From: Tom Lane <tgl@sss.pgh.pa.us>
To: "ldh@laurent-hasson.com" <ldh@laurent-hasson.com>
cc: Andrew Dunstan <andrew@dunslane.net>,
 Justin Pryzby <pryzby@telsasoft.com>,
        Ranier Vilela <ranier.vf@gmail.com>,
        "pgsql-performance@postgresql.org" <pgsql-performance@postgresql.org>
Subject: Re: Big Performance drop of Exceptions in UDFs between V11.2 and 13.4
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Comments: In-reply-to "ldh@laurent-hasson.com" <ldh@laurent-hasson.com>
	message dated "Sat, 28 Aug 2021 18:27:27 -0000"
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Date: Sat, 28 Aug 2021 15:50:43 -0400
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Precedence: bulk

"ldh@laurent-hasson.com" <ldh@laurent-hasson.com> writes:
> SET lc_messages =3D 'C';
> show lc_messages; --> OK 'C'

> explain (analyze,buffers,COSTS,TIMING) =

> select MAX(toFloat(b, null)) as "b" from sampletest
> ...
> Execution Time: 175.600 ms

> explain (analyze,buffers,COSTS,TIMING) =

> select MAX(toFloat(a, null)) as "a" from sampletest
> ...
> Execution Time: 88031.585 ms

> Doesn't seem to make a difference unless I misunderstood what you were a=
sking for regarding the locale?

Hmm.  This suggests that whatever effect Andrew found with NLS
is actually not the explanation for your problem.  So I'm even
more confused than before.

			regards, tom lane