Re: Using each rel as both outer and inner for JOIN_ANTI

Thanks Tom for the rebase and pushing.  Agreed that we need to add more
testing to cover Parallel Hash Right Anti Join.  I tried one in
join_hash.sql as below

explain (costs off)
select count(*) from simple r right join bigger_than_it_looks s using (id) where r.id is null;
                             QUERY PLAN
---------------------------------------------------------------------
 Aggregate
   ->  Gather
         Workers Planned: 2
         ->  Parallel Hash Right Anti Join
               Hash Cond: (r.id = s.id)
               ->  Parallel Seq Scan on simple r
               ->  Parallel Hash
                     ->  Parallel Seq Scan on bigger_than_it_looks s
(8 rows)

But as Thomas said, maybe we need to wait until that file becomes
faster.

Thanks
Richard