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I've just realised that my comments have a fatal flaw - when you start a parallel DML, the locking your session does should make it impossible for another session do an update that causes the implicit restart. (Maybe it's broken in your version, or for the merge command, I've only been testing with the ordinary update command in the past).
Which version of Oracle are you on, 9.0. or 9.2 ?
Are you updating a partitioned table ?
And you could you tell us what TX, TM and PS
locks appear in v$lock when you run the update.
(If you have a high degree of parallelism, you only
need list the locks from one of the slave SIDs).
-- Regards Jonathan Lewis http://www.jlcomp.demon.co.uk The educated person is not the person who can answer the questions, but the person who can question the answers -- T. Schick Jr Next public appearances: March 2004 Hotsos Symposium - Keynote March 2004 Charlotte NC - OUG Tutorial April 2004 Iceland One-day tutorials: http://www.jlcomp.demon.co.uk/tutorial.html Three-day seminar: see http://www.jlcomp.demon.co.uk/seminar.html ____UK___February The Co-operative Oracle Users' FAQ http://www.jlcomp.demon.co.uk/faq/ind_faq.html "Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in message news:btj5b8$6d7$1$8300dec7_at_news.demon.co.uk...Received on Thu Jan 08 2004 - 10:40:29 CST
>
> I haven't tested in parallel yet, so may be
> wrong, but I think what you're seeing is
> Oracle trying to do a consistent update.
>
> Consider the scenario:
> 4 rows in table with value 'X'
> Session 1 does:
> update table set 'X' to 'Y';
>
> Session 2 manages to do
> update table 'X' to 'Y' in one row;
> commit;
>
> But session 2 does it's commit BEFORE
> session 1 gets to that one row.
>