Re: no archivelog incomplete recovery?

From: Hemant K Chitale <>
Date: Mon, 07 Jul 2008 23:01:30 +0800
Message-Id: <>

The keywords
"how to recover from a lost active online redo log in noarchivelog mode."


As the database is in NOARCHIVELOG, the only way a redo log could be ACTIVE would be if a Checkpoint hasn't been completed. [had the lost online redo log been an Inactive one, you wouldn't have needed to do a Restore AT ALL, provided that you knew what to do !].

The only option is to Restore the last Consistent Backup. IF the Consistent Backup included the Online Redo Logs, then you do not need to RESETLOGS. If , however, the DBA had followed the advice of most "experts" and the documentation and did not backup his Online Redo Logs [in his Consistent Cold Backup of a NoArchiveLog database] you would HAVE to do a RESETLOGS.

(having said that, I guess it should be obvious that I don't agree with most "experts" and the documentation that you should NEVER backup the Online Redo Logs. This is one of the scenarios where a backup of the Online Redo Logs [in a Consistent Cold Backup] would make an OPEN less "uncomfortable" !

But coming back to the scenario provided in your test : Although a RESETLOGS would be adviced, a RECOVER DATABASE wouldn't be needed at all.

    The sequence would be :

  1. Restore Consistent Backup.
  2. Verify if it included Online Redo Logs. If if did not include the Online Redo Logs, go to step e.
  3. STARTUP {ie, the same as STARTUP MOUNT; ALTER DATABASE OPEN (normal)} in sqlplus / as sysdba
  4. exit from sqlplus prompt and get a pay raise

Hemant K Chitale

At 07:57 AM Monday, John Smith wrote:
>I am studying for the OCP, and one of the practice test questions is
>how to recover from a lost active online redo log in noarchivelog
>mode. the answer they give is to restore a consistent backup,
>startup in mount mode, perform a cancel based recovery, and open
>with resetlogs.
>Is that answer correct? I didnt think you could do a recovery if
>you arent in archivelog mode.

Hemant K Chitale

"A 'No' uttered from the deepest conviction is better than a 'Yes' merely uttered to please, or worse, to avoid trouble." Mohandas Gandhi Quotes

Received on Mon Jul 07 2008 - 10:01:30 CDT

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