Hrishi Joshi <[EMAIL PROTECTED]> writes:
> I need to define a Unique index on 3 non-PK fields (composite key) on my
> table in PostgreSQL 8.0.3.
> The problem is, if any of those 3 fields is Null, PostgreSQL allows
> duplicate rows to be inserted.
That is the behavior defined by the SQL standard.
> But I need to know how can I make PostgreSQL throw error on attempt to
> insert second record having same 3 field values, one of them being Null.
You can't. Rethink your data representation, instead. You are misusing
NULL if you think that it represents something unique.
regards, tom lane
---------------------------(end of broadcast)---------------------------
TIP 6: explain analyze is your friend
