LIMIT clause extremely slow

From: "Melzer Kassensysteme" <office(at)melzer-kassen(dot)com>
To: <pgsql-bugs(at)lists(dot)postgresql(dot)org>
Subject: LIMIT clause extremely slow
Date: 2023-11-15 16:46:21
Message-ID: 00f201da17e3$439404c0$cabc0e40$@melzer-kassen.com
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Hi,

I have an issue using a limit clause, f.ex.

SELECT * FROM table WHERE (index1 > 1 OR (index1 = 1 AND index2 > 5)) ORDER
BY index1, index2 LIMIT 1

index1 and index2 are index fields of datatype integer.

This takes some 100 times longer than in Mysql or other databases under same
conditions (and I have to repeat this command very often, so time is adding
up).

I have read in some forums that you can fasten it up by saying

ORDER BY index1 + 0, index2 + 0

The result is better, but still very slow.

Using version 16.1

Thanks for your help and best regards, Florian Melzer

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