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Re: Query Optimizer Problem - OrderBy - 5.0.51 to 5.5.27
Posted by: Rick James
Date: September 06, 2012 10:42PM

Your test case does not prove anything.
* Only 1 row
* Selecting the entire table
* etc.
Present a more realistic test so we can discuss it further.
Keep in mind that if you fetch only a small number of rows, the index may be used. If you fetch most of the table, it is likely to be faster to ignore the index and scan the entire table, even if it adds a "filesort".

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Query Optimizer Problem - OrderBy - 5.0.51 to 5.5.27
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Dominik Bieringer
September 05, 2012 02:57AM
Re: Query Optimizer Problem - OrderBy - 5.0.51 to 5.5.27
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Øystein Grøvlen
September 06, 2012 04:32AM
Re: Query Optimizer Problem - OrderBy - 5.0.51 to 5.5.27
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Rick James
September 06, 2012 10:42PM


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