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Re: How to optimizate COUNT query with multiple LEFT JOIN
Posted by: Peter Brawley
Date: June 01, 2021 12:19PM

To spare us the ads, the readability issues, and the risks inherent in links of unknown provenance, please post the Explain result here inside BBCode code tags.

1 sec isn't bad for aggregation over a dozen joins. (Why would market research require blazing speed?)

Why Left Joins? Your Where conditions turn them into implicit Inner Joins, and Inner Joins benefit more from covering indexes, which might help fractionally.

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Re: How to optimizate COUNT query with multiple LEFT JOIN
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June 01, 2021 12:19PM


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