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Release 5.2.28 on 6/10/2011
2011-09-13 17:44:24 +00:00
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<title>DbMultipleKeyDataIterator</title>
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<p>Library Version 11.2.5.2</p>
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<th colspan="3" align="center">DbMultipleKeyDataIterator</th>
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<td width="20%" align="left"><a accesskey="p" href="dbmultipledataiterator.html">Prev</a> </td>
<th width="60%" align="center">Chapter 4. 
The Dbt Handle
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<div class="sect1" lang="en" xml:lang="en">
<div class="titlepage">
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<div>
<h2 class="title" style="clear: both"><a id="dbmultiplekeydataiterator"></a>DbMultipleKeyDataIterator</h2>
</div>
</div>
</div>
<pre class="programlisting">#include &lt;db_cxx.h&gt;
class DbMultipleKeyDataIterator
{
public:
DbMultipleKeyDataIterator(const Dbt &amp;dbt);
bool next(Dbt &amp;key, Dbt &amp;data);
}; </pre>
<p>
If either of the
<a class="link" href="dbcget.html#dbcget_DB_MULTIPLE">DB_MULTIPLE</a>
or
<a class="link" href="dbcget.html#dbcget_DB_MULTIPLE_KEY">DB_MULTIPLE_KEY</a>
flags were specified to the <a class="xref" href="dbget.html" title="Db::get()">Db::get()</a> or
<a class="xref" href="dbcget.html" title="Dbc::get()">Dbc::get()</a> methods, the data
<a class="link" href="dbt.html" title="Chapter 4.  The Dbt Handle">Dbt</a> returned by those interfaces will
refer to a buffer that is filled with data. Access to that data is through these
classes.
</p>
<p>
The <code class="classname">DbMultipleDataIterator</code> class is used to iterate through data
returned using the
<a class="link" href="dbcget.html#dbcget_DB_MULTIPLE_KEY">DB_MULTIPLE_KEY</a>
flag from a database belonging to Btree or Hash access methods.
</p>
<p>
The constructor takes the <a class="xref" href="dbt.html" title="Chapter 4.  The Dbt Handle">
The Dbt Handle
</a>
returned by the call to <a class="xref" href="dbget.html" title="Db::get()">Db::get()</a>
or <a class="xref" href="dbcget.html" title="Dbc::get()">Dbc::get()</a> that used the
<a class="link" href="dbcget.html#dbcget_DB_MULTIPLE_KEY">DB_MULTIPLE_KEY</a>
flag.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
All instances of the bulk retrieval classes may be used only
once, and to traverse the bulk retrieval buffer in the forward
direction only. However, they are nondestructive, so multiple
iterators can be instantiated and used on the same returned
data <a class="link" href="dbt.html" title="Chapter 4.  The Dbt Handle">Dbt</a>.
</p>
</div>
<p>
Parameters are:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p>
<code class="literal">dbt</code>
</p>
<p>
The <span class="bold"><strong>dbt</strong></span> parameter is a
data <a class="xref" href="dbt.html" title="Chapter 4.  The Dbt Handle">
The Dbt Handle
</a>
returned by the call to <a class="xref" href="dbget.html" title="Db::get()">Db::get()</a>
or <a class="xref" href="dbcget.html" title="Dbc::get()">Dbc::get()</a> that used the
<a class="link" href="dbcget.html#dbcget_DB_MULTIPLE_KEY">DB_MULTIPLE_KEY</a>
flag.
</p>
</li>
</ul>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="dbmultiplekeydataiterator.next"></a>DbMultipleKeyDataIterator.next()</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DbMultipleKeyDataIterator.next()</code> method
returns the next data item in the original bulk retrieval buffer.
</p>
<p>
The <code class="methodname">DbMultipleKeyDataIterator.next()</code> method
method returns <code class="literal">false</code> if no more data are available, and
<code class="literal">true</code> otherwise.
</p>
<p>
Parameters are:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p>
<code class="literal">key</code>
</p>
<p>
The <span class="bold"><strong>key</strong></span> parameter is a
<a class="xref" href="dbt.html" title="Chapter 4.  The Dbt Handle">
The Dbt Handle
</a>
that will be filled in with a reference to a buffer, a
size, and an offset that together yield the next data item
in the original bulk retrieval buffer.
</p>
</li>
<li>
<p>
<code class="literal">data</code>
</p>
<p>
The <span class="bold"><strong>data</strong></span> parameter is a
<a class="xref" href="dbt.html" title="Chapter 4.  The Dbt Handle">
The Dbt Handle
</a>
that will be filled in with a reference to a buffer, a
size, and an offset that together yield the next data item
in the original bulk retrieval buffer.
</p>
</li>
</ul>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
Release 5.2.36 on 9/14/2022
2011-12-20 00:07:10 +00:00
<h3 class="title"><a id="id3590621"></a>Class</h3>
Release 5.2.28 on 6/10/2011
2011-09-13 17:44:24 +00:00
</div>
</div>
</div>
<p>
<a class="link" href="dbmultipleiterator.html" title="DbMultipleIterator">DbMultipleIterator</a>
</p>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
Release 5.2.36 on 9/14/2022
2011-12-20 00:07:10 +00:00
<h3 class="title"><a id="id3590542"></a>See Also</h3>
Release 5.2.28 on 6/10/2011
2011-09-13 17:44:24 +00:00
</div>
</div>
</div>
<p>
<a class="xref" href="dbt.html#dbtlist" title="DBT and Bulk Operations">DBT and Bulk Operations</a>
</p>
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