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diff --git a/www/c3ref/stmt_scanstatus.html b/www/c3ref/stmt_scanstatus.html new file mode 100644 index 0000000..e5f3456 --- /dev/null +++ b/www/c3ref/stmt_scanstatus.html @@ -0,0 +1,175 @@ +<!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>Prepared Statement Scan Status</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: sqlite3_stmt_scanstatus sqlite3_stmt_scanstatus_v2 --> +<div class=nosearch> +<a href="../c3ref/intro.html"><h2>SQLite C Interface</h2></a> +<h2>Prepared Statement Scan Status</h2> +</div> +<blockquote><pre> +int sqlite3_stmt_scanstatus( + sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ + int idx, /* Index of loop to report on */ + int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ + void *pOut /* Result written here */ +); +int sqlite3_stmt_scanstatus_v2( + sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ + int idx, /* Index of loop to report on */ + int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ + int flags, /* Mask of flags defined below */ + void *pOut /* Result written here */ +); +</pre></blockquote> +<p> +These interfaces return information about the predicted and measured +performance for pStmt. Advanced applications can use this +interface to compare the predicted and the measured performance and +issue warnings and/or rerun <a href="../lang_analyze.html">ANALYZE</a> if discrepancies are found.</p> + +<p>Since this interface is expected to be rarely used, it is only +available if SQLite is compiled using the <a href="../compile.html#enable_stmt_scanstatus">SQLITE_ENABLE_STMT_SCANSTATUS</a> +compile-time option.</p> + +<p>The "iScanStatusOp" parameter determines which status information to return. +The "iScanStatusOp" must be one of the <a href="../c3ref/c_scanstat_est.html">scanstatus options</a> or the behavior +of this interface is undefined. The requested measurement is written into +a variable pointed to by the "pOut" parameter.</p> + +<p>The "flags" parameter must be passed a mask of flags. At present only +one flag is defined - SQLITE_SCANSTAT_COMPLEX. If SQLITE_SCANSTAT_COMPLEX +is specified, then status information is available for all elements +of a query plan that are reported by "EXPLAIN QUERY PLAN" output. If +SQLITE_SCANSTAT_COMPLEX is not specified, then only query plan elements +that correspond to query loops (the "SCAN..." and "SEARCH..." elements of +the EXPLAIN QUERY PLAN output) are available. Invoking API +sqlite3_stmt_scanstatus() is equivalent to calling +sqlite3_stmt_scanstatus_v2() with a zeroed flags parameter.</p> + +<p>Parameter "idx" identifies the specific query element to retrieve statistics +for. Query elements are numbered starting from zero. A value of -1 may be +to query for statistics regarding the entire query. If idx is out of range +- less than -1 or greater than or equal to the total number of query +elements used to implement the statement - a non-zero value is returned and +the variable that pOut points to is unchanged.</p> + +<p>See also: <a href="../c3ref/stmt_scanstatus_reset.html">sqlite3_stmt_scanstatus_reset()</a> +</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> + |