MySQL optimization question -- how to speed up a simple query
Here is your original query

SELECT t.price
FROM commoddb.tbcommodprices t
WHERE t.ticker='LAV05 Comdty'
AND t.whichprice='last'
t.date = '2005-09-01';


Since there is but one table in this query, all you need is a good index.

ALTER TABLE commoddb.tbcommodprices ADD INDEX (ticker,whichprice,date);


This index should now be a permanent part of the table until you decide to remove it, which I don't think you want to do. To see the table and the indexes, just do this:

SHOW CREATE TABLE commoddb.tbcommodprices\G