Hi, David Rowley <[email protected]>于2025年10月2日 周四20:09写道：
> On Thu, 2 Oct 2025 at 16:21, Tom Lane <[email protected]> wrote: > > I'm wondering if it could be shortened a great deal by > > handling left-input-dummy and EXCEPT-ALL-with-right-input-dummy > > but leaving the EXCEPT-with-right-input-dummy case unimproved. > > Good idea. Less code and still get to keep the one that did well in > the benchmark. See attached. > > I ended up splitting the patch in two. 0001 for UNION only, then 0002 > for the INTERSECT and EXCEPT. > > David 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?
