A DFA class is stored as an item. A new dataset type named DFA_KF is created and is pasted into an item revision with a Specification relation. The DFA file is stored as a named reference to the dataset. When the DFA file is imported to the database, a relation is created between the DFA file (class) and it's mix-ins and also the link between the DFA file (class) and all the Child classes used in that file. The type of this link is the same as that between the part file and the DFA files (classes).

A new relation type is created. The NX Part, Mix-ins, and Child, are all linked by this relation type to the DFA Class. This is needed, for "Where Referenced" options in Teamcenter. As all relation types are the same, "Where Referenced" on any class results in providing all the classes and the NX parts referencing it.

The following diagram illustrates this concept using My_door item as an example.

In the above diagram, if you "Where Used" on the class My_knob, the result is my_door.dfa, part_1.prt and part_2.prt.

The NX Part contains references to its DFA classes. We need to determine which classes are referenced by a particular part file and conversely, which part files have been referencing a particular class. This is needed because if a user is interested in changing a particular class, the part file that references this class must be identified for possible update.