1) Step1: Shut down the database and perform a whole closed database backup (including control files and redo logs) before you start the incomplete recovery. There are two reasons for this: 1) If your incomplete recovery fails (for example, you recover past the desired point of recovery), you will not be able to apply the redo logs and control files that you have already used for the next recovery. You will need to use the backup of these files. 2) It saves you time if your first attempt fails. If this happens, you can restore the datafiles from the new backup, rather than from a previous backup that needs to have archived logs applied. If you cannot perform a whole backup for some reason, you should at least archive the current redo logs (by issuing the ALTER SYSTEM ARCHIVE LOG CURRENT statement) and back up the control file.
2) Step 2: Restore all datafiles (only datafiles). In order to take your database back in time, you need to restore all the datafiles (not from the backup made in the previous step). In an Oracle database, transaction activities can only be rolled forward to the desired time, not back to that time. If you fail to restore all the datafiles, the database will not be synchronized and cannot be opened.
3) Step 3: Open the database in mount mode.
4) Step 4: Recover the datafiles to the specified time, redo log file, or change number.
In this example, the datafiles are only recovered until ARC_70.ora is applied and then the recovery process is terminated.
5) Step 5: Open the database with the RESETLOGS option. After incomplete recovery, the datafiles have different sequence numbers with the control files and online redo log files. You have to open the database with the RESETLOGS option to synchronize all datafiles. During this process, if a redo log file is missing, it is automatically recreated.
6) Step 6: Perform a whole database backup after successful incomplete recovery.
After you open the database with the RESETLOGS option, all the files are synchronized to the same number. Notice that the RESETLOGS option reset all the files to 1. It is important to perform a whole database backup after a successful incomplete recovery because this is the only valid backup if a recovery is required at a later time.
