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Re: Any way to force sequential reading of index blocks?
Posted by: Engel Sanchez
Date: August 20, 2009 01:29PM

I just found the IGNORE KEY command, and it solves my problem. So, when you have a large indexed MyIsam and you need to run a query that requires scanning of the entire table, you can force MySQL to scan the table reading the row data sequentially instead of reading it through the index, which results in fewer random seeks. This improved my running time 20 fold:

select max(value3) from test_table ignore key(primary)

(from the same test_table example in my original post)

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Re: Any way to force sequential reading of index blocks?
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