import com.sleepycat.db.*;

public void set_lk_detect(int detect)
	throws DbException;

Description

Set if the deadlock detector is to be run whenever a lock conflict occurs, and specify which transaction should be aborted in the case of a deadlock. The specified value must be one of the following list:

Db.DB_LOCK_DEFAULT

Use the default policy as specified by db_deadlock.

Db.DB_LOCK_MAXLOCKS

Abort the transaction with the greatest number of locks.

Db.DB_LOCK_MINLOCKS

Abort the transaction with the fewest locks.

Db.DB_LOCK_MINWRITE

Abort the transaction with the fewest write locks.

Db.DB_LOCK_OLDEST

Abort the oldest transaction.

Db.DB_LOCK_RANDOM

Abort a random transaction involved in the deadlock.

Db.DB_LOCK_YOUNGEST

Abort the youngest transaction.

The DbEnv.set_lk_detect interface may be used only to configure Berkeley DB before the DbEnv.open interface is called.

The DbEnv.set_lk_detect method throws an exception that encapsulates a non-zero error value on failure.

The database environment's deadlock detector configuration may also be set using the environment's DB_CONFIG file. The syntax of the entry in that file is a single line with the string "set_lk_detect", one or more whitespace characters, and the interface detect argument as a string; for example, "set_lk_detect DB_LOCK_OLDEST". Because the DB_CONFIG file is read when the database environment is opened, it will silently overrule configuration done before that time.

Errors

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

EINVAL

An invalid flag value or parameter was specified.

Called after DbEnv.open was called.

The DbEnv.set_lk_detect 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 DbEnv.set_lk_detect method may fail and throw a DbRunRecoveryException, in which case all subsequent Berkeley DB calls will fail in the same way.

Class

See Also