On 2010-05-30 06:55 +0300, Robert Haas wrote:
> On Sat, May 29, 2010 at 11:40 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> Yes, I've seen Jeff's example.  It's a cute hack but somehow I doubt
>> that there is going to be a land rush to implement such things.
>> Can you point to any pre-existing example where anyone actually asked
>> for the ability to do that?
> 
> I've often wished for the ability to constrain a tale to hold just one
> row, so I don't find that use case implausible at all.

As I pointed out in
http://archives.postgresql.org/pgsql-hackers/2010-05/msg01177.php , you
can already do that.

Having said that, I also think that supporting <> in exclusion
constraints would be useful.  I can't come up with a real-world use case
right now though.


Regards,
Marko Tiikkaja

In response to

• Re: small exclusion constraints patch at 2010-05-30 03:55:02 from Robert Haas

Responses

• Re: small exclusion constraints patch at 2010-05-30 14:01:46 from Tom Lane

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