Re: issue about information_schema REFERENTIAL_CONSTRAINTS

On Sun, Sep 12, 2010 at 12:40 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> On Tue, Aug 31, 2010 at 10:46 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> We are not going to try to enforce uniqueness. =A0This has been debated
>>> before, and most people like the current behavior just fine, or at least
>>> better than the alternatives.
>
>> Really? =A0I thought the issue was that no one had figured out how to do
>> it, or that no one had written the patch, not that anyone thought the
>> current behavior was particularly desirable. =A0What happens if you say
>> ALTER TABLE .. DROP CONSTRAINT or COMMENT ON CONSTRAINT? =A0You just
>> pick one at random?
>
> No, because those syntaxes constrain the choice to one single
> constraint. =A0Perhaps if the SQL committee had designed 'em,
> there'd be an issue; but they are Postgres-isms.

Hrm.  I was thinking of this old thread, but maybe that's not the same issu=
e.

http://archives.postgresql.org/pgsql-hackers/2008-10/msg00256.php

--=20
Robert Haas
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