Re: Export as Daily Backup

From: David Van Zandt <dvanzandt_at_iquest.net>
Date: Fri, 17 Sep 1999 10:01:48 -0500
Message-ID: <37E257DC.FB5A085@iquest.net>

Time to muddy the waters, if I may. Keith is mostly correct, with (IMO) the timing issue due to the reconstruction of indexes (rather than rebuilding them after the rows, etc., are done). You'll find some performance gains as well if the data is exported compressed (defragged). You also don't mention if you're choosing to do full, incremental, or cumulative exports.

Nor did you mention if you're in archivelog mode or not. Nor, are you exporting with consistentcy turned on. In such cases, your export is not going to include the flags Oracle needs to rebuild your data to a consistent point in time. You may work around this if you close the instance, and do a mount exclusive during the backup, but for that trouble why not do a hot backup? EBU or RMAN are not that difficult to use, and very, very much worth the effort the first time you need to rush a production recovery.

By the way, have you tested your recovery procedure? What happens if you get a media failure on your tape? Single points of failure are things we learn to avoid wherever we can...

Food for thought....

---

Joe F wrote:
>
> Thanks for a clear and concise answer to my question.
>
> Joe
> ---------------------------------------
> Keith Midkiff wrote in message <37E1A352.EF9609CA_at_mail.msy.bellsouth.net>...
> >Exports are one of the oldest and easiest backup methods. Exports have
> been
> >known to fail, but this is rare. You will experience problems only with
> large
> >databases. Recovery using import is a lot longer than backup with export.
> Time
> >required to recover using an export file can easily exceed acceptable
> >allowances. Consider carefully before using as your only backup/recovery.
> And
> >before I ramble on more ... No you don't have to backup control files with
> a
> >full database export.
> >
> >Joe F wrote:
> >
Received on Fri Sep 17 1999 - 10:01:48 CDT