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Finding the sequence of the last full backup
I have an Oracle database working in archive mode. Could you tell me how to find the sequence of the last full backup?
I have an Oracle database working in archive mode. I know that "to recover DB to the time of failure, all archived log files from the last full backup should be available," so I think that means I can delete all archived log files that have log sequence numbers smaller than the sequence at the time of last backup (Do you understand? What I mean is that all archived log files that were performed before the last backup can be removed to gain space.). So could you tell me how to find the sequence of the last full backup?
You are correct that to recover to a specific point in time, you need a backup and archived redo logs up to that point in time. One of the things that many sites do is keep multiple generations of their backups, just in case the most recent backup isn't good for some reason. If you keep multiple generations of your backups, you'll need all of the archived redo logs that go with it.
You can query V$LOG_HISTORY to know the SCN numbers in a particular archived redo log, along with the time that the archived redo log holds its first SCN. A query similar to the following can help you:
SELECT sequence#,first_change#,TO_CHAR(first_time,'MM/DD/YY HH24:MI:SS') AS time FROM v$log_history;
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