Re: Oracle Cold Backup Shared tablespaces

Howard J. Rogers wrote:
>
> Hi Carol,
>
> Two databases cannot "share" the same tablespace. Do you mean that two
> different data files, each relating to a DATA tablespace in two different
> databases, happen to reside on the same disk, in the same directory? If so,
> that's not a problem (though, as you yourself say, the obscurity of such a
> layout of files might well be!). Prove it to yourself: select name from
> v$datafile in both databases, one at a time, and compare the file path and
> names. No identical filename will appear in both reports. (You can always
> post back here if you happen to have pulled off the impossible! It should
> be enlightening!!)
>
> Recovery using cold backups is straightforward. You won't get verification
> check errors, because the files were copied cold and consistent (assuming
> you do a nice 'shutdown immediate' and not just a shutdown abort, which
> would require the online redo logs to effect recovery).
>
> And yes, you'll be able to restore to a completely different server, and
> completely different directory layouts. The trick there is to get to the
> MOUNT state first, and issue a whole series of "alter database rename file
> 'X' to 'Y'" commands to persuade the controlfile to look in the new
> locations ("Y") and not the old ones ("X"). (Things are rather easier if
> you've got tracefile backups of your controlfiles... then you just edit the
> script and manually alter the paths, blow away the old controlfiles, and run
> the script to create the new ones -with the paths previously edited in the
> script, the new controlfiles will already have the right settings). Of
> course, the new server needs to be configured correctly, first. And there
> are some init.ora settings that would have to be changed first (things like
> 'control_files' and 'background_dump_dest' and 'user_dump_dest' for
> example).
>
> But in prinicple, it's not difficult.
>
> Regards
> HJR
> --
> ----------------------------------------------
> Resources for Oracle: http://www.hjrdba.com
> ===============================
>
> "Carol" <cmcalear_at_pulsion.co.uk> wrote in message
> news:ecbcb718.0203040754.d3daadc_at_posting.google.com...
> > Hi there
> >
> > I am new to oracle and I am trying to get up to speed very quickly.
> > I have recently took over administration of two oracle databases on
> > the same server, these two databases share a temporary and data
> > tablespace, my question is with regards to backup and restore. At the
> > moment the first database is shutdown and the files are copied to a
> > backup directory using a batch file which just copies them using
> > operating system commands, once this is complete the second database
> > is shutdown and the files are copied in the same way. Will I be able
> > to recover both the databases in the event of a failure or will I be
> > told that the temp and data file for one of the databases has failed a
> > verification check? Also the directory structure on this server is
> > obscure, would in the event of failure would I be able to copy these
> > files to a new server and restore the database? The databases are
> > both running in noarchive log mode.
> >
> > Thanks in advance

I don't think that this is the issue here - but you could conceivably "transport" a read-only tablespace to multiple databases on the same machine and not actually move the file at all...You'd then have a "shared tablespace"

Cheers
Connor

-- 
==============================
Connor McDonald

http://www.oracledba.co.uk

"Some days you're the pigeon, some days you're the statue..."