Message-ID: <8f2a034a-6e32-43f4-92e9-276b15dc0a5f@gmail.com>
Date: Sun, 18 Jan 2026 10:24:56 +0100
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Subject: Re: Slow queries on simple index
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Lillian Berry <lillian@star-ark.net>,
 pgsql-performance@lists.postgresql.org, infra@pluralkit.me
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 <77030.1768684245@sss.pgh.pa.us>
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From: Andrei Lepikhov <lepihov@gmail.com>
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On 17/1/26 22:10, Tom Lane wrote:
> Andrei Lepikhov <lepihov@gmail.com> writes:
>> Hmm, where is the evidence that your query uses theindex? Maybe the
>> generic plan accidentally forces SeqScan?
> 
> Oh ... you're on to something.  I think we all assumed that this was
> an intermittent problem, but if it happens every time, I bet it's a
> datatype mismatch issue.
Yes, index mismatches due to type differences are frequently a pain for 
me in the world of auto-generated queries. Why not spend a few 
additional cycles to check whether a potential cast is possible?
I didn't track what happened in this example, but it would be beneficial 
to let an extension implement such functionality. The prosupport 
machinery attached to an index looks like a promising approach.

-- 
regards, Andrei Lepikhov,
pgEdge