Am Donnerstag, 13. Juli 2006 16:40 schrieb Chris Hoover:
> On this table, I have created a unique index on payer_trn03, payer_trn04,
> and expire_timestamp. However, since the expire_timestamp is normally
> null, the unique index does not appear to be working. I have been able to
> enter two identical rows into this table.
This behavior is correct according to the SQL standard, as two null values are
not considered equal.
--
Peter Eisentraut
http://developer.postgresql.org/~petere/