<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>Db::set_heapsize()</title> <link rel="stylesheet" href="apiReference.css" type="text/css" /> <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> <link rel="start" href="index.html" title="Berkeley DB C++ API Reference" /> <link rel="up" href="db.html" title="Chapter 2. The Db Handle" /> <link rel="prev" href="dbset_h_nelem.html" title="Db::set_h_nelem()" /> <link rel="next" href="dbset_heap_regionsize.html" title="Db::set_heap_regionsize()" /> </head> <body> <div xmlns="" class="navheader"> <div class="libver"> <p>Library Version 11.2.5.3</p> </div> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">Db::set_heapsize()</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="dbset_h_nelem.html">Prev</a> </td> <th width="60%" align="center">Chapter 2. The Db Handle </th> <td width="20%" align="right"> <a accesskey="n" href="dbset_heap_regionsize.html">Next</a></td> </tr> </table> <hr /> </div> <div class="sect1" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h2 class="title" style="clear: both"><a id="dbset_heapsize"></a>Db::set_heapsize()</h2> </div> </div> </div> <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> </p> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="idp5652792"></a>Parameters</h3> </div> </div> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="idp5652640"></a>gbytes</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> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="idp5640896"></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> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="idp5651648"></a>flags</h4> </div> </div> </div> <p> The <span class="bold"><strong>flags</strong></span> parameter is currently unused, and must be set to 0. </p> </div> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="idp5626184"></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"> <div> <div> <h4 class="title"><a id="idp5660904"></a>EINVAL</h4> </div> </div> </div> <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> </div> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="idp5663024"></a>Class</h3> </div> </div> </div> <p> <a class="link" href="db.html" title="Chapter 2. The Db Handle">Db</a> </p> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="idp5653488"></a>See Also</h3> </div> </div> </div> <p> <a class="xref" href="db.html#dblist" title="Database and Related Methods">Database and Related Methods</a> </p> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="dbset_h_nelem.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="db.html">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="dbset_heap_regionsize.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">Db::set_h_nelem() </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> Db::set_heap_regionsize()</td> </tr> </table> </div> </body> </html>