On Wed, 8 May 2024 at 10:40, Tom Lane <t...@sss.pgh.pa.us> wrote: > > David Rowley <dgrowle...@gmail.com> writes: > > We could make the policy copy-on-modify. If you put bms_copy around > > the bms_del_member() calls in remove_rel_from_query(), does it pass > > then? > > Didn't test, but that route seems awfully invasive and fragile: how > will we find all the places to modify, or ensure that the policy > is followed by future patches?
REALLOCATE_BITMAPSETS was invented for this and IMO, it found exactly the problem it was invented to find. Copy-on-modify is our policy for node mutation. Why is it ok there but awfully fragile here? David
