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From:Sergei Golubchik Date:October 8 2009 1:55pm
Subject:Re: bzr commit into mysql-5.1-bugteam branch (epotemkin:3147)
Bug#34384
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Hi, Evgeny!

On Oct 08, Evgeny Potemkin wrote:
> 
>  3147 Evgeny Potemkin	2009-10-08
>       Bug#34384: Slow down on constant conversion.
>       When values of different types are compared they're converted to
>       a type that allows correct comparison. This conversion is done
>       for each comparison and takes some time. When a constant is
>       being compared it's possible to cache the value after conversion
>       to speedup comparison.

On IRC you told me that "SELECT caches the converted value, while UPDATE
does not". Where/how SELECT was doing it ? Why UPDATE wasn't ?

Why do you need to introduce the concept of "late caching" ?

Regards / Mit vielen Grüßen,
Sergei

-- 
   __  ___     ___ ____  __
  /  |/  /_ __/ __/ __ \/ /   Sergei Golubchik <serg@stripped>
 / /|_/ / // /\ \/ /_/ / /__  Principal Software Engineer/Server Architect
/_/  /_/\_, /___/\___\_\___/  Sun Microsystems GmbH, HRB München 161028
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Thread
bzr commit into mysql-5.1-bugteam branch (epotemkin:3147) Bug#34384Evgeny Potemkin8 Oct
  • Re: bzr commit into mysql-5.1-bugteam branch (epotemkin:3147)Bug#34384Sergei Golubchik8 Oct
    • Re: bzr commit into mysql-5.1-bugteam branch (epotemkin:3147) Bug#34384Evgeny Potemkin9 Oct
      • Re: bzr commit into mysql-5.1-bugteam branch (epotemkin:3147) Bug#34384Roy Lyseng9 Oct
        • Re: bzr commit into mysql-5.1-bugteam branch (epotemkin:3147) Bug#34384Evgeny Potemkin13 Oct
  • Re: bzr commit into mysql-5.1-bugteam branch (epotemkin:3147) Bug#34384Øystein Grøvlen9 Oct
  • Re: bzr commit into mysql-5.1-bugteam branch (epotemkin:3147)Bug#34384Sergei Golubchik14 Oct