Diagnosis
For entity types with storage and use type 3 for which the checktable is predefined by the data element or domain, the other key fieldsin the check table must be mapped using relationships with Leading
as the relationship type. The assignment between the leading entitytype and the additional key field can only be made if the data elementor the related check table can be assigned uniquely. In this case, aunique assignment is not possible.

System Response
The data model cannot be saved or activated.