Suppose you have just added several data files to your database, and you want to ensure that you have a backup of them. You can issue the following command to instruct Oracle to back up data files that have not yet been backed up:
RMAN> backup database not backed up;You can also specify a time range for such files that have not yet been backed up. Say you discover that your backups have not been running for the last several days, and you want to back up everything that hasn’t been backed up within the last 24 hours. The following command backs up all data files that have not been backed up within the last day:
RMAN> backup database not backed up since time='sysdate-1';The prior command is also useful if, for any reason (a power failure in the data center, your backup directory’s becoming full during backups, and so on), your backups aborted. After you have resolved the issue that caused your backup job to fail, you can issue the previous command, and RMAN will back up only the data files that have not been backed up in the specified time period.
