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diff --git a/www/c3ref/update_hook.html b/www/c3ref/update_hook.html new file mode 100644 index 0000000..afed2fa --- /dev/null +++ b/www/c3ref/update_hook.html @@ -0,0 +1,179 @@ +<!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>Data Change Notification Callbacks</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_update_hook --> +<div class=nosearch> +<a href="intro.html"><h2>SQLite C Interface</h2></a> +<h2>Data Change Notification Callbacks</h2> +</div> +<blockquote><pre> +void *sqlite3_update_hook( + sqlite3*, + void(*)(void *,int ,char const *,char const *,sqlite3_int64), + void* +); +</pre></blockquote> +<p> +The sqlite3_update_hook() interface registers a callback function +with the <a href="../c3ref/sqlite3.html">database connection</a> identified by the first argument +to be invoked whenever a row is updated, inserted or deleted in +a <a href="../rowidtable.html">rowid table</a>. +Any callback set by a previous call to this function +for the same database connection is overridden.</p> + +<p>The second argument is a pointer to the function to invoke when a +row is updated, inserted or deleted in a rowid table. +The first argument to the callback is a copy of the third argument +to sqlite3_update_hook(). +The second callback argument is one of <a href="../c3ref/c_alter_table.html">SQLITE_INSERT</a>, <a href="../c3ref/c_alter_table.html">SQLITE_DELETE</a>, +or <a href="../c3ref/c_alter_table.html">SQLITE_UPDATE</a>, depending on the operation that caused the callback +to be invoked. +The third and fourth arguments to the callback contain pointers to the +database and table name containing the affected row. +The final callback parameter is the <a href="../lang_createtable.html#rowid">rowid</a> of the row. +In the case of an update, this is the <a href="../lang_createtable.html#rowid">rowid</a> after the update takes place.</p> + +<p>The update hook is not invoked when internal system tables are +modified (i.e. sqlite_sequence). +The update hook is not invoked when <a href="../withoutrowid.html">WITHOUT ROWID</a> tables are modified.</p> + +<p>In the current implementation, the update hook +is not invoked when conflicting rows are deleted because of an +<a href="../lang_conflict.html">ON CONFLICT REPLACE</a> clause. Nor is the update hook +invoked when rows are deleted using the <a href="../lang_delete.html#truncateopt">truncate optimization</a>. +The exceptions defined in this paragraph might change in a future +release of SQLite.</p> + +<p>The update hook implementation must not do anything that will modify +the database connection that invoked the update hook. Any actions +to modify the database connection must be deferred until after the +completion of the <a href="../c3ref/step.html">sqlite3_step()</a> call that triggered the update hook. +Note that <a href="../c3ref/prepare.html">sqlite3_prepare_v2()</a> and <a href="../c3ref/step.html">sqlite3_step()</a> both modify their +database connections for the meaning of "modify" in this paragraph.</p> + +<p>The sqlite3_update_hook(D,C,P) function +returns the P argument from the previous call +on the same <a href="../c3ref/sqlite3.html">database connection</a> D, or NULL for +the first call on D.</p> + +<p>See also the <a href="../c3ref/commit_hook.html">sqlite3_commit_hook()</a>, <a href="../c3ref/commit_hook.html">sqlite3_rollback_hook()</a>, +and <a href="../c3ref/preupdate_blobwrite.html">sqlite3_preupdate_hook()</a> interfaces. +</p><p>See also lists of + <a href="objlist.html">Objects</a>, + <a href="constlist.html">Constants</a>, and + <a href="funclist.html">Functions</a>.</p> + |