Re: ORA-01555; does update/select sequence matter?

John wrote:

>Hi group,
>
>Sanity check.
>1. There is no way to assign a rollback segment to a 'session', right?
>2. It does not matter whether update or select comes first, ORA-01555
>can potentially happen, rihgt?
>
>Thanks.
>
>
>John
>
>

1. Correct
2. Correct ... though as Howard says knowing which came first in a specific situation is not possible;
or at least very difficult and not worth doing.

If on 8i make sure all rollback segments are the same size and increase that size to handle the
largest possible transaction.

If on 9i use an UNDO tablespace rather than rollback segments and increase the UNDO
retention time for longer than your longest running transaction.

-- 
Daniel Morgan
http://www.outreach.washington.edu/ext/certificates/oad/oad_crs.asp
http://www.outreach.washington.edu/ext/certificates/aoa/aoa_crs.asp
damorgan_at_x.washington.edu
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