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Re: Rollback extents

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Tue, 2 Jul 2002 21:06:47 +0100
Message-ID: <1025641283.7218.0.nnrp-12.9e984b29@news.demon.co.uk>

Good point -

Although Oracle uses various optimisations for array inserts and "insert as select" - the rollback generated for inserts should be abouit 80 to 100 bytes per row (without indexes) with the same again, plus the length of each index entry, for each index.

To get 800 bytes per row, you would have to have around 8 indexes on the table - and then rig things so that Oracle didn't pack multiple data/index block changes into a single rollback record.

--
Jonathan Lewis
http://www.jlcomp.demon.co.uk

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D.Y. wrote in message ...

>
>When your SQL statement fails everything will be rolled back. How do you
>know you only inserted 200000 rows? This number doesn't explain the fact
that
>you used 160MB undo space.
>
Received on Tue Jul 02 2002 - 15:06:47 CDT

Original text of this message

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