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Re: Query not always using indexes
Posted by: Øystein Grøvlen
Date: January 09, 2017 02:30AM


That the optimizer will pick block nested join (BNL) over indexed join for such large tables looks like a bug in the optimizer. I hope you can file a bug at so that we can look into this. The best would be if you could attach a reproducible test case. If that is not possible, please, attach an optimizer trace for the query. (See for details.)

As a work-around, you can try turning off BNL with the NO_BNL optimizer hint. (See for details.)

Øystein Grøvlen,
Senior Principal Software Engineer,
MySQL Group, Oracle,
Trondheim, Norway

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Written By
January 06, 2017 05:48AM
January 06, 2017 12:28PM
January 09, 2017 05:18AM
Re: Query not always using indexes
January 09, 2017 02:30AM

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