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<h1>DBT: Bulk Retrieval</h1>
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<p>If either of the <a href="../api_c/dbc_get.html#DB_MULTIPLE">DB_MULTIPLE</a> or <a href="../api_c/dbc_get.html#DB_MULTIPLE_KEY">DB_MULTIPLE_KEY</a> flags
were specified to the <a href="../api_c/db_get.html">DB->get</a> or <a href="../api_c/dbc_get.html">DBcursor->c_get</a> methods, the data
<a href="../api_c/dbt_class.html">DBT</a> returned by those interfaces will refer to a buffer that
is filled with data. Access to that data is through the following
macros:
<p><dl compact>
<p><dt><a name="DB_MULTIPLE_INIT">DB_MULTIPLE_INIT</a><dd><pre>DB_MULTIPLE_INIT(void *pointer, <a href="../api_c/dbt_class.html">DBT</a> *data);</pre>
<p>Initialize the retrieval. The <b>pointer</b> argument is a variable
to be initialized. The <b>data</b> argument is a <a href="../api_c/dbt_class.html">DBT</a> structure
returned from a successful call to <a href="../api_c/db_get.html">DB->get</a> or <a href="../api_c/dbc_get.html">DBcursor->c_get</a>
for which one of the <a href="../api_c/dbc_get.html#DB_MULTIPLE">DB_MULTIPLE</a> or <a href="../api_c/dbc_get.html#DB_MULTIPLE_KEY">DB_MULTIPLE_KEY</a>
flags was specified.
<p><dt><a name="DB_MULTIPLE_NEXT">DB_MULTIPLE_NEXT</a><dd><pre>DB_MULTIPLE_NEXT(void *pointer, <a href="../api_c/dbt_class.html">DBT</a> *data, void *retdata, size_t retdlen);</pre>
<p>The <b>data</b> argument is a <a href="../api_c/dbt_class.html">DBT</a> structure returned from a
successful call to <a href="../api_c/db_get.html">DB->get</a> or <a href="../api_c/dbc_get.html">DBcursor->c_get</a> for which the
<a href="../api_c/dbc_get.html#DB_MULTIPLE">DB_MULTIPLE</a> flag was specified. The <b>pointer</b> and
<b>data</b> arguments must have been previously initialized by a call
to DB_MULTIPLE_INIT. The <b>retdata</b> argument is set to
refer to the next data element in the returned set, and the
<b>retdlen</b> argument is set to the length, in bytes, of that data
element. When used with the Queue and Recno access methods,
<b>retdata</b> will be set to NULL for deleted records. The
<b>pointer</b> argument is set to NULL if there are no more data
elements in the returned set.
<p><dt><a name="DB_MULTIPLE_KEY_NEXT">DB_MULTIPLE_KEY_NEXT</a><dd><pre>DB_MULTIPLE_KEY_NEXT(void *pointer, <a href="../api_c/dbt_class.html">DBT</a> *data,
void *retkey, size_t retklen, void *retdata, size_t retdlen);</pre>
<p>The <b>data</b> argument is a <a href="../api_c/dbt_class.html">DBT</a> structure returned from a
successful call to <a href="../api_c/db_get.html">DB->get</a> or <a href="../api_c/dbc_get.html">DBcursor->c_get</a> for which the
<a href="../api_c/dbc_get.html#DB_MULTIPLE_KEY">DB_MULTIPLE_KEY</a> flag was specified. The <b>pointer</b> and
<b>data</b> arguments must have been previously initialized by a call
to DB_MULTIPLE_INIT. The <b>retkey</b> argument is set to
refer to the next key element in the returned set, and the
<b>retklen</b> argument is set to the length, in bytes, of that key
element. The <b>retdata</b> argument is set to refer to the next data
element in the returned set, and the <b>retdlen</b> argument is set to
the length, in bytes, of that data element. The <b>pointer</b>
argument is set to NULL if there are no more key/data pairs in the
returned set.
<p><dt><a name="DB_MULTIPLE_RECNO_NEXT">DB_MULTIPLE_RECNO_NEXT</a><dd><pre>DB_MULTIPLE_RECNO_NEXT(void *pointer, <a href="../api_c/dbt_class.html">DBT</a> *data,
db_recno_t recno, void * retdata, size_t retdlen);</pre>
<p>The <b>data</b> argument is a <a href="../api_c/dbt_class.html">DBT</a> structure returned from a
successful call to <a href="../api_c/db_get.html">DB->get</a> or <a href="../api_c/dbc_get.html">DBcursor->c_get</a> for which the
<a href="../api_c/dbc_get.html#DB_MULTIPLE_KEY">DB_MULTIPLE_KEY</a> flag was specified. The <b>pointer</b> and
<b>data</b> arguments must have been previously initialized by a call
to DB_MULTIPLE_INIT. The <b>recno</b> argument is set to the
record number of the next record in the returned set. The
<b>retdata</b> argument is set to refer to the next data element in
the returned set, and the <b>retdlen</b> argument is set to the length,
in bytes, of that data element. When used with the Queue and Recno
access methods, <b>retdata</b> will be set to NULL for deleted
records. The <b>pointer</b> argument is set to NULL if there are
no more key/data pairs in the returned set.
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