Re: DBA - stuff

Thanks for the tips, might save me some time someday. Can't we get a FAQ (or more appropriately FAP - Frequently Answered Problems), started on these undocumented features/bugs/time savers?

Roald.

-- 

+-------------------------------------------------------+
| R.A. van Geleuken                     roald_at_xs4all.nl |
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| There's no such thing as impossibility, only          |
| extremely low chance                                  |
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Niels Duelund 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)