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<h2 class="title" style="clear: both"><a id="dbset_q_extentsize"></a>Db::set_q_extentsize()</h2>
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<pre class="programlisting">#include &lt;db_cxx.h&gt;
int
Db::set_q_extentsize(u_int32_t extentsize); </pre>
<p>
Set the size of the extents used to hold pages in a Queue database,
specified as a number of pages. Each extent is created as a separate
physical file. If no extent size is set, the default behavior is to
create only a single underlying database file.
</p>
<p>
For information on tuning the extent size, see <a href="../../programmer_reference/rq_conf.html#am_conf_extentsize" class="olink">Selecting a extent size</a>.
</p>
<p>
The <code class="methodname">Db::set_q_extentsize()</code> method configures a database, not only
operations performed using the specified <a class="link" href="db.html" title="Chapter 2.  The Db Handle">Db</a>
handle.
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<p>
The <code class="methodname">Db::set_q_extentsize()</code> method may not be called after the
<a class="xref" href="dbopen.html" title="Db::open()">Db::open()</a> method is called. If
the database already exists when
<a class="xref" href="dbopen.html" title="Db::open()">Db::open()</a> is called, the
information specified to <code class="methodname">Db::set_q_extentsize()</code> will be ignored.
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<p>
The <code class="methodname">Db::set_q_extentsize()</code> <span>
<span>
method either returns a non-zero error value or throws an
exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</span>
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<h3 class="title"><a id="id3599195"></a>Parameters</h3>
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<h4 class="title"><a id="id3599380"></a>extentsize</h4>
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<p>
The <span class="bold"><strong>extentsize</strong></span> parameter is the
number of pages in a Queue database extent.
</p>
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<h3 class="title"><a id="id3599210"></a>Errors</h3>
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<p>
The <code class="methodname">Db::set_q_extentsize()</code> <span>
<span>
method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a>
exception, encapsulating one of the following non-zero errors, or return one
of the following non-zero errors:
</span>
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<h4 class="title"><a id="id3599457"></a>EINVAL</h4>
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<p>
If the method was called after <a class="xref" href="dbopen.html" title="Db::open()">Db::open()</a>
was called; or if an invalid flag value or parameter was specified.
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<a class="link" href="db.html" title="Chapter 2.  The Db Handle">Db</a>
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<h3 class="title"><a id="id3599241"></a>See Also</h3>
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