On 2010-05-30 06:55 +0300, Robert Haas wrote: > On Sat, May 29, 2010 at 11:40 PM, Tom Lane <t...@sss.pgh.pa.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 -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers