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Re: order by primary key slowly
Posted by: Rick James
Date: April 12, 2016 07:42PM

Maybe the real answer is "Don't do that!".

Why are you using huge offsets? Are you walking through the table? Is a human doing such? I doubt it. It would be painfully tedious to press the Next button 100000 times.

A better way is to "remember where you left off". See my blog on such: http://mysql.rjweb.org/doc.php/pagination

Back to the question and replies...
* Neither query sorts. The one using the 'type' index has no ORDER BY; the one by 'id' takes advantage of the table being ordered by 'id'.
* When using LIMIT, EXPLAIN often lies in the 'Rows' and 'Filter' columns.
* Did you "time" your queries twice? The first time may be slow because of I/O; the second may be faster because of caching. Use the second.
* Add SQL_NO_CACHE (or turn off the Query cache) so that the QC does not give you a time of "0.00 seconds".

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