I have a query which take a minimum of 30 seconds to run:
SELECT C.SITE_CD,CD.DESCRIP,COUNT(DISTINCT C.CLIENT_ID)
FROM CLIENT C, ASSESS A, CODES CD
WHERE C.CLIENT_ID = A.CLIENT_ID AND
A.ASSESS_CD = CD.CDVALUE AND
A.START_DT BETWEEN TO_DATE(:start_dt,'mm/dd/yyyy') AND...