as transaction is used when we failed commited sth, the transaction will do the rollback action to protect data.
but when doing query in DB, we don't need anything rollback, so why hibernate still using transaction in this case? is it will influence the performance? I get puzzled.
thank you for anyone's help! : )

linna.

The database uses transactions anyway to maintain data integrity. The locking implementation varies from vendor to vendor. Use the transaction API. It will is the correct way to access a transactional resource.