On Sat, Mar 27, 2021 at 11:44 AM Andy Fan <zhihui.fan1...@gmail.com> wrote: > > > > On Sat, Mar 27, 2021 at 3:07 AM Dmitry Dolgov <9erthali...@gmail.com> wrote: >> >> > On Sat, Feb 20, 2021 at 10:25:59AM +0800, Andy Fan wrote: >> > >> > The attached is a UnqiueKey with EquivalenceClass patch, I just complete >> > the >> > single relation part and may have bugs. I just attached it here for design >> > review only. and the not-null-attrs is just v1 which we can continue >> > discussing on the original thread[2]. >> >> Thanks for the patch. After a short look through it I'm a bit confused >> and wanted to clarify, now uniquekeys list could contain both Expr and >> EquivalenceClass? > > > Yes, That's because I don't want to create a new EquivalenceClass (which > would make the PlannerInfo->eq_classes longer) if we don't have > one , then I just used one Expr instead for this case. > However during the > test, I found some EquivalenceClass with only 1 EquivalenceMember > unexpectedly. >
Pathkeys may induce single member ECs. Why UniqueKeys are an exception? -- Best Wishes, Ashutosh Bapat
