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13<b>Dbc::set_priority</b>
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20<tt>
21<b><pre>
22#include &lt;db_cxx.h&gt;
23<p>
24int
25Dbc::set_priority(DB_CACHE_PRIORITY priority);
26<p>
27int
28Dbc::get_priority(DB_CACHE_PRIORITY *priorityp);
29</pre></b>
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31<b>Description: Dbc::set_priority</b>
32<p>Set the cache priority for pages referenced by the
33<a href="../api_cxx/dbc_class.html">Dbc</a>
34handle.</p>
35<p>The priority of a page biases the replacement algorithm to be more or
36less likely to discard a page when space is needed in the buffer pool.
37The bias is temporary, and pages will eventually be discarded if they
38are not referenced again.  The Dbc::set_priority method is only advisory, and does
39not guarantee pages will be treated in a specific way.</p>
40<p>The Dbc::set_priority method may be called at any time during the life of the
41application.</p>
42<p>The Dbc::set_priority method
43either returns a non-zero error value
44or throws an exception that encapsulates a non-zero error value on
45failure, and returns 0 on success.
46</p>
47<b>Parameters</b> <br>
48 <b>priority</b><ul compact><li>The <b>priority</b> parameter must be set to one of the following
49values:
50<br>
51<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>
52<b><a name="DB_PRIORITY_LOW">DB_PRIORITY_LOW</a></b><ul compact><li>The next lowest priority.</ul>
53<b><a name="DB_PRIORITY_DEFAULT">DB_PRIORITY_DEFAULT</a></b><ul compact><li>The default priority.</ul>
54<b><a name="DB_PRIORITY_HIGH">DB_PRIORITY_HIGH</a></b><ul compact><li>The next highest priority.</ul>
55<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>
56<br></ul>
57<br>
58<hr size=1 noshade>
59<br><b>Class</b>
60<a href="../api_cxx/dbc_class.html">Dbc</a>
61<br><b>See Also</b>
62<a href="../api_cxx/dbc_list.html">Database Cursors and Related Methods</a>
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