On 12 July 2011 19:26, Josh Berkus <j...@agliodbs.com> wrote: > On 7/12/11 9:46 AM, Andres Freund wrote: >> Hi, >> >> I guess $subject wasn't implemented because plain unique indexes aren't >> represented in pg_constraint and thus do not have a place to store >> information >> about being deferred? >> Other than that I do not see any special complications in implementing it? > > Um, I thought that deferrable unique constraints were a 9.0 feature, no? >
Yes, but there is no syntax to create a unique constraint on an expression, and hence to create a deferrable unique expression check. However, that doesn't seem like such a serious limitation, because the same functionality can be achieved using an exclusion constraint with the equality operator. Regards, Dean -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers