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Understanding Referential Integrity
When a content management system has referential integrity, it means that relationships between objects are managed in the system. This ensures that an object referenced by another object cannot be deleted from the content management system.
For example, assume that you have two document objects, Doc1 and Doc2, and both documents contain the document object Copyright Statement. If you were editing Doc1 and removed the reference to Copyright Statement, you may be tempted to delete the Copyright Statement object from the PTC Server, not knowing that it is referenced elsewhere. The PTC Server connection, however, keeps track of references and would prevent you from deleting an object that was referenced in another document object.
You can use the View > Used By operation in the Browser to determine which objects in a PTC Server reference the selected object.