DELETE FROM ORDERS_DTL
WHERE ORDER_NO IN
(
	SELECT ORDERS_DTL.ORDER_NO
	FROM ORDERS,ORDERS_DTL
	WHERE ORDERS.ORDER_NO = ORDERS_DTL.ORDER_NO
	AND ORDER_DATE BETWEEN '2010-01-01' AND '2010-12-31'
);
DELETE FROM ORDERS
WHERE ORDER_DATE BETWEEN '2010-01-01' AND '2010-12-31'
;