I also want to add notnullattnums for the UniqueKey stuff as well, by comparing your implementation with mine, I found you didn't consider the NOT NULL generated by filter. After apply your patch:
create table a(a int); explain (costs off) select * from a where a > 3 and a is null; QUERY PLAN ------------------------------------- Seq Scan on a Filter: ((a IS NULL) AND (a > 3)) (2 rows)
The detection of self-inconsistent restrictions already exists in planner.
# set constraint_exclusion to on; SET # explain (costs off) select * from a where a > 3 and a is null; QUERY PLAN -------------------------- Result One-Time Filter: false (2 rows)
