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199 lines
7.1 KiB
HTML
199 lines
7.1 KiB
HTML
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<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml">
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
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<title>DBcursor->count()</title>
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<link rel="stylesheet" href="apiReference.css" type="text/css" />
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<meta name="generator" content="DocBook XSL Stylesheets V1.73.2" />
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<link rel="start" href="index.html" title="Berkeley DB C API Reference" />
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<link rel="up" href="dbc.html" title="Chapter 3. The DBcursor Handle" />
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<link rel="prev" href="dbccmp.html" title="DBcursor->cmp()" />
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<link rel="next" href="dbcdel.html" title="DBcursor->del()" />
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</head>
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<body>
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<div xmlns="" class="navheader">
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<div class="libver">
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<p>Library Version 11.2.5.2</p>
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</div>
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<table width="100%" summary="Navigation header">
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<tr>
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<th colspan="3" align="center">DBcursor->count()</th>
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</tr>
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<tr>
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<td width="20%" align="left"><a accesskey="p" href="dbccmp.html">Prev</a> </td>
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<th width="60%" align="center">Chapter 3.
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The DBcursor Handle
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</th>
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<td width="20%" align="right"> <a accesskey="n" href="dbcdel.html">Next</a></td>
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</tr>
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</table>
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<hr />
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</div>
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<div class="sect1" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h2 class="title" style="clear: both"><a id="dbccount"></a>DBcursor->count()</h2>
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</div>
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</div>
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</div>
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<pre class="programlisting">#include <db.h>
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int
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DBcursor->count(DBC *DBcursor, db_recno_t *countp, u_int32_t flags); </pre>
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<p>
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The <code class="methodname">DBcursor->count()</code> method returns a count of the number of data
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items for the key to which the cursor refers.
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</p>
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<p>
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The <code class="methodname">DBcursor->count()</code> <span>
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<span>
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method returns a non-zero error value on failure and 0 on success.
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</span>
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</span>
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</p>
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<div class="sect2" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h3 class="title"><a id="id3876915"></a>Parameters</h3>
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</div>
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</div>
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</div>
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<div class="sect3" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h4 class="title"><a id="id3876987"></a>countp</h4>
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</div>
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</div>
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</div>
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<p>
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The <span class="bold"><strong>countp</strong></span> parameter references
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memory into which the count of the number of duplicate data items is
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copied.
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</p>
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</div>
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<div class="sect3" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h4 class="title"><a id="id3876793"></a>flags</h4>
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</div>
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</div>
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</div>
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<p>
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The <span class="bold"><strong>flags</strong></span> parameter is currently
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unused, and must be set to 0.
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</p>
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</div>
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</div>
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<div class="sect2" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h3 class="title"><a id="id3876810"></a>Errors</h3>
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</div>
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</div>
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</div>
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<p>
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The <code class="methodname">DBcursor->count()</code> <span>
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<span>
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method may fail and return one of the following non-zero errors:
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</span>
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</span>
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</p>
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<div class="sect3" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h4 class="title"><a id="id3876980"></a> DB_REP_HANDLE_DEAD</h4>
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</div>
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</div>
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</div>
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<p>
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When a client synchronizes with the master, it is possible for committed
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transactions to be rolled back. This invalidates all the database and cursor
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handles opened in the replication environment. Once this occurs, an attempt to use
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such a handle will
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return <code class="literal">DB_REP_HANDLE_DEAD</code>.
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The application will need to discard the handle and open a new one in order to
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continue processing.
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</p>
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</div>
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<div class="sect3" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h4 class="title"><a id="id3876823"></a>DB_REP_LOCKOUT</h4>
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</div>
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</div>
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</div>
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<p>
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The operation was blocked by client/master synchronization.
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</p>
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</div>
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<div class="sect3" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h4 class="title"><a id="id3877113"></a>EINVAL</h4>
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</div>
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</div>
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</div>
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<p>
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If the cursor has not been initialized; or if an invalid flag value or parameter was specified.
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</p>
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</div>
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</div>
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<div class="sect2" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h3 class="title"><a id="id3876592"></a>Class</h3>
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</div>
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</div>
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</div>
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<p>
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<a class="link" href="dbc.html" title="Chapter 3. The DBcursor Handle">DBcursor</a>
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</p>
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</div>
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<div class="sect2" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h3 class="title"><a id="id3876826"></a>See Also</h3>
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</div>
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</div>
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</div>
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<p>
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<a class="xref" href="dbc.html#dbclist" title="Database Cursors and Related Methods">Database Cursors and Related Methods</a>
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</p>
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</div>
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</div>
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<div class="navfooter">
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<hr />
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<table width="100%" summary="Navigation footer">
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<tr>
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<td width="40%" align="left"><a accesskey="p" href="dbccmp.html">Prev</a> </td>
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<td width="20%" align="center">
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<a accesskey="u" href="dbc.html">Up</a>
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</td>
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<td width="40%" align="right"> <a accesskey="n" href="dbcdel.html">Next</a></td>
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</tr>
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<tr>
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<td width="40%" align="left" valign="top">DBcursor->cmp() </td>
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<td width="20%" align="center">
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<a accesskey="h" href="index.html">Home</a>
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</td>
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<td width="40%" align="right" valign="top"> DBcursor->del()</td>
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</tr>
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</table>
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</div>
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</body>
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</html>
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