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Re: Avoid is possible a expensive function call (src/backend/utils/adt/varlena.c) - Mailing list pgsql-hackers

From Matthias van de Meent
Subject Re: Avoid is possible a expensive function call (src/backend/utils/adt/varlena.c)
Date
Msg-id CAEze2WjOwB_w83=hh0oe=4nhzX+aoEk=MKrSRehFF00zNg412A@mail.gmail.com
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In response to Avoid is possible a expensive function call (src/backend/utils/adt/varlena.c)  (Ranier Vilela <ranier.vf@gmail.com>)
Responses Re: Avoid is possible a expensive function call (src/backend/utils/adt/varlena.c)
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On Mon, 4 Mar 2024 at 18:39, Ranier Vilela <ranier.vf@gmail.com> wrote:
>
> Hi,
>
> The function var_strcmp is a critical function.
> Inside the function, there is a shortcut condition,
> which allows for a quick exit.
>
> Unfortunately, the current code calls a very expensive function beforehand, which if the test was true, all the call
timeis wasted.
 
> So, IMO, it's better to postpone the function call until when it is actually necessary.

Thank you for your contribution.

I agree it would be better, but your current patch is incorrect,
because we need to check if the user has access to the locale (and
throw an error if not) before we return that the two strings are
equal.

Kind regards,

Matthias van de Meent
Neon (https://neon.tech)

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