Database Administrators Stack Exchange is a question and answer site for database professionals who wish to improve their database skills and learn from others in the community. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I am trying to find out what happens in this scenario:


What actually happens in the BACKUP COPIES above? Does Oracle RMAN read the data files each time for each separate copy? Or does it read only once and write as many copies as specified?

share|improve this question
up vote 3 down vote accepted

In case you specify COPIES 2 each block is read once and written two times to backupset copies. The two backupset copies are supposed to be bit-to-bit identical. Both copies have the same backupset key (BS_key) in RMAN. You cannot mix tape and disk copies - either both copies go to DEVICE DISK or both to DEVICE SBT.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.