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Date: Fri, 6 Mar 2026 10:05:55 +0100
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Subject: Re: Planner join order regression from PG 15 to PG 16+: 70ms ->
 1440ms (self-contained reproducer included)
To: Mauro Gatti <mauro.gt70@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-performance@lists.postgresql.org
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From: Andrei Lepikhov <lepihov@gmail.com>
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On 6/3/26 09:24, Mauro Gatti wrote:
> In any case, I don’t think there are other workable solutions without 
> changing the code.
The gist of the issue is hidden [anti]correlations between columns.
I like the idea of grouping columns into a custom type when an object in 
the data model is defined by several properties. This approach could 
help reduce the number of clauses, hide correlations within an object, 
and enable the use of histogram statistics.

I'm not sure if this idea is ready to use yet, or if Postgres has 
everything needed to make it work well - just note.

-- 
regards, Andrei Lepikhov,
pgEdge