delete from 
    ORDERS_DTL as od
where
    EXISTS(
        SELECT
            *
        FROM
            ORDERS
        WHERE
            ORDER_NO = od.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'