On Fri, 3 Oct 2025 at 02:55, Mingli Zhang <[email protected]> wrote: > It seems that the optimization for `UNION ALL` is already implemented in the > patch: it removes empty sub-paths and preserves the remaining ones. > Should we add a test case to formally validate this behavior like Union cases?
If I were to do that, I'd have to come up with something that's flatten_simple_union_all() proof. Maybe something like varying types in the targetlist. I think it's probably not really worthwhile since it's not testing any new code that is not already being tested by the tests that I did add. David
