if object_id('dbo.Viw_PO_Item_List') is not null
drop view dbo.Viw_PO_Item_List
go

Create view Viw_PO_Item_List
as
select 
pono,
Item,
HPN,
CPN,
MPN, 
material_nm as Description,
uom
from ord_item where 
item in(select distinct item  as item 
from ( select pono,Item,HPN,CPN,MPN, material_nm,uom 
from Ord_item 
group by  
pono,Item,HPN,CPN,MPN,material_nm ,uom 
)a)