Re: Switch to image copy and current_scn?

From: Guillermo Alan Bort <cicciuxdba_at_gmail.com>
Date: Wed, 24 Apr 2013 23:13:29 -0300
Message-ID: <CAJ2dSGTec_Gk80erVE-mG5iAEPtX_zcHwghnodWLqX2kqA0f5Q_at_mail.gmail.com>



Image copies are tricky, but if you keep the same controlfile, then if the database opens, it is up to date and consistent. If you have an outdated image copy and a current controlfile and try to open the database, it will give you an error saying that some datafile needs media recovery. Now, as to evidence... I would consider it enough if the archives are all applied and the database opens. You can check whether the archives are applied from a view (I don't remember the name). Or you could do a simple insert on a test table, and then open the database and see if the insert is reflected there...
I think this might be the view I was thinking about: http://docs.oracle.com/cd/B14117_01/server.101/b10755/dynviews_1015.htm

hth
cheers.

Alan.-

On Wed, Apr 24, 2013 at 8:48 PM, Chen Zhou <oracle.unknowns_at_gmail.com>wrote:

> Hi,
> I would like to verify our backup strategy, which uses incrementally
> updated image copies. So in my test I plan to switch the database to its
> image copy, then recover database and open it. However I am not sure what
> is the most convincing evidence that the image copy is the same as the
> original database. I thought of using scn, however, it seems when the
> database is mounted, but not opened, the scn stays as 0. As soon as the
> database is switched over to its copy, recovered and opened, its
> current_scn starts to grow.
> So what is a most convincing way to show that the image copy is at the same
> point as the old database?
> Thanks,
> Chen
>
> --
> http://www.freelists.org/webpage/oracle-l
>
>
>

--
http://www.freelists.org/webpage/oracle-l
Received on Thu Apr 25 2013 - 04:13:29 CEST

Original text of this message