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<div class="sect1" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="dbmultiplerecnodatabuilder"></a>DbMultipleRecnoDataBuilder</h2></div></div></div><pre class="programlisting">#include <db_cxx.h>
class DbMultipleRecnoDataBuilder
{
public:
DbMultipleRecnoDataBuilder(Dbt &dbt);
bool append(db_recno_t recno, void *dbuf, size_t dlen);
bool reserve(db_recno_t recno, 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_KEY">DB_MULTIPLE_KEY</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 with the recno
or queue access methods, or for the <code class="literal">key</code> when the
<a class="link" href="dbput.html#put_DB_MULTIPLE">DB_MULTIPLE</a> flag is used. 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="dbmultiplerecnodatabuilder.html#dbmultiplerecnodatabuilder.append" title="DbMultipleRecnoDataBuilder.append()">DbMultipleRecnoDataBuilder.append()</a>
or
<a class="xref" href="dbmultiplerecnodatabuilder.html#dbmultiplerecnodatabuilder.reserve" title="DbMultipleRecnoDataBuilder.reserve()">DbMultipleRecnoDataBuilder.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>
bool append(db_recno_t recno, void *dbuf, size_t dlen);
<div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="dbmultiplerecnodatabuilder.append"></a>DbMultipleRecnoDataBuilder.append()</h3></div></div></div><p>
The <code class="methodname">DbMultipleRecnoDataBuilder.append()</code>
method copies a record number / data pair to the end of the buffer.
</p><p>
The <code class="methodname">DbMultipleRecnoDataBuilder.append()</code>
method returns <code class="literal">false</code> if the record
number / data pair 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">recno</code>
</p><p>
The record number to append.
</p></li><li><p>
<code class="literal">dbuf</code>
</p><p>
A pointer to the data item to be copied into the bulk
buffer.
</p></li><li><p>
<code class="literal">dlen</code>
</p><p>
The number of bytes of the data item 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="dbmultiplerecnodatabuilder.reserve"></a>DbMultipleRecnoDataBuilder.reserve()</h3></div></div></div><p>
The <code class="methodname">DbMultipleRecnoDataBuilder.reserve()</code>
method reserves space for the next record number / data pair in
the bulk buffer. The record number is appended, but unlike the
<code class="methodname">append()</code>, the data is not 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">DbMultipleRecnoDataBuilder.reserve()</code>
method returns <code class="literal">false</code> if the record 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">recno</code>
</p><p>
The record number to append.
</p></li><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 for the data item.
</p></li></ul></div></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="idp6554296"></a>Class</h3></div></div></div><p>
<a class="link" href="dbmultiplebuilder.html" title="DbMultipleBuilder">DbMultipleBuilder</a>
</p></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="idp6564664"></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></div></div>
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