B&R Control File restore.

[Sureshy]

Hi Friends...

Imagine the folowing scenario over a 5 day period.

Day 1 - Full online database backup
Day 3 - Alter Tablespace TSPACE1 add datafile / Perform full online backup afterwards.
Day 5 - Media Failure, requires restore/recovery for TSPACE 1.

Question..

When the restore/recovery takes place - should the control file backup up on day 1 be used or the control file backup up on day 3 ?

If the control file from day 1 is used.. is the ddl used to create extra datafile included in archive logs thus making the control file current (including added datafile on day 3) at the end of complete recovery.

Thanks

Suresh

[mageri]

Originally posted by Sureshy
Hi Friends...

Imagine the folowing scenario over a 5 day period.

Day 1 - Full online database backup
Day 3 - Alter Tablespace TSPACE1 add datafile / Perform full online backup afterwards.
Day 5 - Media Failure, requires restore/recovery for TSPACE 1.

Question..

When the restore/recovery takes place - should the control file backup up on day 1 be used or the control file backup up on day 3 ?

If the control file from day 1 is used.. is the ddl used to create extra datafile included in archive logs thus making the control file current (including added datafile on day 3) at the end of complete recovery.

Thanks

Suresh

Hi Suresh!

You need not to use a backuped control file. The new datafile is recorded in the actual controlfile. But you have to replace the datafiles of TSPACE1 with the backuped files from day 3 and the archived redologs.

Thanks

[Sureshy]

Hi Mageri..

Thanks for your reply.

Does that mean that when the archived logs are applied from day 1, the ddl will be in them to create the new datafile in day 3's archive logs, also updating the control file ?

Thanks
Suresh

[vinit]

Hi,
The archived logs will be applied from where the point the restore has been done. If you've done a restore from the day 3 , then only the logs from that point will be applied. This means that your restore already contains the datafile for the new tablespace. Only the ddls will have needed to be applied.


Cheers
Vinit

[mageri]

Originally posted by Sureshy
Hi Mageri..

Thanks for your reply.

Does that mean that when the archived logs are applied from day 1, the ddl will be in them to create the new datafile in day 3's archive logs, also updating the control file ?

Thanks
Suresh

You only needs the archived logs since last hot backup, from day 3, for recovery.

[julian]

You only needs the archived logs since last hot backup, from day 3, for recovery.

Some DBAs prefer to keep all archived logs since DB creation (for one reason or another).

[dknight]

Is there any reason to keep archive logs if the backup sets that use them are not also kept?

[vinit]

Hi,
Maybe..if the latest sets of backup are corrupted and you need to go to the one taken before. Comes in handy

Cheers
Vinit

[dknight]

But suppose that 7 (for the sake of discussion) backups are kept.

Archive logfiles applicable to backups earlier than those 7 are worthless and should be deleted.