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Restore from hot backup without undo tablespace

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sem

Programmer
Jun 3, 2000
4,709
UA
We're trying to recovere a database. We have hot backup of all datafiles except undo tablespace. Is it possible to get at least anything from such "backup"?
 
Sem,

Yours is a very good question. My initial reaction is that Oracle needs the UNDO tablespace to apply recovery data. Oracle expects to apply REDO data to all tablespaces (including UNDO) from the ARCHIVE and ONLINE REDO log files.

Sem, can you afford the luxury of restoring your backup files and use your current UNDO tablespace file, then issuing a "RECOVER DATABASE" command as a test? If this is a real (versus test) recovery operation, you will be no worse off than you are presently.

Let us know your findings.

[santa]Mufasa
(aka Dave of Sandy, Utah, USA)
@ 17:47 (08Feb05) UTC (aka "GMT" and "Zulu"),
@ 10:47 (08Feb05) Mountain Time

Click here to Donate to Tsunami Relief. 100% of your contributions here go to the victims...0% to administration.
They were "The First-Responder" to the disaster, with relief deliveries arriving before Red Cross and U.S. aid.
 
Dave, I asked that because after RECOVER DATABASE I've got a warning about fuzzy backup, then ora-322, ora-312. Thus I'm still unable to open database. Do you know anything better than switching to undo_management=manual and recreating the file?

Regards, Dima
 
Frankly, Sem, because of these types of "challenges" that UNDO tablespaces present, I do not use them. I find that manual rollback segments are perfectly satisfactory for my needs.

I have no personal experience with your scenario, so I would just be guessing. The problem I anticipate is even if you set your parameter to "undo_management=manual", if your database cannot open because it needs recovery, how can you create manual rollback segments?

[santa]Mufasa
(aka Dave of Sandy, Utah, USA)
@ 18:43 (08Feb05) UTC (aka "GMT" and "Zulu"),
@ 11:43 (08Feb05) Mountain Time

Click here to Donate to Tsunami Relief. 100% of your contributions here go to the victims...0% to administration.
They were "The First-Responder" to the disaster, with relief deliveries arriving before Red Cross and U.S. aid.
 
From a little digging on Metalink and c.d.o it appears you will be unable to open this database, without at the very least a backup of the undo datafiles, because of the reasons Dave first suggested

Alex
 
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