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From: Andrei Lepikhov <[email protected]>
To: Attila Soki <[email protected]>
To: Laurenz Albe <[email protected]>
Cc: [email protected]
Subject: Re: unstable query plan on pg 16,17,18
Date: Fri, 27 Feb 2026 16:35:31 +0100
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
References: <[email protected]>
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On 27/2/26 16:00, Attila Soki wrote:
> On 27 Feb 2026, at 09:15, Andrei Lepikhov <[email protected]> wrote:
> I dont know the inner workings of analyze, is that normal that executing 
> analyze on unchanged data can flip the plan? Does analyze select a 
> random set of rows?

Yes, this is completely normal because ANALYZE works in a random way.
You can try using the Join-Order-Benchmark to see how running the 
ANALYZE command can change the execution time of the same query, 
sometimes by as much as ten times.

-- 
regards, Andrei Lepikhov,
pgEdge

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