Re: DBA - stuff
Date: 1996/04/26
Message-ID: <4lqtab$snt_at_inet-nntp-gw-1.us.oracle.com>#1/1
David g <david_ng_at_mindlink.bc.ca> wrote:
>chicnorm_at_inforamp.net (Norm LeBlanc) wrote:
>>Niels Duelund (duelund_at_inet.uni-c.dk) wrote:
>>: Hi out there
>>:
>>: I am managing some databases 10GB+ and this weekend I encountered
>>: some problems AND ANSWERS when reorganizing.
>>:
>>: 1) Avoiding pending rollback
>>: The import failed (lack of rollback) and the database started to
>>: rollback the whole lot. I did not want to wait the 9 hours it would
>>: take, and fortunately i got a hint.
>>:
>>: In init.ora the line:
>>:
>>: _corrupted_rollback_segments (rbs_01, rbs_02, ...)
>>:
>>: did the job. I was able to shutdown (abort) and startup
>>: without rolling back.
>>:
>>: 2) Disabling rollback !
>>: The parameter
>>: _disable_logging = TRUE
>>: results in NO ROLLBACK written at all. It improved performace
>>: a lot (same amount af time as export) and
>>: my rollback segments were not used at all.
>>:
>>: Be careful, since theese are UNSUPPORTED features. Also the safety
>>: you are used to have IS NOT THERE when specifying these parameters.
>>:
>>:
>>: If you know other unsupported parameters please inform me, since
>>: I often (as a consultant) need stuff to "save me on a late night".
>>:
>>:
>>: Niels Duelund (Duelund Data, Denmark)
>>
>>You could also use the COMMIT=Y option in the import parameters.
>>
>What it does is to coomit the import data without using rollback
>segment. As a result, the import process will be faster and there is
>no need of big rollback segment.
>David Ng
But be very careful with this parameter (_disable_logging). If your machine crashes (power loss, etc) you will lose your ENTIRE database, not just the imported information. Use with care.
I would suggest commit=y. You do not need a big rollback segment when using
this.
Thomas Kyte
tkyte_at_us.oracle.com
Oracle Government
opinions and statements are mine and do not necessarily reflect the opinions of Oracle Corporation. Received on Fri Apr 26 1996 - 00:00:00 CEST