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Re: Help needed on tuning query with join
Posted by: Mike Hillyer
Date: October 12, 2004 03:53PM

Why are you performing a LEFT JOIN? This can slow things up, what INDEXes do you have on the tables?

What does this produce?

EXPLAIN select a.id,a.lookup_data,b.source_id,b.criteria from weblogs as a, left join links as b on a.id=b.source_id where b.criteria=criteria

Mike Hillyer, Technical Writer
MySQL AB, www.mysql.com
Office: +1 403-380-6535

Blog: http://www.openwin.org/mike

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