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From:Thimble Smith Date:July 23 1999 2:24am
Subject:Re: Why this index?
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At 19:11, 19990722, Steven Roussey wrote:
>170 (63 with c=0) rows match 15950 and 19687 (3586 with c=0) rows match
>12750.
>
>With so many rows matching, it seems to me that it ought to use the 8 byte
>index(a,c) that matches the where clause rather than the first 4 bytes of
>the index(a,b).

I could be way off, but have you used isamchk -a to inform MySQL about
your tables?  It sometimes does real wonders for the proper selection
of keys to use.

Tim
Thread
Why this index?Steven Roussey23 Jul
  • Re: Why this index?Paul DuBois23 Jul
    • RE: Why this index?Steven Roussey23 Jul
      • Re: Why this index?Thimble Smith23 Jul
        • RE: Why this index?Steven Roussey23 Jul
      • RE: Why this index?Michael Widenius2 Aug
  • Schema GeneratorBradley Glonka23 Jul
    • Re: Schema GeneratorMicheal Mc Evoy23 Jul
    • Re: Schema GeneratorSasha Pachev23 Jul
  • Why this index?sinisa23 Jul
    • RE: Why this index?Steven Roussey23 Jul
  • Why this index?Michael Widenius2 Aug