Releasing of Locks
A transaction accumulates locks on resources until commit or rollback, when all the locks accumulated during the transaction are released.
A transaction is committed by one of the following:
• Issuing the COMMIT statement after one or more SQL statements
• Using the SET AUTOCOMMIT ON statement
• Ending the session
A rollback aborts the transaction and releases accumulated locks.
After a commit or rollback, the current transaction is terminated and a new transaction is started as soon as the next SQL statement is issued.
Note: If SET AUTOCOMMIT OFF has been set for the session and a commit statement is not issued: all locks are held until the session ends. The entire session is one transaction which can lead to concurrency problems.