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Subject: Re: issue about information_schema REFERENTIAL_CONSTRAINTS
From: Peter Eisentraut <peter_e@gmx.net>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Alvaro Herrera <alvherre@commandprompt.com>, Fabien COELHO
	<coelho@cri.ensmp.fr>, PostgreSQL Bugs List <pgsql-bugs@postgresql.org>
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Date: Sun, 05 Sep 2010 21:47:43 +0300
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On fre, 2010-09-03 at 13:53 -0400, Tom Lane wrote:
> Alvaro Herrera <alvherre@commandprompt.com> writes:
> > Excerpts from Fabien COELHO's message of vie sep 03 13:39:19 -0400 2010:
> >> I tried to explained that I'm analyzing other people's schemas. I cannot 
> >> ask all other people on the planet to rewrite their schemas, I pick them 
> >> as they are.
> 
> > Maybe you shouldn't be using the information_schema in the first place.
> 
> It would probably be reasonable to put something into chapter 34 of the
> docs pointing out this limitation.  I'm not sure exactly where though.
> Should we invent a "compatibility issues" section in that chapter,
> analogous to the ones we have for individual SQL commands?  Are there
> other issues worth documenting for the information_schema views?

A very similar issue is already documented here:

http://developer.postgresql.org/pgdocs/postgres/infoschema-triggers.html