Re: [PATCH] ANALYZE: hash-accelerate MCV tracking for equality-only types - Mailing list pgsql-hackers

From John Naylor
Subject Re: [PATCH] ANALYZE: hash-accelerate MCV tracking for equality-only types
Date
Msg-id CANWCAZbzqpMtByniN7Vzrki56X0MuGCvJqP=aqvqxEgJ4VWdCw@mail.gmail.com
Whole thread Raw
In response to Re: [PATCH] ANALYZE: hash-accelerate MCV tracking for equality-only types  (Chengpeng Yan <chengpeng_yan@outlook.com>)
List pgsql-hackers
On Tue, Feb 3, 2026 at 11:33 AM Chengpeng Yan <chengpeng_yan@outlook.com> wrote:
> That said, if other community members would prefer the simpler one-step
> update for readability, I’m happy to switch.

To evaluate that, it would be easier if the patch were split into two
commits, one with the simple step approach, and one that changes to
the other approach.

Also, we have some places that switch from e.g. an array to a hash
table once a collection gets above a certain threshold. In this case,
however, having less than 100 stat target is unheard of, in my
experience. It's only a tiny amount of code, but it doesn't seem worth
special-casing. Others may have a different opinion, and I'm not sure
we don't already have this behavior elsewhere.

--
John Naylor
Amazon Web Services



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