We have a field LZONE in Customer Master (DEBMAS) IDOC on which normal conversion rule is applied to map the values. During the initial data load it holds some dummy data as it is a mandatory field in the our SAP system. This LZONE field is further updated with actual values during the SD process in our environment. But each time the IDOC is posted the values are overwritten and get stored with dummy values from the other SAP system.
Is there any standard way besides changing Process Code to check whether if LZONE field already has a value in database and if yes, the field should not be updated and if not it should be updated via IDOCS??