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Re: Desperate: BETWEEN and ORDER BY on different columns
Posted by: Joachim Berger
Date: September 05, 2011 01:03AM

Hi Rick,

thanks for the answer. The problem with the last example (the one with the 'bulky' fields) is that it's still using filesort for the result table (<derived2>).

I don't know if it's better to indeed have a filesort here, or just have a less selective index on just (sex, rnd) and do the "WHERE birthdate..." part in the outer query. In this case, no filesort is being used, but more rows are returned of course.

Any suggestions?

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Re: Desperate: BETWEEN and ORDER BY on different columns
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September 05, 2011 01:03AM


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