Re: 'Order by' clause not using indexes
MySQL will not always use the index if your query is grabbing more than 30% (this # varies) of the total data. I am not positive, but this looks like what is happening in your case. Try using a where clause (WHERE suma = ____ ORDER BY suma), then look at your explain and it should be using the suma index.
See this link for a better explanation.
http://forums.mysql.com/read.php?24,10738,10785#msg-10785
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Re: 'Order by' clause not using indexes
January 17, 2005 08:22AM
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