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<a href="intro.html"><h2>SQLite C Interface</h2></a>
<h2>Recover snapshots from a wal file</h2>
</div>
<blockquote><pre>
int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb);
</pre></blockquote>
<p>
If a <a href="../wal.html#walfile">WAL file</a> remains on disk after all database connections close
(either through the use of the <a href="../c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlpersistwal">SQLITE_FCNTL_PERSIST_WAL</a> <a href="../c3ref/file_control.html">file control</a>
or because the last process to have the database opened exited without
calling <a href="../c3ref/close.html">sqlite3_close()</a>) and a new connection is subsequently opened
on that database and <a href="../wal.html#walfile">WAL file</a>, the <a href="../c3ref/snapshot_open.html">sqlite3_snapshot_open()</a> interface
will only be able to open the last transaction added to the WAL file
even though the WAL file contains other valid transactions.</p>

<p>This function attempts to scan the WAL file associated with database zDb
of database handle db and make all valid snapshots available to
sqlite3_snapshot_open(). It is an error if there is already a read
transaction open on the database, or if the database is not a WAL mode
database.</p>

<p>SQLITE_OK is returned if successful, or an SQLite error code otherwise.</p>

<p>This interface is only available if SQLite is compiled with the
<a href="../compile.html#enable_snapshot">SQLITE_ENABLE_SNAPSHOT</a> option.
</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>