DELETE FROM ORDERS_DTL
WHERE EXISTS
(SELECT * FROM ORDERS_DTL INNER JOIN ORDERS ON ORDERS.ORDER_NO = ORDERS_DTL.ORDER_NO
 WHERE ORDERS.ORDER_DATE BETWEEN '2010-01-01' AND '2010-12-31')
;
DELETE  FROM ORDERS
WHERE ORDERS.ORDER_DATE BETWEEN '2010-01-01' AND '2010-12-31';