These are the details of how the CAD Model data is managed in the Windchill schema when using the Rename Action in Windchill. (only feedback to David last question in this thread.)
For a CAD Model in Windchill, when you execute the “Rename” Action, the existing CAD Model row (transaction) in the EPMDocumentMaster and EPMDocmentMasterKey tables are updated.
The CADNAME, Name and DocumentNumber attribute are store in the EPMDocumentMaster table and the WTKey attribute is stored in the EPMDocumentMasterKey. For every CAD Model in your Windchill system an instance for the CAD Model is persisted into the EPMDocumetMaster and EPMDocumentMasterKey tables. The data the user enters into the “New Number” attribute on the Rename GUI is updated into both the DocumentNumber and WTKey attributes.