Re: ENABLE NOVALIDATE behaviour bug

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Wed, 30 Jun 2004 15:14:33 +0100
Message-ID: <018601c45eac$916a38a0$7102a8c0@Primary>

Note in-line

Regards

Jonathan Lewis

http://www.jlcomp.demon.co.uk

http://www.jlcomp.demon.co.uk/faq/ind_faq.html The Co-operative Oracle Users' FAQ

http://www.jlcomp.demon.co.uk/seminar.html Optimising Oracle Seminar - schedule updated May 1st

Original Message ----- From: "Richard Foote" <richard.foote_at_bigpond.com>

I've run tests on 8i and 9i and the CBO is not clever enough to determine such "certainties" with FKs even if there's a check constraint on the parent column(s), such as a check range constraints so that logically a FK value can't exist (I can post some demos if anyone's interested although it's easy enough to play with this oneself).

[JPL] Just as an aside - I've got a test case, though, where a
[JPL] check constraint on one table gets forwarded by transitive
[JPL] closure to become a predicate on a second table - 9.2.0.4

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Received on Wed Jun 30 2004 - 09:13:14 CDT