Accounting interim data delta

[liran kessel]

Hi,

we have a radius server installed collecting accounting data from a Cellular network.
Currently we receive the Interim update every 30 minutes, and it updates the radacct table correctly .

What we need is to be able to know what was the delta of acctinputoctets and  acctoutputoctets that was received in this event , in comparison to the data that was already in the DB from the previous notifications.
Can I somehow enter this delta into a different table that will show me the usage for each notification?

Thanks
Liran