Re: foreign key references on view DUH...

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Wed, 27 Mar 2002 18:23:32 -0000
Message-ID: <1017254487.14306.2.nnrp-14.9e984b29@news.demon.co.uk>

Surprisingly, Connor wasn't being subtley humourous, you really can add constraints to views in Oracle 9. Though possibly they also have to have the RELY option as well.

The purpose is allow Oracle to be as well informed as possible about data relationships when optimising - in this case I think the aim is particularly to allow Oracle the maximum chance of recognising a few extra possibilities for query rewrite.

I think there is an example in the Perf Guide 9.0.1, but I can't recall the details off-hand.

--
Jonathan Lewis
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TurkBear wrote in message ...


>As my preceding post will indicate, my appreciation for Connor's subtle

humor is impaired early ( for me) in the AM...


>

>

>Connor McDonald <connor_mcdonald_at_yahoo.com> wrote:

>

>

>>I haven't checked them out, but rumour has it that you can add

>>constraints to view in 9i (but I think they have to be DISABLED

>>NOVALIDATE)

>>

Received on Wed Mar 27 2002 - 12:23:32 CST