Re: Academic question: How to recover through a gap of archived redol ogs with data loss?
Date: Thu, 6 Aug 2009 09:39:11 -0700 (PDT)
The advice I would provide is DO NOT LOOSE LOG FILES. There is no magic bullet here. You loose a log file, then you can't restore beyond that log file. It's good you are thinking of this now rather than after the failure. Way to many times have I found that a DBA did not consider a specific recovery situation, only to be faced with that situation. Oracle is what it is, works like it works. A bike won't fly, your typical bowling ball won't float, and Oracle won't recover beyond a missing log file. One can wish it would be so, but it isn't.
One nasty alternative is mining the remaining redo logs, generating the resulting DDL and then trying to run it into your database. The level of nastiness that this solution involves is perhaps similar to swimming through the sludge at your local water treatment plant in hopes of finding your shiny new wedding ring your spouse just bought you. It would be far better to make sure you don't loose the ring instead.
Robert G. Freeman
Oracle Database 11g RMAN Backup and Recovery (Oracle Press) - ON IT'S WAY SOON! OCP: Oracle Database 11g Administrator Certified Professional Study Guide (Sybex) Oracle Database 11g New Features (Oracle Press) Portable DBA: Oracle (Oracle Press)
Oracle Database 10g New Features (Oracle Press) Oracle9i RMAN Backup and Recovery (Oracle Press) Oracle9i New Features (Oracle Press)
Other various titles out of print now... Blog: http://robertgfreeman.blogspot.com The LDS Church is looking for DBA's. You do have to be a Church member in good standing. A lot of kind people write me, concerned I may be breaking the law by saying you have to be a Church member. It's legal I promise! :-) http://pages.sssnet.com/messndal/church/parachurch.pdf
- Original Message ---- From: Martin Klier <usn_at_usn-it.de> To: oracle-l <oracle-l_at_freelists.org> Sent: Thursday, August 6, 2009 10:24:09 AM Subject: Academic question: How to recover through a gap of archived redol ogs with data loss?
I know it's unsecure, unsupported and ugly. But given this situation:
I need a recovery of a tablespace, all archivelogs are there, bu I miss one from last night. I want to do a "complete" recovery.
The log that's missing is out of a low activity period, and I am ready to acceppt slight data corruption, and I will set up the DB as a new afterwards, but I need the data from this morning.
What can one desperate DBA do?
To make it clear: I don't have this situation at the moment, but someday this may change, and I would prefer to test this stress situation in peacetime (now).
Any hints, advice, procedures?
Thanks a lot
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