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<h2 class="title" style="clear: both"><a id="dbset_heapsize"></a>Db::set_heapsize()</h2>
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<pre class="programlisting">#include <db_cxx.h>
int
Db::set_heapsize(u_int32_t gbytes, u_int32_t bytes, u_int32_t flags);</pre>
<p>
Sets the maximum on-disk database file size used by a database
configured to use the Heap access method. If this method is never
called, the database's file size can grow without bound. If this
method is called, then the heap file can never grow larger than the
limit defined by this method. In that case, attempts to update or
create records in a Heap database that has reached its maximum size
will result in a <code class="literal">DB_HEAP_FULL</code> error return.
</p>
<p>
The size specified to this method must be at least three times the
database page size. That is, a Heap database must contain at least
three database pages. You can set the database page size using the
<a class="xref" href="dbset_pagesize.html" title="Db::set_pagesize()">Db::set_pagesize()</a>
method.
</p>
<p>
The <code class="methodname">Db::set_heapsize()</code> method may not be
called after the <a class="xref" href="dbopen.html" title="Db::open()">Db::open()</a>
method is called. Further, if this method is called on an existing
Heap database, the size specified here must match the size used to
create the database. Note, however, that specifying an incorrect
size to this method will not result in an error return
(<code class="literal">EINVAL</code>) until the database is opened.
</p>
<p>
The <code class="methodname">Db::set_heapsize()</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>
</span>
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<div class="sect2" lang="en" xml:lang="en">
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<h3 class="title"><a id="idp304328"></a>Parameters</h3>
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<h4 class="title"><a id="idp304176"></a>gbytes</h4>
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<p>
The size of the heap is set to <span class="bold"><strong>gbytes</strong></span> gigabytes plus <span class="bold"><strong>bytes</strong></span>.
</p>
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<div class="sect3" lang="en" xml:lang="en">
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<h4 class="title"><a id="idp277496"></a>bytes</h4>
</div>
</div>
</div>
<p>
The size of the heap is set to <span class="bold"><strong>gbytes</strong></span> gigabytes plus <span class="bold"><strong>bytes</strong></span>.
</p>
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<div class="sect3" lang="en" xml:lang="en">
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<h4 class="title"><a id="idp289728"></a>flags</h4>
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<p>
The <span class="bold"><strong>flags</strong></span> parameter is currently
unused, and must be set to 0.
</p>
</div>
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<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
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<h3 class="title"><a id="idp276840"></a>Errors</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">Db::set_heapsize()</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>
</span>
</p>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
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<h4 class="title"><a id="idp312272"></a>EINVAL</h4>
</div>
</div>
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<p>
If the specified heap size was too small; 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.
</p>
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<div class="sect2" lang="en" xml:lang="en">
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<h3 class="title"><a id="idp309216"></a>Class</h3>
</div>
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<a class="link" href="db.html" title="Chapter 2. The Db Handle">Db</a>
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<div class="sect2" lang="en" xml:lang="en">
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<h3 class="title"><a id="idp306280"></a>See Also</h3>
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<a class="xref" href="db.html#dblist" title="Database and Related Methods">Database and Related Methods</a>
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