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Re: Query not always using indexes
Posted by: Peter Brawley
Date: January 06, 2017 12:28PM

In the slow run, ref=ALL means the optimiser could not find an `sch` index that would be faster than a table scan. To have a chance at suggesting an improvement, we'd need to see the two update queries and Show Create Table results for the referenced tables.

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

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