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<div class=nosearch>
<a href="../c3ref/intro.html"><h2>SQLite C Interface</h2></a>
<h2>Configure an auto-checkpoint</h2>
</div>
<blockquote><pre>
int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
</pre></blockquote>
<p>
The <a href="../c3ref/wal_autocheckpoint.html">sqlite3_wal_autocheckpoint(D,N)</a> is a wrapper around
<a href="../c3ref/wal_hook.html">sqlite3_wal_hook()</a> that causes any database on <a href="../c3ref/sqlite3.html">database connection</a> D
to automatically <a href="../wal.html#ckpt">checkpoint</a>
after committing a transaction if there are N or
more frames in the <a href="../wal.html">write-ahead log</a> file.  Passing zero or
a negative value as the nFrame parameter disables automatic
checkpoints entirely.</p>

<p>The callback registered by this function replaces any existing callback
registered using <a href="../c3ref/wal_hook.html">sqlite3_wal_hook()</a>.  Likewise, registering a callback
using <a href="../c3ref/wal_hook.html">sqlite3_wal_hook()</a> disables the automatic checkpoint mechanism
configured by this function.</p>

<p>The <a href="../pragma.html#pragma_wal_autocheckpoint">wal_autocheckpoint pragma</a> can be used to invoke this interface
from SQL.</p>

<p>Checkpoints initiated by this mechanism are
<a href="../c3ref/wal_checkpoint_v2.html">PASSIVE</a>.</p>

<p>Every new <a href="../c3ref/sqlite3.html">database connection</a> defaults to having the auto-checkpoint
enabled with a threshold of 1000 or <a href="../compile.html#default_wal_autocheckpoint">SQLITE_DEFAULT_WAL_AUTOCHECKPOINT</a>
pages.  The use of this interface
is only necessary if the default setting is found to be suboptimal
for a particular application.
</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>