Hi, On 2023-03-01 14:10:07 +0530, Amit Kapila wrote: > On Wed, Mar 1, 2023 at 12:09 AM Andres Freund <and...@anarazel.de> wrote: > > > > > I see this as a way to provide this feature for users but I would > > > prefer to proceed with this if we can get some more buy-in from senior > > > community members (at least one more committer) and some user(s) if > > > possible. So, I once again request others to chime in and share their > > > opinion. > > > > I'd prefer not having an option, because we figure out the cause of the > > performance regression (reducing it to be small enough to not care). After > > that an option defaulting to using indexes. > > > > Sure, if we can reduce regression to be small enough then we don't > need to keep the default as false, otherwise, also, we can consider it > to keep an option defaulting to using indexes depending on the > investigation for regression. Anyway, the main concern was whether it > is okay to have an option for this which I think we have an agreement > on, now I will continue my review.
I think even as-is it's reasonable to just use it. The sequential scan approach is O(N^2), which, uh, is not good. And having an index over thousands of non-differing values will generally perform badly, not just in this context. Greetings, Andres Freund