Dave Smith <dave(dot)smith(at)candata(dot)com> writes:
> I am trying to add a unique constraint on a column that can be null. The
> documentation states that null is treated as non equal values but I want
> them to be equal. Is there another way of doing this other than writing
> a before insert trigger?
UNIQUE constraints on NULLable columns work fine. It's not clear from
the above what you're looking for.
Are you really saying that you want 'NULL = NULL' to return 't'?
-Doug