On Thu, Dec 22, 2022 at 9:50 AM Tom Lane <t...@sss.pgh.pa.us> wrote: > Andrey Lepikhov <a.lepik...@postgrespro.ru> writes: > > Superficial study revealed possibly unnecessary operations that could be > > avoided: > > 1. Walking across a query by calling substitute_phv_relids() even if > > lastPHId shows that no one phv is presented. > > Yeah, we could do that, and it'd help some.
I noticed we also check 'parse->hasSubLinks' when we fix PHVs and AppendRelInfos in pull_up_simple_subquery. I'm not sure why we have this check. It seems not necessary. In remove_result_refs, I don't think we need to check 'lastPHId' again before calling substitute_phv_relids, since it has been checked a few lines earlier. Thanks Richard
