<wumpus@xxxxxxx> writes: > , unique ( a_id , ( case when actual then 0 else id end ) ) > Why can i not define the unique constraint in the > create table? The syntax for a unique constraint in CREATE TABLE is defined by the SQL standard, and it doesn't include expressions. More than the syntax, a unique constraint also ought to show up in the information_schema views, and those don't have the ability to handle expressions. So we have the capability, but it's only available via CREATE INDEX which is outside the standard. regards, tom lane -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
