Column is invalid in select

Question

How I will properly do this:

Customer

CusID, CusLname, CusFname, CusMname, CusAddress, CusEmailAdd

Order

OrderID,  Ord         


        

Answer 1

I also find first answer to be the best, but in SQL2005 CTEs came into existence and they can help obtain better readability:

;with order_cte as (
    select count(OrderID) cnt, CusID
    from Order o 
    group by CusID
)
select cnt, c.CusID, CusLname, CusFname, CusMname, CusAddress, CusEmailAdd
from Customer c 
   join order_cte o on c.CusID = o.CusID
order by c.CusID