Re: Cheap Cheap Database Recovery
Date: Tue, 24 Feb 2009 17:09:56 -0800 (PST)
Message-ID: <71f7a2dc-aad4-4eca-8d4a-47dcfe141884_at_g38g2000yqd.googlegroups.com>
Hi John,
I I do have a valid backup, at 2:30 am. There is no way I can apply future archive logs using a controlfile who does not know anything of the future. You need a controlfile which has information of what archived logs have been created. As I told you before, I tried your approach and try to move forward using the controlfile from the cold backup. It did not work. Unless there is some other commands that I don't know, of course.
This is what I did for trying your theroy:
--untar full backup in second server
--startup mount
--select * from v$recover_log
0 rows returned.............................here it is, the
controlfile sees that its SCN matches the SCN of the datafile
headers...nothing to recover
I don't remember if I try the recover command, but if I did Ican't recall the exact response from the database.
But if you do the same thing with newer control files, you'll get as many rows (from the select statement above) as archive logs have been created since the last backup.....minus the ones that are still in the online redo logs of the production database where the backup controlfile statement was issued.
What is the the recover statement you would apply to advance into the future with a controlfile that is in sync with the datafiles (as in the cold backup case) ?
BTW, Now I know how to consistently recover my database to lets say1 minute ago, using this method....all I need to do is 'alter system switch logfile' n times, where n is the number of groups of my redo log files. That way I am purging all online redo logs, and then 'alter database backup controlfile to 'binary.file' to get the recent controlfile will do the rest of the trick. Once that I do the above I can restore the database in the second server without practically losing data.
Best regards,
Andres
Received on Tue Feb 24 2009 - 19:09:56 CST