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Re: Long execution time despite LIMIT 3
Posted by: Rick James
Date: June 23, 2011 08:53AM

That's because InnoDB (not MyISAM) silently appends the PRIMARY KEY fields to every secondary key. So, effectively, those indexes are identical. (Sorry, I should have included id so that this puzzle would not arise.)

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Re: Long execution time despite LIMIT 3
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June 23, 2011 08:53AM


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