Sum Based on The Value of Another Group

Question

I'm using RS 2005 and trying to accomplish the following:
Here is the detail data for those customers with negative balance. For example cust2 = -50 and cust3 = -30
Cust ID    Ord #   Balance
cust1        1          30
cust1        2          80
cust2        1        100
cust2        2       -150
cust3        1        100
cust3        2         70
cust3        3       -200
cust4        1       100
cust4        2         50
cust5        1       250
cust5        2         20
Total (net) balance for cust1 is 110
Total (net) balance for cust2 is -50 (100 + -150)
Total (net) balance for cust3 is -30 (100 + 70 + -200)
Total (net) balance for cust4 is 150
Total (net) balance for cust5 is 270
i have to aggregate the customer balance in group A (group by Cust ID)
For group B, Division - I only want sum the  balance of the customers within that division that have a negative balance (the balance aggregate in group A).
so the Total for Division (group B) is  -80 (bal of cust2 + bal of cust3)
in summary, i have to aggregate the balance for each customer, base on the balance of each customer (neg bal only), i aggregate the balance for the Division.  Your help/suggestion is greatly appreciated.

Answer 1

Hi Bryan,
First, did you trying to do this at query level or at RS using grouping and expression?
With query, to get aggregate for each customer, simply do:
select distinct Cust_ID, TotalBalance = sum(Balance)
from <your table>
group by Cust_ID
To get the aggregate for division, try:
select Total = sum(case when TotalBalance > 0 then 0 else TotalBalance end)
from (
select distinct Cust_ID, TotalBalance = sum(Balance)
from <your table>
group by Cust_ID
) t1
** Didn't see this has been replied.