ifnull没有生效

Question

select   IFNULL(Qty*ItemNetWeight,0) Weight,  IFNULL(ItemUomCode,0) code  FROM t_oc_transferorderline    where HeadID in(  select id FROM t_oc_transferorderheader where OrderType in ('ZR08')  )    and DATE_FORMAT(CreateTime,'%Y-%m-%d')=DATE_FORMAT('2016-11-08','%Y-%m-%d')select ifnull(orderNO,0) from t_oc_transferorderheader;