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<b>Dbc::set_priority</b>
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<tt>
<b><pre>
#include <db_cxx.h>
<p>
int
Dbc::set_priority(DB_CACHE_PRIORITY priority);
<p>
int
Dbc::get_priority(DB_CACHE_PRIORITY *priorityp);
</pre></b>
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<b>Description: Dbc::set_priority</b>
<p>Set the cache priority for pages referenced by the
<a href="../api_cxx/dbc_class.html">Dbc</a>
handle.</p>
<p>The priority of a page biases the replacement algorithm to be more or
less likely to discard a page when space is needed in the buffer pool.
The bias is temporary, and pages will eventually be discarded if they
are not referenced again. The Dbc::set_priority method is only advisory, and does
not guarantee pages will be treated in a specific way.</p>
<p>The Dbc::set_priority method may be called at any time during the life of the
application.</p>
<p>The Dbc::set_priority method
either returns a non-zero error value
or throws an exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</p>
<b>Parameters</b> <br>
<b>priority</b><ul compact><li>The <b>priority</b> parameter must be set to one of the following
values:
<br>
<b><a name="DB_PRIORITY_VERY_LOW">DB_PRIORITY_VERY_LOW</a></b><ul compact><li>The lowest priority: pages are the most likely to be discarded.</ul>
<b><a name="DB_PRIORITY_LOW">DB_PRIORITY_LOW</a></b><ul compact><li>The next lowest priority.</ul>
<b><a name="DB_PRIORITY_DEFAULT">DB_PRIORITY_DEFAULT</a></b><ul compact><li>The default priority.</ul>
<b><a name="DB_PRIORITY_HIGH">DB_PRIORITY_HIGH</a></b><ul compact><li>The next highest priority.</ul>
<b><a name="DB_PRIORITY_VERY_HIGH">DB_PRIORITY_VERY_HIGH</a></b><ul compact><li>The highest priority: pages are the least likely to be discarded.</ul>
<br></ul>
<br>
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<br><b>Class</b>
<a href="../api_cxx/dbc_class.html">Dbc</a>
<br><b>See Also</b>
<a href="../api_cxx/dbc_list.html">Database Cursors and Related Methods</a>
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