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From:Michael Widenius Date:August 1 1999 11:40pm
Subject:RE: Why this index?
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>>>>> "Steven" == Steven Roussey <sroussey@stripped>
> writes:

Steven> Hi!
Steven> 170 (63 with c=0) rows match 15950 and 19687 (3586 with c=0) rows match
Steven> 12750.

Steven> With so many rows matching, it seems to me that it ought to use the 8 byte
Steven> index(a,c) that matches the where clause rather than the first 4 bytes of
Steven> the index(a,b).

Steven> Steven Roussey
Steven> Network54.com

Which MySQL version are you using?

Any change you can ftp a copy of the table to

ftp://www.mysql.com/pub/mysql/secret

So that I can check this ?

You can also start mysqld with
--debug=d,info,query,warning,error,exit:o,/tmp/mysqld.trace
and run the query and then send the file /tmp/mysqld.trace to me!

Regards,
Monty
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