Performing Database Point-In-Time Recovery

RMAN can perform recovery of the whole database to a specified past time, SCN, or log sequence number. This type of recovery is sometimes called incomplete recovery because it does not completely use all of the available redo. Incomplete recovery of the whole database is also called database point-in-time recovery (DBPITR).
If you have enabled the collectionof flashback logs, you may be able to use Oracle Flashback Database instead of performing DBPITR. Flashback Database is generally faster and simpler to use, when it is available, because it does not require restoring a past backup. Depending upon your situation, you may also find one of the other Oracle flashback features can meet your data recovery need. See "Oracle Flashback Technology: Overview" for more details about these alternatives before deciding whether to use DBPITR.
DBPITR requires restoring your database from an older backup, then performing media recovery until your specified target time, SCN or log sequence number. Note that because you need your archived redo log files to perform this process, you cannot perform database point-in-time recovery if you have been running your database in NOARCHIVELOG mode.
After database point-in-time recovery, you must open the database with the RESETLOGS option. Using the RESETLOGS option archives the current online redo logs, resets the log sequence to 1, and then gives the online redo logs a new time stamp and SCN. In this way, the database eliminates the possibility of corrupting datafiles by the application of obsolete archived redo logs.
You have to recover all datafiles: you cannot recover some datafiles before the RESETLOGS and others after the RESETLOGS.
The OPEN RESETLOGS operation will fail if a datafile is off-line, unless the datafile went offline normally or is read-only. You can bring files in read-only or offline normal tablespaces online after the RESETLOGS because they do not need any redo.
When performing DBPITR, consider using the SET UNTIL command to set the target time at the beginning of the process, rather than specifying the UNTIL clause on the RESTORE and RECOVER commands individually. SET UNTIL sets the desired time for any subsequent RESTORE, SWITCH, and RECOVER commands in the same RUN job.
Note that if you specify a SET UNTIL command after a RESTORE and before a RECOVER, you may not be able to recover the database to the point in time required because the restored files may already have time stamps more recent than the set time. Hence, it is recommended that you specify the SET UNTIL command before the RESTORE command.