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Re: Select last row that is less than or equal to a date
Posted by: Rick James
Date: January 24, 2013 10:27PM

EXPLAIN is estimating, based on statistics it gathered. EXPLAIN does not really take into account the LIMIT clause.

The way to check things is:
SHOW SESSION STATUS LIKE 'Handler%';
SELECT ...
SHOW SESSION STATUS LIKE 'Handler%';
Then look at the differences in various Handler counters.

This is clearly the best index for all of those SELECTs:
index PlayerDate ( HistoryPlayer, HistoryDate )

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Re: Select last row that is less than or equal to a date
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January 24, 2013 10:27PM


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