Re: CBO & disabled foreign keys

From: Matthias Hoys <idmwarpzone_NOSPAM__at_yahoo.com>
Date: Thu, 17 Mar 2005 20:40:10 +0100
Message-ID: <4239dd1b$0$28062$ba620e4c@news.skynet.be>

"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in message news:d1ab1v$62f$1_at_hercules.btinternet.com...
>
> The optimizer can make use of them
> if they are marked as 'RELY'.
>
> It also helps if they columns are also
> NOT NULL - if it's true, or course -
> as this gives the optimizer more scope
> for transforming queries.
>
> --
> Regards
>
> Jonathan Lewis
>
> http://www.jlcomp.demon.co.uk/faq/ind_faq.html
> The Co-operative Oracle Users' FAQ
>
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>
>

Is there a difference between fk constraints which have the status "RELY", and those that are "DISABLED NOVALIDATE" ?

Matthias Received on Thu Mar 17 2005 - 13:40:10 CST