SAP MRP Questions...

Hoping to find some help here from some knowledgeable experts:

Situation: Trying to create an program to extract MRP results out of SAP(basically what you see in MD04).

Question 1: Does anyone know a way using the tables available through the ABAP interface to determine if a part has "activity" (has supply or demand or onhand) prior to performing a bunch of expensive queries? I really only want to extract the parts that have this but I can't figure out how to do this efficently.

Question 2: Trying to find an easy way to understand what SAP considers the a) Total active demand for a part is, b) Total active supply for a part is and c) Ending inventory balance based on MRP results. Does anyone know of a way to efficently determine this on a part by part basis?

Thanks in advance for any help anyone can provide me!

Regards,

Kris