On 2022-Jul-18, Pavel Stehule wrote:
> Hi
>
> I am trying to fix one slow query, and found that optimization of min, max
> functions is possible only when there is no JOIN in the query.
>
> Is it true?
See preprocess_minmax_aggregates() in
src/backend/optimizer/plan/planagg.c
> select max(insert_date) from foo join boo on foo.boo_id = boo.id
> where foo.item_id = 100 and boo.is_ok
Maybe it is possible to hack that code so that this case can be handled
better.
--
Álvaro Herrera Breisgau, Deutschland — https://www.EnterpriseDB.com/