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<h2 class="title" style="clear: both"><a id="dbccount"></a>Dbc::count()</h2>
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<pre class="programlisting">#include <db_cxx.h>
int
Dbc::count(db_recno_t *countp, u_int32_t flags);</pre>
<p>
The <code class="methodname">Dbc::count()</code> method returns a count of the number of data
items for the key to which the cursor refers.
</p>
<p>
The <code class="methodname">Dbc::count()</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="id1655234"></a>Parameters</h3>
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<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1655232"></a>countp</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>countp</strong></span> parameter references
memory into which the count of the number of duplicate data items is
copied.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1655559"></a>flags</h4>
</div>
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<p>
The <span class="bold"><strong>flags</strong></span> parameter is currently
unused, and must be set to 0.
</p>
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<h3 class="title"><a id="id1655574"></a>Errors</h3>
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<p>
The <code class="methodname">Dbc::count()</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>
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<h4 class="title"><a id="id1655440"></a><span>DbRepHandleDeadException or</span> DB_REP_HANDLE_DEAD</h4>
</div>
</div>
</div>
<p>
When a client synchronizes with the master, it is possible for committed
transactions to be rolled back. This invalidates all the database and cursor
handles opened in the replication environment. Once this occurs, an attempt to use
such a handle will
<span>
throw a <a class="xref" href="dbrephandledead.html" title="DbRepHandleDeadException">DbRepHandleDeadException</a> (if
your application is configured to throw exceptions), or
</span>
return <code class="literal">DB_REP_HANDLE_DEAD</code>.
The application will need to discard the handle and open a new one in order to
continue processing.
</p>
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<div class="sect3" lang="en" xml:lang="en">
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<div>
<div>
<h4 class="title"><a id="id1655590"></a><span>DbDeadlockException or </span>DB_REP_LOCKOUT</h4>
</div>
</div>
</div>
<p>
The operation was blocked by client/master synchronization.
</p>
<p>
<a class="xref" href="dbdeadlock.html" title="DbDeadlockException">DbDeadlockException</a> is thrown if
your Berkeley DB API is configured to throw exceptions.
Otherwise, <code class="literal">DB_REP_LOCKOUT</code> is returned.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1655584"></a>EINVAL</h4>
</div>
</div>
</div>
<p>
If the cursor has not been initialized; or if an invalid flag value or parameter was specified.
</p>
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<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
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<div>
<h3 class="title"><a id="id1655659"></a>Class</h3>
</div>
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<p>
<a class="link" href="dbc.html" title="Chapter 3. The Dbc Handle">Dbc</a>
</p>
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<h3 class="title"><a id="id1655624"></a>See Also</h3>
</div>
</div>
</div>
<p>
<a class="xref" href="dbc.html#dbclist" title="Database Cursors and Related Methods">Database Cursors and Related Methods</a>
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