libdb/docs/api_reference/C/dbccount.html
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The DBcursor Handle
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<h2 class="title" style="clear: both"><a id="dbccount"></a>DBcursor-&gt;count()</h2>
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<pre class="programlisting">#include &lt;db.h&gt;
int
DBcursor-&gt;count(DBC *DBcursor, db_recno_t *countp, u_int32_t flags); </pre>
<p>
The <code class="methodname">DBcursor-&gt;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">DBcursor-&gt;count()</code> <span>
<span>
method returns a non-zero error value on failure and 0 on success.
</span>
</span>
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<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id3696898"></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="id3696905"></a>countp</h4>
</div>
</div>
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<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">
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<h4 class="title"><a id="id3696075"></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.
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<div class="sect2" lang="en" xml:lang="en">
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<h3 class="title"><a id="id3696724"></a>Errors</h3>
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<p>
The <code class="methodname">DBcursor-&gt;count()</code> <span>
<span>
method may fail and return one of the following non-zero errors:
</span>
</span>
</p>
<div class="sect3" lang="en" xml:lang="en">
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<h4 class="title"><a id="id3696901"></a> DB_REP_HANDLE_DEAD</h4>
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</div>
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<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
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>
</div>
<div class="sect3" lang="en" xml:lang="en">
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<h4 class="title"><a id="id3696761"></a>DB_REP_LOCKOUT</h4>
</div>
</div>
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<p>
The operation was blocked by client/master synchronization.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id3697031"></a>EINVAL</h4>
</div>
</div>
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<p>
If the cursor has not been initialized; or if an invalid flag value or parameter was specified.
</p>
</div>
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<div class="sect2" lang="en" xml:lang="en">
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<h3 class="title"><a id="id3696749"></a>Class</h3>
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<a class="link" href="dbc.html" title="Chapter 3.  The DBcursor Handle">DBcursor</a>
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<h3 class="title"><a id="id3696626"></a>See Also</h3>
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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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