Re: Poor row estimates from planner, stat `most_common_elems` sometimes missing for a text[] column

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Matt Long <matt(at)mattlong(dot)org>
Cc: Mark Frost <FROSTMAR(at)uk(dot)ibm(dot)com>, "pgsql-performance(at)lists(dot)postgresql(dot)org" <pgsql-performance(at)lists(dot)postgresql(dot)org>
Subject: Re: Poor row estimates from planner, stat `most_common_elems` sometimes missing for a text[] column
Date: 2025-09-19 19:23:22
Message-ID: 2157136.1758309802@sss.pgh.pa.us
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Matt Long <matt(at)mattlong(dot)org> writes:
> I finally got around to testing your patch on a realistic data set. In
> short, the patch worked beautifully even with the division by 2 removed. In
> case it's helpful, the full write up of my investigation can be found at
> https://gist.github.com/mattlong/0617bec6e1cf5bc6b70c6c2951901df7

Thank you! I'm now inclined to keep the divisions by 2 (with comment
fixes).

regards, tom lane

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