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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="dbmultipledatabuilder"></a>DbMultipleDataBuilder</h2>
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</div>
<pre class="programlisting">#include <db_cxx.h>
class DbMultipleDataBuilder
{
public:
DbMultipleDataBuilder(Dbt &dbt);
bool append(void *dbuf, size_t dlen);
bool reserve(void *&ddest, size_t dlen);
}; </pre>
<p>
This class builds a bulk buffer for use when the
<a class="link" href="dbput.html#put_DB_MULTIPLE">DB_MULTIPLE</a>
flag is specified to either the
<a class="xref" href="dbput.html" title="Db::put()">Db::put()</a> or
<a class="xref" href="dbdel.html" title="Db::del()">Db::del()</a> methods. The buffer in
the <a class="link" href="dbt.html" title="Chapter 4. The Dbt Handle">Dbt</a> passed to the constructor is
filled by calls to
<a class="xref" href="dbmultipledatabuilder.html#dbmultipledatabuilder.append" title="DbMultipleDataBuilder.append()">DbMultipleDataBuilder.append()</a>
or
<a class="xref" href="dbmultipledatabuilder.html#dbmultipledatabuilder.reserve" title="DbMultipleDataBuilder.reserve()">DbMultipleDataBuilder.reserve()</a>.
</p>
<p>
The constructor takes a <a class="xref" href="dbt.html" title="Chapter 4. The Dbt Handle">
The Dbt Handle
</a>
that must be configured to contain a buffer managed by the application,
with the <code class="literal">ulen</code> field set to the size of the buffer.
</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 build the bulk buffer in the forward direction only.
</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 <a class="xref" href="dbt.html" title="Chapter 4. The Dbt Handle">
The Dbt Handle
</a> that must already be configured to contain a buffer managed by the application, with the <code class="literal">ulen</code> field set to the size of the buffer, which must be a multiple of 4.
</p>
</li>
</ul>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="dbmultipledatabuilder.append"></a>DbMultipleDataBuilder.append()</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DbMultipleDataBuilder.append()</code> method
copies a data item to the end of the buffer.
</p>
<p>
The <code class="methodname">DbMultipleDataBuilder.append()</code>
method returns <code class="literal">false</code> if the data does not fit
in the buffer and <code class="literal">true</code> otherwise.
</p>
<p>
Parameters are:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p>
<code class="literal">dbuf</code>
</p>
<p>
A pointer to the data to be copied into the bulk buffer.
</p>
</li>
<li>
<p>
<code class="literal">dlen</code>
</p>
<p>
The number of bytes to be copied.
</p>
</li>
</ul>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="dbmultipledatabuilder.reserve"></a>DbMultipleDataBuilder.reserve()</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DbMultipleDataBuilder.reserve()</code>
method reserves space for the next data item in the bulk buffer.
Unlike the <code class="methodname">append()</code>, no data is actually
copied into the bulk buffer by <code class="methodname">reserve()</code>:
copying the data is the responsibility of the application.
</p>
<p>
The <code class="methodname">DbMultipleDataBuilder.reserve()</code>
method returns <code class="literal">false</code> if the data does
not fit in the buffer and <code class="literal">true</code> otherwise.
</p>
<p>
Parameters are:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p>
<code class="literal">ddest</code>
</p>
<p>
Set to a pointer to the position in the bulk buffer reserved for the data item, if enough space is available.
</p>
</li>
<li>
<p>
<code class="literal">dlen</code>
</p>
<p>
The number of bytes to reserve.
</p>
</li>
</ul>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp6514520"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="dbt.html" title="Chapter 4. The Dbt Handle">Dbt</a>
</p>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp6468120"></a>See Also</h3>
</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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