Sorry for late reply.
> On Tue, Apr 14, 2020 at 09:19:22PM +1200, David Rowley wrote:
>
> I've not yet looked at the latest patch, but I did put some thoughts
> into an email on the other thread that's been discussing UniqueKeys
> [1].
>
> I'm keen to hear thoughts on the plan I mentioned over there. Likely
> it would be best to discuss the specifics of what additional features
> we need to add to UniqueKeys for skip scans over here, but discuss any
> chances which affect both patches over there. We certainly can't have
> two separate implementations of UniqueKeys, so I believe the skip
> scans UniqueKeys patch should most likely be based on the one in [1]
> or some descendant of it.
>
> [1] https://www.postgresql.org/message-id/CAApHDvpx1qED1uLqubcKJ=oHatCMd7pTUKkdq0B72_08nbR3Hw@mail.gmail.com
Yes, I've come to the same conclusion, although I have my concerns about
having such a dependency between patches. Will look at the suggested
patches soon.