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diff --git a/www/c3ref/c_config_covering_index_scan.html b/www/c3ref/c_config_covering_index_scan.html new file mode 100644 index 0000000..fb67580 --- /dev/null +++ b/www/c3ref/c_config_covering_index_scan.html @@ -0,0 +1,552 @@ +<!DOCTYPE html> +<html><head> +<meta name="viewport" content="width=device-width, initial-scale=1.0"> +<meta http-equiv="content-type" content="text/html; charset=UTF-8"> +<link href="../sqlite.css" rel="stylesheet"> +<title>Configuration Options</title> +<!-- path=../ --> +</head> +<body> +<div class=nosearch> +<a href="../index.html"> +<img class="logo" src="../images/sqlite370_banner.gif" alt="SQLite" border="0"> +</a> +<div><!-- IE hack to prevent disappearing logo --></div> +<div class="tagline desktoponly"> +Small. Fast. Reliable.<br>Choose any three. +</div> +<div class="menu mainmenu"> +<ul> +<li><a href="../index.html">Home</a> +<li class='mobileonly'><a href="javascript:void(0)" onclick='toggle_div("submenu")'>Menu</a> +<li class='wideonly'><a href='../about.html'>About</a> +<li class='desktoponly'><a href="../docs.html">Documentation</a> +<li class='desktoponly'><a href="../download.html">Download</a> +<li class='wideonly'><a href='../copyright.html'>License</a> +<li class='desktoponly'><a href="../support.html">Support</a> +<li class='desktoponly'><a href="../prosupport.html">Purchase</a> +<li class='search' id='search_menubutton'> +<a href="javascript:void(0)" onclick='toggle_search()'>Search</a> +</ul> +</div> +<div class="menu submenu" id="submenu"> +<ul> +<li><a href='../about.html'>About</a> +<li><a href='../docs.html'>Documentation</a> +<li><a href='../download.html'>Download</a> +<li><a href='../support.html'>Support</a> +<li><a href='../prosupport.html'>Purchase</a> +</ul> +</div> +<div class="searchmenu" id="searchmenu"> +<form method="GET" action="../search"> +<select name="s" id="searchtype"> +<option value="d">Search Documentation</option> +<option value="c">Search Changelog</option> +</select> +<input type="text" name="q" id="searchbox" value=""> +<input type="submit" value="Go"> +</form> +</div> +</div> +<script> +function toggle_div(nm) { +var w = document.getElementById(nm); +if( w.style.display=="block" ){ +w.style.display = "none"; +}else{ +w.style.display = "block"; +} +} +function toggle_search() { +var w = document.getElementById("searchmenu"); +if( w.style.display=="block" ){ +w.style.display = "none"; +} else { +w.style.display = "block"; +setTimeout(function(){ +document.getElementById("searchbox").focus() +}, 30); +} +} +function div_off(nm){document.getElementById(nm).style.display="none";} +window.onbeforeunload = function(e){div_off("submenu");} +/* Disable the Search feature if we are not operating from CGI, since */ +/* Search is accomplished using CGI and will not work without it. */ +if( !location.origin || !location.origin.match || !location.origin.match(/http/) ){ +document.getElementById("search_menubutton").style.display = "none"; +} +/* Used by the Hide/Show button beside syntax diagrams, to toggle the */ +function hideorshow(btn,obj){ +var x = document.getElementById(obj); +var b = document.getElementById(btn); +if( x.style.display!='none' ){ +x.style.display = 'none'; +b.innerHTML='show'; +}else{ +x.style.display = ''; +b.innerHTML='hide'; +} +return false; +} +var antiRobot = 0; +function antiRobotGo(){ +if( antiRobot!=3 ) return; +antiRobot = 7; +var j = document.getElementById("mtimelink"); +if(j && j.hasAttribute("data-href")) j.href=j.getAttribute("data-href"); +} +function antiRobotDefense(){ +document.body.onmousedown=function(){ +antiRobot |= 2; +antiRobotGo(); +document.body.onmousedown=null; +} +document.body.onmousemove=function(){ +antiRobot |= 2; +antiRobotGo(); +document.body.onmousemove=null; +} +setTimeout(function(){ +antiRobot |= 1; +antiRobotGo(); +}, 100) +antiRobotGo(); +} +antiRobotDefense(); +</script> +<!-- keywords: SQLITE_CONFIG_COVERING_INDEX_SCAN SQLITE_CONFIG_GETMALLOC SQLITE_CONFIG_GETMUTEX SQLITE_CONFIG_GETPCACHE SQLITE_CONFIG_GETPCACHE2 SQLITE_CONFIG_HEAP SQLITE_CONFIG_LOG SQLITE_CONFIG_LOOKASIDE SQLITE_CONFIG_MALLOC SQLITE_CONFIG_MEMDB_MAXSIZE SQLITE_CONFIG_MEMSTATUS SQLITE_CONFIG_MMAP_SIZE SQLITE_CONFIG_MULTITHREAD SQLITE_CONFIG_MUTEX SQLITE_CONFIG_PAGECACHE SQLITE_CONFIG_PCACHE SQLITE_CONFIG_PCACHE2 SQLITE_CONFIG_PCACHE_HDRSZ SQLITE_CONFIG_PMASZ SQLITE_CONFIG_SCRATCH SQLITE_CONFIG_SERIALIZED SQLITE_CONFIG_SINGLETHREAD SQLITE_CONFIG_SMALL_MALLOC SQLITE_CONFIG_SORTERREF_SIZE SQLITE_CONFIG_SQLLOG SQLITE_CONFIG_STMTJRNL_SPILL SQLITE_CONFIG_URI SQLITE_CONFIG_WIN32_HEAPSIZE {configuration option} --> +<div class=nosearch> +<a href="../c3ref/intro.html"><h2>SQLite C Interface</h2></a> +<h2>Configuration Options</h2> +</div> +<blockquote><pre> +#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ +#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ +#define SQLITE_CONFIG_SERIALIZED 3 /* nil */ +#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ +#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ +#define SQLITE_CONFIG_SCRATCH 6 /* No longer used */ +#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ +#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ +#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ +#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ +#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ +/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ +#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ +#define SQLITE_CONFIG_PCACHE 14 /* no-op */ +#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ +#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ +#define SQLITE_CONFIG_URI 17 /* int */ +#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ +#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ +#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ +#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ +#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ +#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ +#define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ +#define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ +#define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ +#define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */ +#define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */ +#define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */ +</pre></blockquote> +<p> +These constants are the available integer configuration options that +can be passed as the first argument to the <a href="../c3ref/config.html">sqlite3_config()</a> interface.</p> + +<p>Most of the configuration options for sqlite3_config() +will only work if invoked prior to <a href="../c3ref/initialize.html">sqlite3_initialize()</a> or after +<a href="../c3ref/initialize.html">sqlite3_shutdown()</a>. The few exceptions to this rule are called +"anytime configuration options". +Calling <a href="../c3ref/config.html">sqlite3_config()</a> with a first argument that is not an +anytime configuration option in between calls to <a href="../c3ref/initialize.html">sqlite3_initialize()</a> and +<a href="../c3ref/initialize.html">sqlite3_shutdown()</a> is a no-op that returns SQLITE_MISUSE.</p> + +<p>The set of anytime configuration options can change (by insertions +and/or deletions) from one release of SQLite to the next. +As of SQLite version 3.42.0, the complete set of anytime configuration +options is: +<ul> +<li> SQLITE_CONFIG_LOG +<li> SQLITE_CONFIG_PCACHE_HDRSZ +</ul></p> + +<p>New configuration options may be added in future releases of SQLite. +Existing configuration options might be discontinued. Applications +should check the return code from <a href="../c3ref/config.html">sqlite3_config()</a> to make sure that +the call worked. The <a href="../c3ref/config.html">sqlite3_config()</a> interface will return a +non-zero <a href="../rescode.html">error code</a> if a discontinued or unsupported configuration option +is invoked.</p> + +<p><dl> +<a name="sqliteconfigsinglethread"></a> + <dt>SQLITE_CONFIG_SINGLETHREAD</dt> +<dd>There are no arguments to this option. This option sets the +<a href="../threadsafe.html">threading mode</a> to Single-thread. In other words, it disables +all mutexing and puts SQLite into a mode where it can only be used +by a single thread. If SQLite is compiled with +the <a href="../compile.html#threadsafe">SQLITE_THREADSAFE=0</a> compile-time option then +it is not possible to change the <a href="../threadsafe.html">threading mode</a> from its default +value of Single-thread and so <a href="../c3ref/config.html">sqlite3_config()</a> will return +<a href="../rescode.html#error">SQLITE_ERROR</a> if called with the SQLITE_CONFIG_SINGLETHREAD +configuration option.</dd></p> + +<p><a name="sqliteconfigmultithread"></a> + <dt>SQLITE_CONFIG_MULTITHREAD</dt> +<dd>There are no arguments to this option. This option sets the +<a href="../threadsafe.html">threading mode</a> to Multi-thread. In other words, it disables +mutexing on <a href="../c3ref/sqlite3.html">database connection</a> and <a href="../c3ref/stmt.html">prepared statement</a> objects. +The application is responsible for serializing access to +<a href="../c3ref/sqlite3.html">database connections</a> and <a href="../c3ref/stmt.html">prepared statements</a>. But other mutexes +are enabled so that SQLite will be safe to use in a multi-threaded +environment as long as no two threads attempt to use the same +<a href="../c3ref/sqlite3.html">database connection</a> at the same time. If SQLite is compiled with +the <a href="../compile.html#threadsafe">SQLITE_THREADSAFE=0</a> compile-time option then +it is not possible to set the Multi-thread <a href="../threadsafe.html">threading mode</a> and +<a href="../c3ref/config.html">sqlite3_config()</a> will return <a href="../rescode.html#error">SQLITE_ERROR</a> if called with the +SQLITE_CONFIG_MULTITHREAD configuration option.</dd></p> + +<p><a name="sqliteconfigserialized"></a> + <dt>SQLITE_CONFIG_SERIALIZED</dt> +<dd>There are no arguments to this option. This option sets the +<a href="../threadsafe.html">threading mode</a> to Serialized. In other words, this option enables +all mutexes including the recursive +mutexes on <a href="../c3ref/sqlite3.html">database connection</a> and <a href="../c3ref/stmt.html">prepared statement</a> objects. +In this mode (which is the default when SQLite is compiled with +<a href="../compile.html#threadsafe">SQLITE_THREADSAFE=1</a>) the SQLite library will itself serialize access +to <a href="../c3ref/sqlite3.html">database connections</a> and <a href="../c3ref/stmt.html">prepared statements</a> so that the +application is free to use the same <a href="../c3ref/sqlite3.html">database connection</a> or the +same <a href="../c3ref/stmt.html">prepared statement</a> in different threads at the same time. +If SQLite is compiled with +the <a href="../compile.html#threadsafe">SQLITE_THREADSAFE=0</a> compile-time option then +it is not possible to set the Serialized <a href="../threadsafe.html">threading mode</a> and +<a href="../c3ref/config.html">sqlite3_config()</a> will return <a href="../rescode.html#error">SQLITE_ERROR</a> if called with the +SQLITE_CONFIG_SERIALIZED configuration option.</dd></p> + +<p><a name="sqliteconfigmalloc"></a> + <dt>SQLITE_CONFIG_MALLOC</dt> +<dd> The SQLITE_CONFIG_MALLOC option takes a single argument which is +a pointer to an instance of the <a href="../c3ref/mem_methods.html">sqlite3_mem_methods</a> structure. +The argument specifies +alternative low-level memory allocation routines to be used in place of +the memory allocation routines built into SQLite. SQLite makes +its own private copy of the content of the <a href="../c3ref/mem_methods.html">sqlite3_mem_methods</a> structure +before the <a href="../c3ref/config.html">sqlite3_config()</a> call returns.</dd></p> + +<p><a name="sqliteconfiggetmalloc"></a> + <dt>SQLITE_CONFIG_GETMALLOC</dt> +<dd> The SQLITE_CONFIG_GETMALLOC option takes a single argument which +is a pointer to an instance of the <a href="../c3ref/mem_methods.html">sqlite3_mem_methods</a> structure. +The <a href="../c3ref/mem_methods.html">sqlite3_mem_methods</a> +structure is filled with the currently defined memory allocation routines. +This option can be used to overload the default memory allocation +routines with a wrapper that simulations memory allocation failure or +tracks memory usage, for example. </dd></p> + +<p><a name="sqliteconfigsmallmalloc"></a> + <dt>SQLITE_CONFIG_SMALL_MALLOC</dt> +<dd> The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of +type int, interpreted as a boolean, which if true provides a hint to +SQLite that it should avoid large memory allocations if possible. +SQLite will run faster if it is free to make large memory allocations, +but some application might prefer to run slower in exchange for +guarantees about memory fragmentation that are possible if large +allocations are avoided. This hint is normally off. +</dd></p> + +<p><a name="sqliteconfigmemstatus"></a> + <dt>SQLITE_CONFIG_MEMSTATUS</dt> +<dd> The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, +interpreted as a boolean, which enables or disables the collection of +memory allocation statistics. When memory allocation statistics are +disabled, the following SQLite interfaces become non-operational: +<ul> +<li> <a href="../c3ref/hard_heap_limit64.html">sqlite3_hard_heap_limit64()</a> +<li> <a href="../c3ref/memory_highwater.html">sqlite3_memory_used()</a> +<li> <a href="../c3ref/memory_highwater.html">sqlite3_memory_highwater()</a> +<li> <a href="../c3ref/hard_heap_limit64.html">sqlite3_soft_heap_limit64()</a> +<li> <a href="../c3ref/status.html">sqlite3_status64()</a> +</ul> +Memory allocation statistics are enabled by default unless SQLite is +compiled with <a href="../compile.html#default_memstatus">SQLITE_DEFAULT_MEMSTATUS</a>=0 in which case memory +allocation statistics are disabled by default. +</dd></p> + +<p><a name="sqliteconfigscratch"></a> + <dt>SQLITE_CONFIG_SCRATCH</dt> +<dd> The SQLITE_CONFIG_SCRATCH option is no longer used. +</dd></p> + +<p><a name="sqliteconfigpagecache"></a> + <dt>SQLITE_CONFIG_PAGECACHE</dt> +<dd> The SQLITE_CONFIG_PAGECACHE option specifies a memory pool +that SQLite can use for the database page cache with the default page +cache implementation. +This configuration option is a no-op if an application-defined page +cache implementation is loaded using the <a href="../c3ref/c_config_covering_index_scan.html#sqliteconfigpcache2">SQLITE_CONFIG_PCACHE2</a>. +There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to +8-byte aligned memory (pMem), the size of each page cache line (sz), +and the number of cache lines (N). +The sz argument should be the size of the largest database page +(a power of two between 512 and 65536) plus some extra bytes for each +page header. The number of extra bytes needed by the page header +can be determined using <a href="../c3ref/c_config_covering_index_scan.html#sqliteconfigpcachehdrsz">SQLITE_CONFIG_PCACHE_HDRSZ</a>. +It is harmless, apart from the wasted memory, +for the sz parameter to be larger than necessary. The pMem +argument must be either a NULL pointer or a pointer to an 8-byte +aligned block of memory of at least sz*N bytes, otherwise +subsequent behavior is undefined. +When pMem is not NULL, SQLite will strive to use the memory provided +to satisfy page cache needs, falling back to <a href="../c3ref/free.html">sqlite3_malloc()</a> if +a page cache line is larger than sz bytes or if all of the pMem buffer +is exhausted. +If pMem is NULL and N is non-zero, then each database connection +does an initial bulk allocation for page cache memory +from <a href="../c3ref/free.html">sqlite3_malloc()</a> sufficient for N cache lines if N is positive or +of -1024*N bytes if N is negative, . If additional +page cache memory is needed beyond what is provided by the initial +allocation, then SQLite goes to <a href="../c3ref/free.html">sqlite3_malloc()</a> separately for each +additional cache line. </dd></p> + +<p><a name="sqliteconfigheap"></a> + <dt>SQLITE_CONFIG_HEAP</dt> +<dd> The SQLITE_CONFIG_HEAP option specifies a static memory buffer +that SQLite will use for all of its dynamic memory allocation needs +beyond those provided for by <a href="../c3ref/c_config_covering_index_scan.html#sqliteconfigpagecache">SQLITE_CONFIG_PAGECACHE</a>. +The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled +with either <a href="../compile.html#enable_memsys3">SQLITE_ENABLE_MEMSYS3</a> or <a href="../compile.html#enable_memsys5">SQLITE_ENABLE_MEMSYS5</a> and returns +<a href="../rescode.html#error">SQLITE_ERROR</a> if invoked otherwise. +There are three arguments to SQLITE_CONFIG_HEAP: +An 8-byte aligned pointer to the memory, +the number of bytes in the memory buffer, and the minimum allocation size. +If the first pointer (the memory pointer) is NULL, then SQLite reverts +to using its default memory allocator (the system malloc() implementation), +undoing any prior invocation of <a href="../c3ref/c_config_covering_index_scan.html#sqliteconfigmalloc">SQLITE_CONFIG_MALLOC</a>. If the +memory pointer is not NULL then the alternative memory +allocator is engaged to handle all of SQLites memory allocation needs. +The first pointer (the memory pointer) must be aligned to an 8-byte +boundary or subsequent behavior of SQLite will be undefined. +The minimum allocation size is capped at 2**12. Reasonable values +for the minimum allocation size are 2**5 through 2**8.</dd></p> + +<p><a name="sqliteconfigmutex"></a> + <dt>SQLITE_CONFIG_MUTEX</dt> +<dd> The SQLITE_CONFIG_MUTEX option takes a single argument which is a +pointer to an instance of the <a href="../c3ref/mutex_methods.html">sqlite3_mutex_methods</a> structure. +The argument specifies alternative low-level mutex routines to be used +in place the mutex routines built into SQLite. SQLite makes a copy of +the content of the <a href="../c3ref/mutex_methods.html">sqlite3_mutex_methods</a> structure before the call to +<a href="../c3ref/config.html">sqlite3_config()</a> returns. If SQLite is compiled with +the <a href="../compile.html#threadsafe">SQLITE_THREADSAFE=0</a> compile-time option then +the entire mutexing subsystem is omitted from the build and hence calls to +<a href="../c3ref/config.html">sqlite3_config()</a> with the SQLITE_CONFIG_MUTEX configuration option will +return <a href="../rescode.html#error">SQLITE_ERROR</a>.</dd></p> + +<p><a name="sqliteconfiggetmutex"></a> + <dt>SQLITE_CONFIG_GETMUTEX</dt> +<dd> The SQLITE_CONFIG_GETMUTEX option takes a single argument which +is a pointer to an instance of the <a href="../c3ref/mutex_methods.html">sqlite3_mutex_methods</a> structure. The +<a href="../c3ref/mutex_methods.html">sqlite3_mutex_methods</a> +structure is filled with the currently defined mutex routines. +This option can be used to overload the default mutex allocation +routines with a wrapper used to track mutex usage for performance +profiling or testing, for example. If SQLite is compiled with +the <a href="../compile.html#threadsafe">SQLITE_THREADSAFE=0</a> compile-time option then +the entire mutexing subsystem is omitted from the build and hence calls to +<a href="../c3ref/config.html">sqlite3_config()</a> with the SQLITE_CONFIG_GETMUTEX configuration option will +return <a href="../rescode.html#error">SQLITE_ERROR</a>.</dd></p> + +<p><a name="sqliteconfiglookaside"></a> + <dt>SQLITE_CONFIG_LOOKASIDE</dt> +<dd> The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine +the default size of lookaside memory on each <a href="../c3ref/sqlite3.html">database connection</a>. +The first argument is the +size of each lookaside buffer slot and the second is the number of +slots allocated to each database connection. SQLITE_CONFIG_LOOKASIDE +sets the <i>default</i> lookaside size. The <a href="../c3ref/c_dbconfig_defensive.html#sqlitedbconfiglookaside">SQLITE_DBCONFIG_LOOKASIDE</a> +option to <a href="../c3ref/db_config.html">sqlite3_db_config()</a> can be used to change the lookaside +configuration on individual connections. </dd></p> + +<p><a name="sqliteconfigpcache2"></a> + <dt>SQLITE_CONFIG_PCACHE2</dt> +<dd> The SQLITE_CONFIG_PCACHE2 option takes a single argument which is +a pointer to an <a href="../c3ref/pcache_methods2.html">sqlite3_pcache_methods2</a> object. This object specifies +the interface to a custom page cache implementation. +SQLite makes a copy of the <a href="../c3ref/pcache_methods2.html">sqlite3_pcache_methods2</a> object.</dd></p> + +<p><a name="sqliteconfiggetpcache2"></a> + <dt>SQLITE_CONFIG_GETPCACHE2</dt> +<dd> The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which +is a pointer to an <a href="../c3ref/pcache_methods2.html">sqlite3_pcache_methods2</a> object. SQLite copies of +the current page cache implementation into that object. </dd></p> + +<p><a name="sqliteconfiglog"></a> + <dt>SQLITE_CONFIG_LOG</dt> +<dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite +global <a href="../errlog.html">error log</a>. +(The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a +function with a call signature of void(*)(void*,int,const char*), +and a pointer to void. If the function pointer is not NULL, it is +invoked by <a href="../c3ref/log.html">sqlite3_log()</a> to process each logging event. If the +function pointer is NULL, the <a href="../c3ref/log.html">sqlite3_log()</a> interface becomes a no-op. +The void pointer that is the second argument to SQLITE_CONFIG_LOG is +passed through as the first parameter to the application-defined logger +function whenever that function is invoked. The second parameter to +the logger function is a copy of the first parameter to the corresponding +<a href="../c3ref/log.html">sqlite3_log()</a> call and is intended to be a <a href="../rescode.html">result code</a> or an +<a href="../rescode.html#extrc">extended result code</a>. The third parameter passed to the logger is +log message after formatting via <a href="../c3ref/mprintf.html">sqlite3_snprintf()</a>. +The SQLite logging interface is not reentrant; the logger function +supplied by the application must not invoke any SQLite interface. +In a multi-threaded application, the application-defined logger +function must be threadsafe. </dd></p> + +<p><a name="sqliteconfiguri"></a> + <dt>SQLITE_CONFIG_URI +<dd>The SQLITE_CONFIG_URI option takes a single argument of type int. +If non-zero, then URI handling is globally enabled. If the parameter is zero, +then URI handling is globally disabled. If URI handling is globally +enabled, all filenames passed to <a href="../c3ref/open.html">sqlite3_open()</a>, <a href="../c3ref/open.html">sqlite3_open_v2()</a>, +<a href="../c3ref/open.html">sqlite3_open16()</a> or +specified as part of <a href="../lang_attach.html">ATTACH</a> commands are interpreted as URIs, regardless +of whether or not the <a href="../c3ref/c_open_autoproxy.html">SQLITE_OPEN_URI</a> flag is set when the database +connection is opened. If it is globally disabled, filenames are +only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the +database connection is opened. By default, URI handling is globally +disabled. The default value may be changed by compiling with the +<a href="../compile.html#use_uri">SQLITE_USE_URI</a> symbol defined.</p> + +<p><a name="sqliteconfigcoveringindexscan"></a> + <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN +<dd>The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer +argument which is interpreted as a boolean in order to enable or disable +the use of covering indices for full table scans in the query optimizer. +The default setting is determined +by the <a href="../compile.html#allow_covering_index_scan">SQLITE_ALLOW_COVERING_INDEX_SCAN</a> compile-time option, or is "on" +if that compile-time option is omitted. +The ability to disable the use of covering indices for full table scans +is because some incorrectly coded legacy applications might malfunction +when the optimization is enabled. Providing the ability to +disable the optimization allows the older, buggy application code to work +without change even with newer versions of SQLite.</p> + +<p><a name="sqliteconfigpcache"></a> + <a name="sqliteconfiggetpcache"></a> + +<dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE +<dd> These options are obsolete and should not be used by new code. +They are retained for backwards compatibility but are now no-ops. +</dd></p> + +<p><a name="sqliteconfigsqllog"></a> + +<dt>SQLITE_CONFIG_SQLLOG +<dd>This option is only available if sqlite is compiled with the +<a href="../compile.html#enable_sqllog">SQLITE_ENABLE_SQLLOG</a> pre-processor macro defined. The first argument should +be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). +The second should be of type (void*). The callback is invoked by the library +in three separate circumstances, identified by the value passed as the +fourth parameter. If the fourth parameter is 0, then the database connection +passed as the second argument has just been opened. The third argument +points to a buffer containing the name of the main database file. If the +fourth parameter is 1, then the SQL statement that the third parameter +points to has just been executed. Or, if the fourth parameter is 2, then +the connection being passed as the second parameter is being closed. The +third parameter is passed NULL In this case. An example of using this +configuration option can be seen in the "test_sqllog.c" source file in +the canonical SQLite source tree.</dd></p> + +<p><a name="sqliteconfigmmapsize"></a> + +<dt>SQLITE_CONFIG_MMAP_SIZE +<dd>SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values +that are the default mmap size limit (the default setting for +<a href="../pragma.html#pragma_mmap_size">PRAGMA mmap_size</a>) and the maximum allowed mmap size limit. +The default setting can be overridden by each database connection using +either the <a href="../pragma.html#pragma_mmap_size">PRAGMA mmap_size</a> command, or by using the +<a href="../c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlmmapsize">SQLITE_FCNTL_MMAP_SIZE</a> file control. The maximum allowed mmap size +will be silently truncated if necessary so that it does not exceed the +compile-time maximum mmap size set by the +<a href="../compile.html#max_mmap_size">SQLITE_MAX_MMAP_SIZE</a> compile-time option. +If either argument to this option is negative, then that argument is +changed to its compile-time default.</p> + +<p><a name="sqliteconfigwin32heapsize"></a> + +<dt>SQLITE_CONFIG_WIN32_HEAPSIZE +<dd>The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is +compiled for Windows with the <a href="../compile.html#win32_malloc">SQLITE_WIN32_MALLOC</a> pre-processor macro +defined. SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value +that specifies the maximum size of the created heap.</p> + +<p><a name="sqliteconfigpcachehdrsz"></a> + +<dt>SQLITE_CONFIG_PCACHE_HDRSZ +<dd>The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which +is a pointer to an integer and writes into that integer the number of extra +bytes per page required for each page in <a href="../c3ref/c_config_covering_index_scan.html#sqliteconfigpagecache">SQLITE_CONFIG_PAGECACHE</a>. +The amount of extra space required can change depending on the compiler, +target platform, and SQLite version.</p> + +<p><a name="sqliteconfigpmasz"></a> + +<dt>SQLITE_CONFIG_PMASZ +<dd>The SQLITE_CONFIG_PMASZ option takes a single parameter which +is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded +sorter to that integer. The default minimum PMA Size is set by the +<a href="../compile.html#sorter_pmasz">SQLITE_SORTER_PMASZ</a> compile-time option. New threads are launched +to help with sort operations when multithreaded sorting +is enabled (using the <a href="../pragma.html#pragma_threads">PRAGMA threads</a> command) and the amount of content +to be sorted exceeds the page size times the minimum of the +<a href="../pragma.html#pragma_cache_size">PRAGMA cache_size</a> setting and this value.</p> + +<p><a name="sqliteconfigstmtjrnlspill"></a> + +<dt>SQLITE_CONFIG_STMTJRNL_SPILL +<dd>The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which +becomes the <a href="../tempfiles.html#stmtjrnl">statement journal</a> spill-to-disk threshold. +<a href="../tempfiles.html#stmtjrnl">Statement journals</a> are held in memory until their size (in bytes) +exceeds this threshold, at which point they are written to disk. +Or if the threshold is -1, statement journals are always held +exclusively in memory. +Since many statement journals never become large, setting the spill +threshold to a value such as 64KiB can greatly reduce the amount of +I/O required to support statement rollback. +The default value for this setting is controlled by the +<a href="../compile.html#stmtjrnl_spill">SQLITE_STMTJRNL_SPILL</a> compile-time option.</p> + +<p><a name="sqliteconfigsorterrefsize"></a> + +<dt>SQLITE_CONFIG_SORTERREF_SIZE +<dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter +of type (int) - the new value of the sorter-reference size threshold. +Usually, when SQLite uses an external sort to order records according +to an ORDER BY clause, all fields required by the caller are present in the +sorted records. However, if SQLite determines based on the declared type +of a table column that its values are likely to be very large - larger +than the configured sorter-reference size threshold - then a reference +is stored in each sorted record and the required column values loaded +from the database as records are returned in sorted order. The default +value for this option is to never use this optimization. Specifying a +negative value for this option restores the default behavior. +This option is only available if SQLite is compiled with the +<a href="../compile.html#enable_sorter_references">SQLITE_ENABLE_SORTER_REFERENCES</a> compile-time option.</p> + +<p><a name="sqliteconfigmemdbmaxsize"></a> + +<dt>SQLITE_CONFIG_MEMDB_MAXSIZE +<dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter +<a href="../c3ref/int64.html">sqlite3_int64</a> parameter which is the default maximum size for an in-memory +database created using <a href="../c3ref/deserialize.html">sqlite3_deserialize()</a>. This default maximum +size can be adjusted up or down for individual databases using the +<a href="../c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlsizelimit">SQLITE_FCNTL_SIZE_LIMIT</a> <a href="../c3ref/file_control.html">file-control</a>. If this +configuration setting is never used, then the default maximum is determined +by the <a href="../compile.html#memdb_default_maxsize">SQLITE_MEMDB_DEFAULT_MAXSIZE</a> compile-time option. If that +compile-time option is not set, then the default maximum is 1073741824. +</dl> +</p><p>See also lists of + <a href="../c3ref/objlist.html">Objects</a>, + <a href="../c3ref/constlist.html">Constants</a>, and + <a href="../c3ref/funclist.html">Functions</a>.</p> + |