Re: Recover from a deleted System datafile?

Firstly, taking a tablespace offline is not going to work as a means of taking a hot backup. If the tablespace is offline, how hot is it? Er, actually it's stone cold! The idea of hot backups is to take the backup without inconveniencing Users... you take a tablespace offline, and they can't access anything within that tablespace!!

Second, how do you propose to offline the system tablespace? You can't. Therefore, it can *never* be backed up like this.

What you need to do is alter tablespace blah begin backup; -which is quite a different thing.

Your second mistake is to 'recover until cancel'. What you were attempting was a complete recovery. The 'until cancel' command is used with incomplete recoveries. And incomplete recoveries require you to restore *all* data files, not just one.

Your third mistake is to clear out archives too aggressively. There should be at least a day or two's worth of archives on your disk, if you are backing up nightly. Anything else is just trusting to luck.

Check out my site, the books link, and read the backup and recovery document there. It may help.

Regards
HJR

--
Resources for Oracle: http://www.hjrdba.com
===============================


"Greg Akins" <gakins_at_gatewayhealthplan.com> wrote in message
news:cf62a659.0112040630.6f40fc4_at_posting.google.com...


> Hello,

>

> I just started developing a backup/recovery routine.  I'm pretty new

> to this so forgive my stupid mistakes.

>

> The backup is a hot backup.  I take tablespaces offline, copy them and

> put them back online.  I keep copies of all the archive logs from

> start of backup up until current.

>

> Testing a deleted System datafile.

>

> I delete the datafile

> Try to start database <bombs!>

> Copy the backup system datafile and start mount.

> When I issue $svrmgr> recover database until cancel ;

> recover starts asking for archive logs up until '3017' which causes

> the recovery to fail because that archive log was never created.  It's

> not in the backup area, or the current log destination.

>

> What am I doing wrong here?

>

> -greg