UNTIL TIME problem

Question

Hi, I'm starting to use Rman environment for the implementation of our Database backup strategy. But I have one problem of missundestanding concepts. Can somebody explain me how does work the UNTIL TIME option please?.
My problem is with the following rman script:
RUN {
RECOVER COPY OF DATABASE WITH TAG 'incr_update' UNTIL TIME 'SYSDATE - 7';
BACKUP INCREMENTAL LEVEL 1 FOR RECOVER OF COPY WITH TAG 'incr_update' DATABASE PLUS ARCHIVELOG;
In detail, the Rman documentation say that it will implement "Incrementally Updated Backup" with a recovery windows of one week (7 days). But when I execute this example I always get a problem because "SYSDATE - 7" is before the current SCN date. This example is planned to be exectued daily and the update of backup is supposed to occurs the first day of the next week (I mean 8 days after).
So, Is there a error with that part?, does that part must to be corrected with something like SYSDATE + 7?, but if I run this script daily, with SYSDATE + 7, the script never will gets this date, right?.
Please any help and advices regarding this lack of knowledge from me, will be apreciated.
Thanks in advance.
HayrolR
Edited by: HayrolR on Aug 24, 2009 3:07 PM

Answer 1

Use the following until 7th day after the RESETLOGS date and then use your original script.
RUN {
RECOVER COPY OF DATABASE WITH TAG 'incr_update' UNTIL TIME 'SYSDATE';
BACKUP INCREMENTAL LEVEL 1 FOR RECOVER OF COPY WITH TAG 'incr_update' DATABASE PLUS ARCHIVELOG;
}or simply do conventional incremental backups to maintain your retention period and the 7th day after the RESETLOGS date, start using your original script.