<!--$Id: db_set_bt_minkey.so,v 10.38 2004/09/28 15:04:19 bostic Exp $--> <!--Copyright (c) 1997,2007 Oracle. All rights reserved.--> <!--See the file LICENSE for redistribution information.--> <html> <head> <title>Berkeley DB: Db::set_bt_minkey</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> <h3>Db::set_bt_minkey</h3> </td> <td align=right> <a href="../../db46-devel-4.6.21/api_cxx/api_core.html"><img src="../../db46-devel-4.6.21/images/api.gif" alt="API"></a> <a href="../../db46-devel-4.6.21/ref/toc.html"><img src="../../db46-devel-4.6.21/images/ref.gif" alt="Ref"></a></td> </tr></table> <hr size=1 noshade> <tt> <h3><pre> #include <db_cxx.h> <p> int Db::set_bt_minkey(u_int32_t bt_minkey); <p> int Db::get_bt_minkey(u_int32_t *bt_minkeyp); </pre></h3> <hr size=1 noshade> <h3>Description: Db::set_bt_minkey</h3> <p>Set the minimum number of key/data pairs intended to be stored on any single Btree leaf page.</p> <p>This value is used to determine if key or data items will be stored on overflow pages instead of Btree leaf pages. For more information on the specific algorithm used, see <a href="../../db46-devel-4.6.21/ref/am_conf/bt_minkey.html">Minimum keys per page</a>. The <b>bt_minkey</b> value specified must be at least 2; if <b>bt_minkey</b> is not explicitly set, a value of 2 is used.</p> <p>The Db::set_bt_minkey method configures a database, not only operations performed using the specified <a href="../../db46-devel-4.6.21/api_cxx/db_class.html">Db</a> handle.</p> <p>The Db::set_bt_minkey method may not be called after the <a href="../../db46-devel-4.6.21/api_cxx/db_open.html">Db::open</a> method is called. If the database already exists when <a href="../../db46-devel-4.6.21/api_cxx/db_open.html">Db::open</a> is called, the information specified to Db::set_bt_minkey will be ignored. </p> <p>The Db::set_bt_minkey 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> <h3>Parameters</h3> <dl compact> <dt><b>bt_minkey</b><dd>The <b>bt_minkey</b> parameter is the minimum number of key/data pairs intended to be stored on any single Btree leaf page. </dl> <h3>Errors</h3> <p>The Db::set_bt_minkey method may fail and throw <a href="../../db46-devel-4.6.21/api_cxx/except_class.html">DbException</a>, encapsulating one of the following non-zero errors, or return one of the following non-zero errors:</p> <dl compact> <dt>EINVAL<dd>If the method was called after <a href="../../db46-devel-4.6.21/api_cxx/db_open.html">Db::open</a> was called; or if an invalid flag value or parameter was specified. </dl> <hr size=1 noshade> <h3>Description: Db::get_bt_minkey</h3> <p>The Db::get_bt_minkey method returns the minimum number of key/data pairs intended to be stored on any single Btree leaf page.</p> <p>The Db::get_bt_minkey method may be called at any time during the life of the application.</p> <p>The Db::get_bt_minkey 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> <h3>Parameters</h3> <dl compact> <dt><b>bt_minkeyp</b><dd>The Db::get_bt_minkey method returns the minimum number of key/data pairs intended to be stored on any single Btree leaf page in <b>bt_minkeyp</b>. </dl> <hr size=1 noshade> <h3>Class</h3> <a href="../../db46-devel-4.6.21/api_cxx/db_class.html">Db</a> <h3>See Also</h3> <a href="../../db46-devel-4.6.21/api_cxx/db_list.html">Databases and Related Methods</a> </tt> <table width="100%"><tr><td><br></td><td align=right> <a href="../../db46-devel-4.6.21/api_cxx/api_core.html"><img src="../../db46-devel-4.6.21/images/api.gif" alt="API"></a><a href="../../db46-devel-4.6.21/ref/toc.html"><img src="../../db46-devel-4.6.21/images/ref.gif" alt="Ref"></a> </td></tr></table> <p><font size=1>Copyright (c) 1996,2007 Oracle. All rights reserved.</font> </body> </html>