DbEnv::dbremove()

#include <db_cxx.h>
 
int
DbEnv::dbremove(DbTxn *txnid,
    const char *file, const char *database, u_int32_t flags);

The DbEnv::dbremove() method removes the database specified by the file and database parameters. If no database is specified, the underlying file represented by file is removed, incidentally removing all of the databases it contained.

Applications should never remove databases with open Db handles, or in the case of removing a file, when any database in the file has an open handle.

The DbEnv::dbremove() method is not atomic in a sliced environment. If the operation fails, it is possible for some, but not all, of the sliced databases to still exist.

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.

DbEnv::dbremove() is affected by any database directory specified using the DbEnv::add_data_dir() method, or by setting the add_data_dir string in the environment's DB_CONFIG file.

Parameters

txnid

If the operation is part of an application-specified transaction, the txnid parameter is a transaction handle returned from DbEnv::txn_begin() ; if the operation is part of a Berkeley DB Concurrent Data Store group, the txnid parameter is a handle returned from DbEnv::cdsgroup_begin() ; otherwise NULL. If no transaction handle is specified, but the DB_AUTO_COMMIT flag is specified to either this method or the environment handle, the operation will be implicitly transaction protected.

file

The file parameter is the physical file which contains the database(s) to be removed.

database

The database parameter is the database to be removed.

flags

The flags parameter must be set to 0 or the following value:

  • DB_AUTO_COMMIT

    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.

Environment Variables

The environment variable DB_HOME may be used as the path of the database environment home.

Errors

The DbEnv::dbremove() method may fail and throw a DbException exception, encapsulating one of the following non-zero errors, or return one of the following non-zero errors:

DbDeadlockException or DB_LOCK_DEADLOCK

A transactional database environment operation was selected to resolve a deadlock.

DbDeadlockException is thrown if your Berkeley DB API is configured to throw exceptions. Otherwise, DB_LOCK_DEADLOCK is returned.

DbLockNotGrantedException or DB_LOCK_NOTGRANTED

A Berkeley DB Concurrent Data Store database environment configured for lock timeouts was unable to grant a lock in the allowed time.

You attempted to open a database handle that is configured for no waiting exclusive locking, but the exclusive lock could not be immediately obtained. See Db::set_lk_exclusive() for more information.

DbLockNotGrantedException is thrown if your Berkeley DB API is configured to throw exceptions. Otherwise, DB_LOCK_NOTGRANTED is returned.

EINVAL

If the method was called before DbEnv::open() was called; or if an invalid flag value or parameter was specified.

ENOENT

The file or directory does not exist.

DB_META_CHKSUM_FAIL

Checksum mismatch detected on a database metadata page. Either the database is corrupted or the file is not a Berkeley DB database file.

Class

DbEnv

See Also

Database Environments and Related Methods