Re: Do we still need constraint_exclusion?

Stephen Frost wrote:
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> Simon,
>
> * Simon Riggs (simon(at)2ndQuadrant(dot)com) wrote:
> > I don't really understand this. Who can set up an inherited table
> > structure but can't remember to turn on constraint_exclusion? That is
> > the easiest part of the whole process by a long way. Nobody has this
> > table design by accident, they've all been told how or read the docs.
>
> I can, very easily. It happens whenever we stand up a new server, dump
> our tables into it, create our UNION ALL views, and then try to query
> them. Sure, we've gotten used to "oh, we need to go check and make sure
> constraint_exclusion is on", but it can be annoying, and if we're ever
> handing off our table structures/setups to other people we have to
> remember to tell them "oh, and don't forget to enable
> constraint_exclusion!", etc, etc..

This new change also adds the constraint exclusion overhead only for
inhertance (by default) so it should slightly improve query peformance.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

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