Re: select query not using indexes
Hi Rick.
I am using Innodb.
When you got a "between condition" and you got the index to back it up, range scan will always be better then full index scan, 15% (which turns out in every measurement I do) is useless.
Calculating the start/stop position of the index is no time comparing to the actual scan.
In my example the scan was on an additional index (not primary). I believe that if "force index" is reducing query time from 29 minutes to 49 seconds, the optimizer is way too naive and does estimate the penalty of disk IO correctly.
Thanks for your help,
Alon.
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Re: select query not using indexes
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