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Rollback segments store information about a database transaction while it is occurring. In the event that a transaction fails to complete, this information will be used to “roll back” the database to its condition prior to the transaction.  Rollback segments also provide read consistency for long-running queries where the base tables may have been altered by other sessions in the interim.

Properly functioning rollback segments are vital for ensuring database integrity. VROOM allows you to examine the attributes of the rollback segments, as well as infer details about recent database transaction rates.

Starting with Oracle 9i, undo segments were offered as an alternative to conventional rollback segments.  Undo segments offer more flexibility than rollback segments by permitting a specific minimum retention time for rollback information.

For databases utilizing undo segments, VROOM provides additional information about the number of transactions recorded and undo blocks consumed during each retention period. This provides a raw estimate of the timeframe and scope of transactional activity in the database. This can also be used to determine the optimal sizing for undo tablespaces.

[VROOM!] [SESSION INFO] [STORAGE MANAGEMENT] [PERFORMANCE TUNING] [BACKUP & RECOVERY] [ROLLBACK & UNDO] [REDO LOGS] [CONTROL FILES] [SCHEMA OBJECTS] [REPORTING] [WIZARDS] [DOCUMENTATION] [DOWNLOAD]