Re: RMAN vs EXP/IMP

"DA Morgan" <damorgan_at_x.washington.edu> wrote in message news:1111415952.514581_at_yasure...
> Mike Cretan wrote:
>
>> Hey, as a developer, I'd pick export every time.... There's nothing
>> worse than having to recover an entire database if you just dropped one
>> little table by mistake... ;-)
>>
>> Mike
>
> Assuming 10g as I see no version number in this post ... I would
> definitely prefer RMAN. To paraphrase you ... "There's nothing worse
> than having to recover an entire table by mistake because you lost one
> little block."
>
> Though in 10g the proper thing to do would just be to flashback to an
> SCN or point-in-time.
>
> In 9i I would still use RMAN because your assumption about a single
> table restore not being possible is not valid.
> --
> Daniel A. Morgan
> University of Washington
> damorgan_at_x.washington.edu
> (replace 'x' with 'u' to respond)

Ok, seriously - I appreciate what you are saying about RMAN, and for a production system, there is no substitute for quick and easy recover with the same power...

However, our (9206) backup regime involves using RMAN for recovery of the database in the event of corruption/failure, PLUS full system exports, for recovery of a schema up to 6 months ago. The RMAN backup file is 18GB, using a total to stored 3 days worth 54GB, and the exports are compressed into a 1.5GB file (yes - tiny DB, I know). We are able to retain exports of every day for the last 2 weeks, plus every fortnight for the last 6 months, on 160 GB disk

So when our accountant comes to me and says, "Oh, by the way I made a bit of a cockup with the year end accounts of a particular ACCPAC company (data stored in one schema) 3 1/2 weeks ago, can you restore it to 4 weeks ago so I can access it" - I say "sure", a couple of minutes later I've got the original schema restored to a different schema that they can access, and they're happy.

If I were to do it all in RMAN, first I'd have to be a dedicated DBA, because if I weren't I wouldn't (and haven't) figured out how to use the obtuse CLI that RMAN provides; next we'd have spent an additional $15K disks or a a high end tape loader because of the extra backup storage requirements; and finally I'd need to create another database somewhere, because I don't want to blow away the rest of production just to restore a single schema. You'll probably start talking about restoring tablespaces to a point in time, but hey if you know how your application sits in the database, then I suggest that a schema is a logical unit to restore, and exp/imp provides greater flexibility and simplicity than RMAN in cases like this.

So if you want my recommendation - do both ;-)

Mike Received on Tue Mar 22 2005 - 16:19:43 CST