（248）（题目不完整）You want the ability to recovery any time within the last seven days and therefore you configured the recovery window retention policy using the command:

RMAN> CONFIGURE RETENTION POLICY TO RECOVFRY WINDOW OF 7 DAYS;

After configuring the recovery window, you performed the database backup as follows:

A. Backup RB1 at log sequence number 12871 on 5th Jan

B. Backup RB2 at log sequence number 15622 on 12th Jan

C. Backup RB3 at log sequence 16721 on 15th Jan

D. On 20th Jan when the log sequence number was 18112 you realize that there is a need to a point in time at the beginning of the recovery window.

    You have all archived redo log files to date.

答案：（D）