delete from
    ORDERS
where
    ORDER_NO in (
        select
            A.ORDER_NO
        from
            ORDERS as A
        join ORDERS_DTL as B on A.ORDER_NO = B.ORDER_NO
        where
            A.ORDER_DATE between '2010-01-01' and '2010-12-31'
    )
;

delete from
    ORDERS_DTL
where
    (ORDER_NO, LINE_NO) in (
        select
            A.ORDER_NO,
            B.LINE_NO
        from
            ORDERS as A
        join ORDERS_DTL as B on A.ORDER_NO = B.ORDER_NO
        where
            A.ORDER_DATE between '2010-01-01' and '2010-12-31'
    )
;