我有2表客戶和訂單，並找到客戶ID有最大的訂單

Question

tbi_Customer    tbl_order 
CustId int    orderid int 
Customer no    OrderName varchar(50) 
         CustId int 

Answer 1

試試這個

select top 1 a.customerno,b.totalorder from tbl_Customer as a 
join (select custid,count(custid) as totalorder from tbl_order group by custid) b on a.custid=b.custid 
order by b.totalorder desc 

Answer 2

由於沒有OrderAmount類型列，我假設你需要的是訂單的最大數量。

select top 1 
C.[Customer Number], 
count(C.[Customer Number]) as [Number of Orders] 
from tbl_Customer C join tbl_order O 
    on C.CustId = O.CustId 
group by C.[Customer Number] 
order by 2 desc