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Expland and slow-query don't agree
Posted by: Aram Mirzadeh
Date: August 03, 2014 06:24AM


Odd question. In my slow log I'm seeing that a call to a SPROC is going through millions of rows and returning only a few.

EXPLAIN-ing the SPROC, which is a multi-table union sql to get a few data points. Every select (except 2) within the union is using the right index. The 2 that are not are 1) Select a count for division, which is derived into the outer Select and 2) the last union that puts all of the selects together.

It is a very long Union (12 selects + 1 inner select in all), am I better off selecting each piece into a variable and then selecting the variables?

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Written By
Expland and slow-query don't agree
August 03, 2014 06:24AM
August 04, 2014 01:23PM

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