From: Dan Nelson
Date: December 28 2001 10:09pm
Subject: Re: How to optimize this
List-Archive: http://lists.mysql.com/mysql/94940
Message-Id: <20011228220907.GH77887@dan.emsphone.com>
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In the last episode (Dec 28), Goran Krajacic said:
> How to optimize this query:
> 
> SELECT col1, col2, MAX(col3) FROM Table WHERE col4>2 AND col5 = 2 GROUP BY col3 LIMIT 1;

Try a compound index on (col5,col4), or if you really want speed,
(col5,col4,col3,col2,col1), which will let mysql use the index for the
SELECT fields as well :)

Your query can also be written 

SELECT col1, col2, col3 FROM Table WHERE col4>2 AND col5 = 2 ORDER BY col3 DESC LIMIT 1;

, which might be faster.

-- 
	Dan Nelson
	dnelson@stripped