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Date: Sun, 2 Sep 2018 14:05:11 -0300
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andrew Gierth <andrew@tao11.riddles.org.uk>,
	=?iso-8859-1?Q?Andr=E9_H=E4nsel?= <andre@webkr.de>,
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Subject: Re: Two constraints with the same name not always allowed
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On 2018-Sep-02, Tom Lane wrote:

> This also points up the lack of a suitable unique index on pg_constraint.
> It's sort of difficult to figure out what that should look like given that
> pg_constraint contains two quasi-independent collections of constraints,
> but maybe UNIQUE(conrelid,contypid,conname) would serve given the
> reasonable assumption that exactly one of conrelid and contypid is zero.

Hmm ... c.f. 7eca575d1c28.  Maybe we should split them out?  Are there
reasons to have them together at all?

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services