The purpose of data modeling is to define the structure of the data storage. During the master data processing, a change request is used that stores the master data changes in a staging area. The data model can define a reuse area that is used for data storage after the change request processing has been completed and the related data has been activated. In this case, the system moves data from the staging area to a storage location that is connected by the access class of the reuse area. This storage location is called active area.

If there is no reuse area defined, the same database tables that are used for the staging area, are also used to store active data. Then, no access class is involved, the system does not move data from one location to another, and MDG is used as the active area.