On Sat, 2012-09-08 at 12:40 +0000, rikard.pave...@zg.htnet.hr wrote: > The following bug has been logged on the website: > > Bug reference: 7525 > Logged by: Rikard Pavelic > Email address: rikard.pave...@zg.htnet.hr > PostgreSQL version: 9.1.2 > Operating system: Windows 7 > Description: > > Is there a way in Postgres to create a unique constraint with predicate or > an unique index which is deferred? > > Depesz said not yet. > http://www.depesz.com/2009/08/11/waiting-for-8-5-deferrable-uniqueness/
Both features exist. http://www.postgresql.org/docs/9.2/static/sql-createtable.html CREATE TABLE xyz(i int, j int, unique (i) deferrable); To create a unique index with a predicate, do: CREATE UNIQUE INDEX xyz_uniq_idx ON xyz(j) WHERE j > 10; However, it can't both be deferrable and have a predicate. In order to do that, you need to use an exclusion constraint: http://www.postgresql.org/docs/9.2/static/sql-createtable.html#SQL-CREATETABLE-EXCLUDE To make it equivalent to UNIQUE, set all operators to "=", e.g.: CREATE TABLE xyz(i int, exclude (i WITH =) where (i > 10) deferrable); Regards, Jeff Davis -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs
