Re: Bug #795: null resulting from left join corrupts select

pgsql-bugs@postgresql.org writes:
> select
>  *
> from
>  test1 left join test2 on (test1.test1_id = test2.test1_id)
> where
>  test1.test1_id = test2.test1_id;

Hm.  I think what is happening is that the planner is (mistakenly)
deciding that the where-clause and on-clause are equivalent, and
so dropping the second one ...

            regards, tom lane