Question

I have the following Table named Order

Orders Table
___________________________________________________
orderiD | userId | OrderType | Order_Date | Amount
________|________|___________|____________|________
1          1          0         12/12/2009    1
2          1          1         13/12/2009    2
3          1          1         14/12/2009    3
4          2          0         12/12/2009    4
5          2          1         16/12/2009    2
6          1          0         14/12/2009    5
7          2          1         17/12/2009    4
8          2          0         10/12/2010    2
___________________________________________________

I need to create query which returns user id with maximum SUM of purchases.

I tried the following

Select MAX(GRP.sumAmmount), o.userId join
(Select SUM(o.Amount) as sum_ammount, o.userId as UID from Orders GROUP BY(o.userID)) as GRP on o.userId=GRP.UID GROUP BY(GRP.UID)

But I believe I’m missing something.

Can you help?

Answer 1

If I understand your question correctly, you want to return the UserID which has the maximum SUM (total) of purchases. So the above records will result:

UserID  Total Amount
  2         12

And the simpliest solution would be:

SELECT UserID, SUM(AMOUNT) as TotalAmount
FROM Orders
GROUP BY UserID
ORDER BY TotalAmount DESC
LIMIT 1

I’m ready to edit this if I’m wrong. 🙂
(PS: Please add your desired result)

Thanks.

UPDATE 1

Derived from you query:

  Select  MAX(SUM(o.Amount)) as sum_ammount, 
          o.userId as UID 
    FROM  Orders o
GROUP BY  o.userID
ORDER BY  sum_ammount DESC
   LIMIT  1