Re: issue about information_schema REFERENTIAL_CONSTRAINTS

On Sun, Sep 12, 2010 at 12:40 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> On Tue, Aug 31, 2010 at 10:46 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>>> We are not going to try to enforce uniqueness.  This has been debated
>>> before, and most people like the current behavior just fine, or at least
>>> better than the alternatives.
>
>> Really?  I 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.  What happens if you say
>> ALTER TABLE .. DROP CONSTRAINT or COMMENT ON CONSTRAINT?  You just
>> pick one at random?
>
> No, because those syntaxes constrain the choice to one single
> constraint.  Perhaps 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 issue.

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

--
Robert Haas
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