This threw me for a loop. Is this my fault, or a
problem in postgres?
I have a table with the following:
"eg_vehicle_event_pkey" PRIMARY KEY, btree (event_id)
"no_duplicate_events" UNIQUE, btree (thing, other_thing,
"timestamp", number, other_number)
The "no_duplicate_events" constraint works fine, but if I insert records
where
"other_thing" is null, they all go in without complaint. I can insert as
many duplicates as I want.
I had expected two records, identical in all respects including the
null value, to be rejected by the constraint.
This is with:
PostgreSQL 7.4.1 on i686-pc-linux-gnu, compiled by GCC gcc (GCC) 3.2.3
20030502 (Red Hat Linux 3.2.3-20)