import com.sleepycat.db.*;

public int del(DbTxn txnid, Dbt key, int flags)
    throws DbException;

Description

The Db.del method removes key/data pairs from the database. The key/data pair associated with the specified key is discarded from the database. In the presence of duplicate key values, all records associated with the designated key will be discarded.

When called on a database that has been made into a secondary index using the Db.associate method, the Db.del method deletes the key/data pair from the primary database and all secondary indices.

If the operation is to be transaction-protected (other than by specifying the Db.DB_AUTO_COMMIT flag), the txnid parameter is a transaction handle returned from DbEnv.txn_begin; otherwise, null.

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

Db.DB_AUTO_COMMIT

Enclose the Db.del 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.

If the specified key is not in the database, the Db.del method will return Db.DB_NOTFOUND. Otherwise, the Db.del method throws an exception that encapsulates a non-zero error value on failure.

Errors

The Db.del method may fail and throw an exception encapsulating a non-zero error for the following conditions:

Db.DB_SECONDARY_BAD

A secondary index references a nonexistent primary key.

EACCES

An attempt was made to modify a read-only database.

EINVAL

An invalid flag value or parameter was specified.

If the operation was selected to resolve a deadlock, the Db.del method will fail and throw a DbDeadlockException exception.

The Db.del method may fail and throw an exception for errors specified for other Berkeley DB and C library or system methods. If a catastrophic error has occurred, the Db.del method may fail and throw a DbRunRecoveryException, in which case all subsequent Berkeley DB calls will fail in the same way.

Class

See Also