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diff --git a/www/c3ref/snapshot_get.html b/www/c3ref/snapshot_get.html new file mode 100644 index 0000000..35b73c0 --- /dev/null +++ b/www/c3ref/snapshot_get.html @@ -0,0 +1,173 @@ +<!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>Record A Database Snapshot</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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On success, the +<a href="../c3ref/snapshot_get.html">sqlite3_snapshot_get(D,S,P)</a> interface writes a pointer to the newly +created <a href="../c3ref/snapshot.html">sqlite3_snapshot</a> object into *P and returns SQLITE_OK. +If there is not already a read-transaction open on schema S when +this function is called, one is opened automatically.</p> + +<p>The following must be true for this function to succeed. If any of +the following statements are false when sqlite3_snapshot_get() is +called, SQLITE_ERROR is returned. The final value of *P is undefined +in this case.</p> + +<p><ul> +<li> The database handle must not be in <a href="../c3ref/get_autocommit.html">autocommit mode</a>.</p> + +<p><li> Schema S of <a href="../c3ref/sqlite3.html">database connection</a> D must be a <a href="../wal.html">WAL mode</a> database.</p> + +<p><li> There must not be a write transaction open on schema S of database +connection D.</p> + +<p><li> One or more transactions must have been written to the current wal +file since it was created on disk (by any connection). This means +that a snapshot cannot be taken on a wal mode database with no wal +file immediately after it is first opened. At least one transaction +must be written to it first. +</ul></p> + +<p>This function may also return SQLITE_NOMEM. If it is called with the +database handle in autocommit mode but fails for some other reason, +whether or not a read transaction is opened on schema S is undefined.</p> + +<p>The <a href="../c3ref/snapshot.html">sqlite3_snapshot</a> object returned from a successful call to +<a href="../c3ref/snapshot_get.html">sqlite3_snapshot_get()</a> must be freed using <a href="../c3ref/snapshot_free.html">sqlite3_snapshot_free()</a> +to avoid a memory leak.</p> + +<p>The <a href="../c3ref/snapshot_get.html">sqlite3_snapshot_get()</a> interface is only available when the +<a href="../compile.html#enable_snapshot">SQLITE_ENABLE_SNAPSHOT</a> compile-time option is used. +</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> + |