Rollback Segments store transactions that are in progress. They are used to back out transactions which were applied to the database due to lack of space in the database buffer cache in memory but are not committed . They are also extremely sensitive to storage space problems in instances that process large transactions
Trigger Applications on the same object. When a validate-event or pre-event is fired on an object, then that object becomes locked until the transaction has been committed to the database. If you try to spawn another Dimensions command, then you run the following risks.
An online redo log is a set of two or more online log files that record all committed changes made to the database. Whenever a transaction is committed , the corresponding redo entries temporarily stored in redo log buffers of the system global area are written to an online redo log file by the background process LGWR.
WHen statement executes, it should return a message that one row has been deleted. In this case user will need to run .... commit ;... to commit the transaction . These steps will resolve this issue.
