SET @STARTDATE := '2011-06-20';
SET @ENDDATE := '2011-06-22';
SELECT COUNT(*) AS 'NUMBER OF BUGS OPEN'
FROM BUGS
WHERE ( OPEN_DATE <= STR_TO_DATE(@STARTDATE, '%Y-%M-%D')
AND CLOSE_DATE > STR_TO_DATE(@STARTDATE, '%Y-%M-%D')
) AND (
OPEN_DATE <= STR_TO_DATE(@ENDDATE, '%Y-%M-%D')
AND CLOSE_DATE > STR_TO_DATE(@ENDDATE, '%Y-%M-%D')) ;