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diff --git a/www/c3ref/wal_hook.html b/www/c3ref/wal_hook.html new file mode 100644 index 0000000..44c3827 --- /dev/null +++ b/www/c3ref/wal_hook.html @@ -0,0 +1,165 @@ +<!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>Write-Ahead Log Commit Hook</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. 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The second is a copy of the database handle. +The third parameter is the name of the database that was written to - +either "main" or the name of an <a href="../lang_attach.html">ATTACH</a>-ed database. The fourth parameter +is the number of pages currently in the write-ahead log file, +including those that were just committed.</p> + +<p>The callback function should normally return <a href="../rescode.html#ok">SQLITE_OK</a>. If an error +code is returned, that error will propagate back up through the +SQLite code base to cause the statement that provoked the callback +to report an error, though the commit will have still occurred. If the +callback returns <a href="../rescode.html#row">SQLITE_ROW</a> or <a href="../rescode.html#done">SQLITE_DONE</a>, or if it returns a value +that does not correspond to any valid SQLite error code, the results +are undefined.</p> + +<p>A single database handle may have at most a single write-ahead log callback +registered at one time. Calling <a href="../c3ref/wal_hook.html">sqlite3_wal_hook()</a> replaces any +previously registered write-ahead log callback. The return value is +a copy of the third parameter from the previous call, if any, or 0. +Note that the <a href="../c3ref/wal_autocheckpoint.html">sqlite3_wal_autocheckpoint()</a> interface and the +<a href="../pragma.html#pragma_wal_autocheckpoint">wal_autocheckpoint pragma</a> both invoke <a href="../c3ref/wal_hook.html">sqlite3_wal_hook()</a> and will +overwrite any prior <a href="../c3ref/wal_hook.html">sqlite3_wal_hook()</a> settings. +</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> + |