Edit File: db_set_priority.html
<!--$Id: db_set_priority.so,v 1.1 2007/05/22 18:06:05 bostic Exp $--> <!--Copyright (c) 1997,2008 Oracle. All rights reserved.--> <!--See the file LICENSE for redistribution information.--> <html> <head> <title>Berkeley DB: Db::set_priority</title> <meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> <meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> </head> <body bgcolor=white> <table width="100%"><tr valign=top> <td> <b>Db::set_priority</b> </td> <td align=right> <a href="../../db4-devel-4.7.25/api_cxx/api_core.html"><img src="../../db4-devel-4.7.25/images/api.gif" alt="API"></a> <a href="../../db4-devel-4.7.25/ref/toc.html"><img src="../../db4-devel-4.7.25/images/ref.gif" alt="Ref"></a></td> </tr></table> <hr size=1 noshade> <tt> <b><pre> #include <db_cxx.h> <p> int Db::set_priority(DB_CACHE_PRIORITY priority); <p> int Db::get_priority(DB_CACHE_PRIORITY *priorityp); </pre></b> <hr size=1 noshade> <b>Description: Db::set_priority</b> <!--$Id: dbc_set_priority.so,v 1.3 2007/05/22 18:06:05 bostic Exp $--> <p>Set the cache priority for pages referenced by the <a href="../../db4-devel-4.7.25/api_cxx/db_class.html">Db</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 Db::set_priority method is only advisory, and does not guarantee pages will be treated in a specific way.</p> <p>The Db::set_priority method may be called at any time during the life of the application.</p> <p>The Db::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> <hr size=1 noshade> <br><b>Class</b> <a href="../../db4-devel-4.7.25/api_cxx/db_class.html">Db</a> <br><b>See Also</b> <a href="../../db4-devel-4.7.25/api_cxx/db_list.html">Databases and Related Methods</a> </tt> <table width="100%"><tr><td><br></td><td align=right> <a href="../../db4-devel-4.7.25/api_cxx/api_core.html"><img src="../../db4-devel-4.7.25/images/api.gif" alt="API"></a><a href="../../db4-devel-4.7.25/ref/toc.html"><img src="../../db4-devel-4.7.25/images/ref.gif" alt="Ref"></a> </td></tr></table> <p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> </body> </html>
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