
5889 **
|
|
|
5890 ** ^The [sqlite3_wal_checkpoint(D,X)] interface causes database named X
|
|
|
5891 ** on [database connection] D to be [checkpointed]. ^If X is NULL or an
|
|
|
5892 ** empty string, then a checkpoint is run on all databases of
|
|
|
5893 ** connection D. ^If the database connection D is not in
|
|
|
5894 ** [WAL | write-ahead log mode] then this interface is a harmless no-op.
|
|
|
5895 **
|
|
|
5896 ** ^The [wal_checkpoint pragma] can be used to invoke this interface
|
|
|
5897 ** from SQL. ^The [sqlite3_wal_autocheckpoint()] interface and the
|
|
|
5898 ** [wal_autocheckpoint pragma] can be used to cause this interface to be
|
|
|
5899 ** run whenever the WAL reaches a certain size threshold.
|
|
|
5900 */
|
|
|
5901 SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
|
|
|
5902
|
|
|
5903 /*
|
|
|
5904 ** Undo the hack that converts floating point types to integer for
|
|
|
5905 ** builds on processors without floating point support.
|
|
|
5906 */
|
|
|
5907 #ifdef SQLITE_OMIT_FLOATING_POINT
|
|
|
5908 # undef double
|
|
|
5909 #endif
|
|
|
5910
|
|
|
5911 #ifdef __cplusplus
|
|
|
5912 } /* End of the 'extern "C"' block */
|
|
|
5913 #endif
|
|
|
5914 #endif
|
|
|
5915
|
