I would like to know different isolation levels with respect to commit, and would also like to know about row-level and table-level lock.
ANSI/ISO SQL defines four isolation levels:
According to Oracle's Database Development Guide, chapter 6.6.1: Transaction Interaction and Isolation Level, you can request either isolation level READ COMMITTED
(the default) or SERIALIZABLE
.
Please note, however, that what Oracle call SERIALIZABLE
is actually snapshot isolation.
For more information about row-level and table-level locks, see Overview of the Oracle Database Locking Mechanism and Locking tables explicitly.