Re: operator exclusion constraints

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Jeff Davis <pgsql@j-davis.com>, pgsql-hackers@postgresql.org
Date: 2009-11-02T11:53:49Z
Lists: pgsql-hackers
On Sun, 2009-11-01 at 18:07 -0500, Tom Lane wrote:
> Simon Riggs <simon@2ndQuadrant.com> writes:
> > The syntax be easier to read if it was stated as a comparison
> > e.g. in the circle example
> >   CHECK ( NOT (NEW.c && c)) USING GIST
> 
> I don't think this is a good idea at all.  NEW is a nonstandard
> Postgres-ism, and introducing it into this syntax doesn't seem very
> future-proof to me.  What's more, the above is not in the least
> analogous to a regular CHECK constraint, because there's some implicit
> notion of "c" ranging over all other rows, which is not what is meant
> by the same column reference in a CHECK constraint.
> 
> I agree that the proposed syntax is a bit awkward, but this isn't
> better.

Agreed. Just looking for readable, future-proof syntax.

-- 
 Simon Riggs           www.2ndQuadrant.com