DSO Update Rules: Key Figure update types

Hi All,

First wanna thank SDN community for helping all those who are in needy.

The Datasource I am using is of the type: ABR (After Before Reverse) Logistics

My question is about the update method of the key figures in a DSO.

The two key fields are 1) Billed Quantity and 2) Exchange Rate

Will this work if I set the Billed Quantity key figure to Addition mode and Eaxchange Rate to overwrite mode???

Is it mandatory that all the key figure in a DSO have to have same udate method??? like either overwrite or Addition???????

Please help me out, this is kinda urgent and would surely award points.

Thanks a lot

SniGdha...~