SQL Server 2019

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create table item (ID int, code int)
create table Item_Order (Item int, Box int, Quantity int)
create table Invoice_Item (Item int, Num decimal, Quantity int)
insert into Item values(1, 7502)
1 rows affected

insert into Item_Order values(1, 30, 15000)
1 rows affected

insert into Item_Order values(1, 12, 6000)
1 rows affected

insert into Invoice_Item values(1, 5.64, 10)
1 rows affected

insert into Invoice_Item values(1, 2.4, 8)
1 rows affected

    select a.ID
           , a.OrderB
           , a.OrderQ
           , b.Quantity SellQ
           , b.Num SellN
    from 
    (SELECT Item.ID
           , Item_Order.Box As OrderB
           , Item_Order.Quantity As OrderQ
           , row_number () over (order by Item.ID) rn
    FROM Item 
    left outer JOIN Item_Order ON Item.ID = Item_Order.Item) a
    left outer join (select Item
                            , Num
                            , Quantity
                            , row_number () over (order by Item) rn 
                     from Invoice_Item ) b
    on a.ID = b.Item
    and a.rn = b.rn


ID
OrderB
OrderQ
SellQ
SellN


1
30
15000
10
6

1
12
6000
8
2