Re: Is there any hope of geting a datafile in RECOVER mode backe?

Stan Brown wrote:

> In <3F78774F.BE618C98_at_remove_spam.peasland.com> Brian Peasland
> <dba_at_remove_spam.peasland.com> writes:
>

>>When you restore the datafile, do recovery UNTIL CANCEL as TurkBear
>>indicated. You can reply CANCEL immediately if you wish, or you can roll
>>forward through as many archived redo logs you have until the first one
>>your are missing.

Stan, you can keep starting new threads until the cows come home. But it isn't going to help you much more than you've been helped already because the fundmental issue here is that you don't know how to do recoveries or what the principles are, and you've been 'having a go' for several days, and who therefore knows what state that database is in?

Your datafile 10 is in recover mode. It can't be brought online until it has been recovered. You are missing archives. You can't do a complete recovery if your are missing archive logs. Catch 22.

But there really isn't a mystery about this. I've pointed you to a link to my paper that goes through every one of these scenarios so that you could work it out for yourself, but the principles are easy to state. If you are contemplating an incomplete recovery because of the missing archives, then restore every single datafile, and do a 'recover database until cancel', then an open resetlogs.

If your controlfile has been buggered to death by your previous recovery efforts, then that becomes restore every single datafile and the controlfile and do a 'recover database until cancel using backup controlfile', then an open resetlogs.

If you simply want to know how to get the database opened when datafile 10 is screwed, but you are missing archives that would allow it to be recovered, but you don't want to do an incomplete recovery because of the loss of data elsewhere in the database that that implies, then take datafile 10 offline: alter database datafile 10 offline drop, followed by alter database open (if it will go to that stage).

But you've been stuffing the database around for several days now, so I doubt that merely offlining the offending file is actually going to help you (though it is a matter of moments to try it and see).

I'm not getting at you having made mistakes, since you've freely admitted that this is all new to you. But you keep posting individual questions, such as the one that heads this thread. And your scenario is actually nothing to do with the questions you're asking. It's bigger than a single question here or there. The scenario is actually that a database wasn't backed up properly (or so I seem to remember from another of your posts), is missing some archivelogs, and has had several failed recovery attempts made on it with no backup taken before those recovery attempts were made.

If you'd said all of that in this post, the replies from others would have been rather different, I expect. And generally along the lines of 'you're stuffed. Contact Oracle Support. Be prepared to pay major sums of money to have Oracle extract what data they can from your datafiles.'

The questions I'd ask you before proceeding further are:

1. Do you have any valid backups taken before this disaster began
2. Are those backups hot or cold
3. Precisely which archives are missing
4. If you have a precious good backup when the database was functional, and you restore its datafiles and controlfile, what happens when you try starting that restored database up. What, precisely, are the error messages you get? And what are the outputs from v$backup and v$recover_file?
5. Have you read the Backup and Recovery paper at www.geocities.com/lydian_third/books

Recovery, if it is possible at all, is almost certainly going to consist of going back to your last known good backup if you have one and recovering until the last known archivelog. It's easy when it's described like that, but you have got to know, just roughly, what you are doing.

Regards
HJR Received on Mon Sep 29 2003 - 15:01:27 CDT