What is true about “UNDO DATA” in the context of database backups in Oracle 11g using RMAN?
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COMMITTED UNDO data is NEVER backed up
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COMMITTED UNDO data is backed up depending on the status of the transaction
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COMMITTED UNDO data is backed up always
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UNCOMMITTED UNDO data is never backed up
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UNCOMMITTED UNDO data is backed up depending on the status of the transaction
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UNCOMMITTED UNDO data is backed up always
RMAN's backup behavior for undo data follows specific rules. COMMITTED UNDO data is never backed up because it's no longer needed for recovery (option A is correct). UNCOMMITTED UNDO data is always backed up to enable transaction rollback after restore (option F is correct). Options B, C, D, and E are incorrect because they misstate when undo data is included in backups. This distinction ensures proper recovery capabilities.
RMAN's backup optimization skips undo blocks belonging to already-COMMITTED transactions when it can determine they are no longer needed for recovery consistency — Oracle's documentation confirms committed undo generally isn't required for datafile recovery, so RMAN excludes it, matching 'COMMITTED UNDO data is NEVER backed up.' Conversely, UNCOMMITTED undo (undo for active/in-flight transactions) must always be backed up, because it may be needed to roll back that transaction during recovery — matching 'UNCOMMITTED UNDO data is backed up always.' The other options (committed undo backed up 'depending on status' or 'always', uncommitted 'never' or 'depending on status') contradict this fixed RMAN behavior around undo segment handling.