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From:Johan De Meersman Date:March 31 2011 4:06pm
Subject:Re: A common request
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----- Original Message -----
> From: "Gregory Magarshak" <greg@stripped>
> I am guessing that the MySQL indexes map indexed fields (fb_uid) to the
> primary key (id) so I wouldn't have to touch the disk. Am I right
> about that?

Correct for InnoDB, but MyISAM maps every index straight onto records. That's why
secondary indices are slightly more performant on MyISAM tables - InnoDB needs to do the
extra primary key lookup - which it of course is bloody good at :-)


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Bier met grenadyn
Is als mosterd by den wyn
Sy die't drinkt, is eene kwezel
Hy die't drinkt, is ras een ezel
Thread
A common requestGregory Magarshak29 Mar
  • Re: A common requestPeter Brawley29 Mar
    • Re: A common requestGregory Magarshak29 Mar
      • Re: A common requestPeter Brawley29 Mar
        • Re: A common requestGregory Magarshak31 Mar
          • Re: A common requestGregory Magarshak31 Mar
            • Re: A common requestJohan De Meersman31 Mar
          • Re: A common requestmos31 Mar
            • Re: A common requestJohan De Meersman31 Mar
            • Re: A common requestmos31 Mar
              • Re: A common requestWm Mussatto31 Mar
  • Re: A common requestSander de Bruijne29 Mar