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Re: Puzzled: why does join run 27,252 x faster than left outer join?
Posted by: Peter Zaitsev
Date: July 21, 2005 01:00PM

Deniel,

KimSeong's diagnostics is correct. Something is broken in left join optimization which does not allow it to use "range checked" optimization. I would suggest you to test it out with latest MySQL 4.1 and if it does not work still file a bug reports.

I should also mention joins with OR as yours are inefficient in MySQL 4.1 it would be better to rewrite it to UNION or UNION ALL.

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Puzzled: why does join run 27,252 x faster than left outer join?
2334
Daniel Brennan
July 19, 2005 07:14AM
Re: Puzzled: why does join run 27,252 x faster than left outer join?
1767
Felix Geerinckx
July 19, 2005 07:30AM
Re: Puzzled: why does join run 27,252 x faster than left outer join?
1623
Daniel Brennan
July 19, 2005 07:38AM
Re: Puzzled: why does join run 27,252 x faster than left outer join?
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KimSeong Loh
July 19, 2005 06:19PM
Re: Puzzled: why does join run 27,252 x faster than left outer join?
1669
Peter Zaitsev
July 21, 2005 01:00PM


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