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From:Timothy Smith Date:September 6 2001 2:16pm
Subject:Re: ORDER BY ... DESC LIMIT 1 optimization ?
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On 2001 Sep 06, Fournier Jocelyn [Presence-PC] <joc@stripped> wrote:
> It doesn't change anything, the query is still slow.

OK, I believe that the optimization is not being done because
MySQL doesn't realize that the ORDER BY is on the second part
of the same key that is used for the WHERE clause.

This might not be easy to fix in a general way, but we will
look into it.

Tim

-- 
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  /  |/  /_ __/ __/ __ \/ /    Tim Smith <tim@stripped>
 / /|_/ / // /\ \/ /_/ / /__   MySQL AB, Full-time Developer
/_/  /_/\_, /___/\___\_\___/   Boone, NC  USA
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Thread
ORDER BY ... DESC LIMIT 1 optimization ?Fournier Jocelyn [Presence-PC]5 Sep
  • Re: ORDER BY ... DESC LIMIT 1 optimization ?Timothy Smith6 Sep
  • Re: ORDER BY ... DESC LIMIT 1 optimization ?Fournier Jocelyn [Presence-PC]6 Sep
  • Re: ORDER BY ... DESC LIMIT 1 optimization ?Fournier Jocelyn [Presence-PC]6 Sep
  • ORDER BY ... DESC LIMIT 1 optimization ?Michael Widenius6 Sep
  • Re: ORDER BY ... DESC LIMIT 1 optimization ?Paul Cadach6 Sep
  • Re: ORDER BY ... DESC LIMIT 1 optimization ?Fournier Jocelyn [Presence-PC]6 Sep
  • Re: ORDER BY ... DESC LIMIT 1 optimization ?Paul Cadach6 Sep
  • Re: ORDER BY ... DESC LIMIT 1 optimization ?Fournier Jocelyn [Presence-PC]6 Sep
    • Re: ORDER BY ... DESC LIMIT 1 optimization ?Timothy Smith6 Sep
      • Re: ORDER BY ... DESC LIMIT 1 optimization ?Michael Widenius6 Sep
      • Re: ORDER BY ... DESC LIMIT 1 optimization ?Michael Widenius16 Jan
  • Re: ORDER BY ... DESC LIMIT 1 optimization ?Paul Cadach6 Sep