We have stair price policy.
For the total value between 0-10000, we will give a discount, 10% off.
For the total value over 10000, we will give a discount, 15% off.
Customer bought goods for 10000 dollar and got a 15% off.
We shortly shipped goods, and customer didn't want the rest.
We cannot change the discount to 10% in this case.
How could SAP realize this kind of function?