>
> I think it would not work for outer joins if we only check
> exprs_known_equal() for equivalences. If the equi-join conditions
> involving pairs of matching partition keys are outer join quals
> mentioning nonnullable side rels, they would not exist in any EC
> according to the current EC infrastructure. So we still have to look
> through restrictlist.
>
When I wrote that function and even today, EC didn't accommodate outer
join equality conditions. If we can somehow do that,
have_partkey_equi_join() can be completely eliminated.
--
Best Wishes,
Ashutosh Bapat