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Re: Expland and slow-query don't agree
Posted by: Rick James
Date: August 04, 2014 01:23PM

What's the relevance of "Expland and slow-query don't agree"?

Sorry, but your explanation of the UNION is too much 'hand waving'; please show us the entire SELECT. (Maybe you can leave some pieces that are not problematical.)

> am I better off selecting each piece into a variable and then selecting the variables?

Better off why? A single big UNION is probably faster because of fewer statements to perform.

We'll probably need the SHOW CREATE TABLEs to see the datatypes, engines, and indexes, too.

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