Rollback segments are one of the least understood areas in database tuning for many DBAs.
Most DBAs pay very little attention to tuning rollback segments. Tuning Rollback segment requires a greater understanding of the internal workings of oracle and are difficult to tune by normal means. This note gives a brief introduction to transactions and rollback segments and goes beyond the basics of rollback segment is used for transaction rollback , so the reader is familiar with what is going on inside a rollback segment. A database read, modify and write life cycle is called a transaction. A Rollback entry is made for all transactions unless specific clauses are specified.