limits of max, min optimization - Mailing list pgsql-hackers

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?

I need to do manual transformation of query

select max(insert_date) from foo join boo on foo.boo_id = boo.id

where foo.item_id = 100 and boo.is_ok

to

select insert_date from foo join boo on foo.boo_id = boo.id

where foo.item_id = 100 and boo.is_ok order by insert_date desc limit 1;

Regards

Pavel