<!--$Id: env_dbremove.html,v 1.2 2004/03/30 01:21:57 jtownsen Exp $--> <!--Copyright 1997-2003 by Sleepycat Software, Inc.--> <!--All rights reserved.--> <!--See the file LICENSE for redistribution information.--> <html> <head> <title>Berkeley DB: DbEnv::dbremove</title> <meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> <meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> </head> <body bgcolor=white> <a name="2"><!--meow--></a> <table width="100%"><tr valign=top> <td> <h3>DbEnv::dbremove</h3> </td> <td align=right> <a href="../api_cxx/api_index.html"><img src="../images/api.gif" alt="API"></a> <a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a> </td></tr></table> <hr size=1 noshade> <tt> <h3><pre> #include <db_cxx.h> <p> int DbEnv::dbremove(DbTxn *txnid, const char *file, const char *database, u_int32_t flags); </pre></h3> <hr size=1 noshade> <h3>Description: DbEnv::dbremove</h3> <p>The DbEnv::dbremove method removes the database specified by the <b>file</b> and <b>database</b> parameters. If no <b>database</b> is specified, the underlying file represented by <b>file</b> is removed, incidentally removing all of the databases it contained.</p> <p>Applications should never remove databases with open <a href="../api_cxx/db_class.html">Db</a> handles, or in the case of removing a file, when any database in the file has an open handle. For example, some architectures do not permit the removal of files with open system handles. On these architectures, attempts to remove databases currently in use by any thread of control in the system will fail.</p> <p>The DbEnv::dbremove 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> <p><dl compact> <p><dt><b>database</b><dd> The <b>database</b> parameter is the database to be removed. <p><dt><b>file</b><dd> The <b>file</b> parameter is the physical file which contains the database(s) to be removed. <p><dt><b>flags</b><dd> The <b>flags</b> parameter must be set to 0 or the following value: <p><dl compact> <p><dt><a name="DB_AUTO_COMMIT">DB_AUTO_COMMIT</a><dd>Enclose the DbEnv::dbremove call within a transaction. If the call succeeds, changes made by the operation will be recoverable. If the call fails, the operation will have made no changes. </dl> <p><dt><b>txnid</b><dd> If the operation is to be transaction-protected, the <b>txnid</b> parameter is a transaction handle returned from <a href="../api_cxx/txn_begin.html">DbEnv::txn_begin</a>; otherwise, NULL. </dl> <h3>Environment Variables</h3> <p>The environment variable <b>DB_HOME</b> may be used as the path of the database environment home.</p> <p>DbEnv::dbremove is affected by any database directory specified using the <a href="../api_cxx/env_set_data_dir.html">DbEnv::set_data_dir</a> method, or by setting the "set_data_dir" string in the environment's <b>DB_CONFIG</b> file.</p> <h3>Errors</h3> <p>The DbEnv::dbremove method may fail and throw <a href="../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> <p><dl compact> <p><dt>DB_FILEOPEN<dd>An attempt was made to remove the underlying file and a database in the file was currently open. </dl> <p><dl compact> <p><dt>EINVAL<dd>If DbEnv::dbremove called before <a href="../api_cxx/env_open.html">DbEnv::open</a> was called; or if an invalid flag value or parameter was specified. </dl> <p><dl compact> <p><dt>ENOENT<dd>The file or directory does not exist. </dl> <p>If a transactional database environment operation was selected to resolve a deadlock, the DbEnv::dbremove method will fail and either return <a href="../ref/program/errorret.html#DB_LOCK_DEADLOCK">DB_LOCK_DEADLOCK</a> or throw a <a href="../api_cxx/deadlock_class.html">DbDeadlockException</a> exception.</p> <p>If a Berkeley DB Concurrent Data Store database environment configured for lock timeouts was unable to grant a lock in the allowed time, the DbEnv::dbremove method will fail and either return <a href="../ref/program/errorret.html#DB_LOCK_NOTGRANTED">DB_LOCK_NOTGRANTED</a> or throw a <a href="../api_cxx/lockng_class.html">DbLockNotGrantedException</a> exception.</p> <hr size=1 noshade> <h3>Class</h3> <a href="../api_cxx/env_class.html">DbEnv</a> <h3>See Also</h3> <a href="../api_cxx/env_list.html">Database Environments and Related Methods</a> </tt> <table width="100%"><tr><td><br></td><td align=right> <a href="../api_cxx/api_index.html"><img src="../images/api.gif" alt="API"></a><a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a> </td></tr></table> <p><font size=1><a href="../sleepycat/legal.html">Copyright (c) 1996-2003</a> <a href="http://www.sleepycat.com">Sleepycat Software, Inc.</a> - All rights reserved.</font> </body> </html>