| RECOVERY TYPE || WHEN TO USE || TYPICAL SITUATIONS || PREVENTION |
| TIME-BASED || A specific point in time is known ||
- Bad data was committed to the database; or
- Important data was dropped. To minimize the data loss and recovery time, the DBA should be notified immediately after the user error occurs.
- You know the approximate time when a non-mirrored online redo log becomes corrupt.
- Multiplex online redo logs
- Test programs, security, and procedures
| CANCEL-BASED || A specific archived redo log file is known ||
- Your current redo log file or group is lost or corrupt and you cannot use it for recovery.
- You lost archived logs needed for recovery.
- Mirror online redo logs
- Make frequent backups and duplex the archived log files.
| CHANGE-BASED || A specific SCN is known || |
- You are recovering a database in a distributed environment.
| N/A |
| BACKUP CONTROL FILE || Complete Loss of the control file || |
- You lose all the current control files. You cannot recreate the control file, but you have the backup of the older control file.
- There is a need to restore the database to a certain point in time with a structure different from the current one.
- Mirror the control file onto a different disk
- Keep a current text version of the control file by issuing the
ALTER DATABASE BACKUP CONTROLFILE TO TRACE; statement.