On Fri, Nov 29, 2024 at 5:20 PM David Rowley <dgrowle...@gmail.com> wrote: > > The reason I don't think is possible is that we have no infrastructure > that allows us to tag functions or operators so that non-null input(s) > mean non-null outputs. We only have strict, which means null input > means null output. That's the opposite of what we'd need. It might > only be possible with a NULLS NOT DISTINCT index. > Thank you for pointing out "non-null input(s) mean non-null outputs" . I didn't think about it at all.
regarding v10. you placed remove_useless_groupby_columns right after add_base_rels_to_query makes so much sense. so we can be safely use cached RelOptInfo->indexlist, RelOptInfo->notnullattnums overall it didn't find any issue.
