Oracle Forms

Hi All,

I have code run on sql very fine
the code is given below

CREATE OR REPLACE VIEW order_tracker2 AS
         SELECT 
            NVL(s.sale_order_no,0) sale_order_no,
            NVL(s.party_name,0) party_name,
            nvl(s.show,0) show,
            NVL(s.curr,0) curr,
            NVL(c.vip_cutomer,0) vip_cutomer,
            NVL(c.agent_name,0) agent_name,
            NVL(s.del_date,'01-oct-70') del_date,
            sum(NVL(sd.total_qty,0)) ITEM,
            sum(NVL(sd.total_price,0)) VALUE,
            NVL(s.TYPE,0) TYPE,
            nvl(s.comment1,0) comment1,
            NVL(S.PERFORMA_TYPE,0) PERFORMA_TYPE,
            NVL(C.CURRENCY,0) CURRENCY,
           NVL(CD.country,0) country,
           NVL(CD.CITY,0) CITY,
           NVL(CD.PIN_CODE,0) PIN_CODE,
	          NVL(SA.edit_date,sysdate) edit_date,
	     NVL(max(DM.delivery_status) keep (dense_rank first order by decode(DM.delivery_status,'DELEVERED',0,'SHORT SHIPPED',1,'PART DELIVERY',2)),'UNDELIVERED') "DELIVERY_STATUS"
       --max(DM.DELIVERY_NOTE_DATE) keep (dense_rank first order by decode(DM.delivery_status,'DELEVERED',0,'SHORT SHIPPED',1,'PART DELIVERY',2,3)) as DM.delivery__note_date
        FROM
         sale_order s,sale_order_audit SA,
         sale_order_detail sd,
         customer_master c,
         CUSTOMER_DETAIL CD,
         delivery_master DM
           WHERE s.id=sd.id AND s.id=sa.id(+) and S.SALE_ORDER_NO = DM.SALE_ORDER_NO(+) AND s.CONDIOTN_APPLY IS NULL AND
           s.cust_id=c.cust_id and C.CUST_ID=CD.CUST_ID(+) AND NVL(CD.ADDRESS_TYPE,'DELIVERY ADDRESS') ='DELIVERY ADDRESS'
           GROUP BY s.SALE_ORDER_NO,
                    s.party_name,
                    s.comment1,
                    s.del_date,
                    s.order_date,
                    c.vip_cutomer,
                    c.agent_name,
                    C.CURRENCY,
                    CD.COUNTRY,
                    CD.CITY,
                    CD.PIN_CODE,
                    S.TYPE,
                    S.PERFORMA_TYPE,
		                SA.edit_date,
		                --DM.DELIVERY_STATUS,
                    s.show,
                    s.curr;

But on the basis of this view i create a form and i get the error
ORA-24347: Warning of a NULL column in an aggregate function

Please Guide

Thanks And Regards
Vikas Singhal