Modeling Relationships . Farrokh Alemi, Ph.D. Definition of Hierarchy. A collection of super and sub entities. A super entity is the broadest definition of several sub entities. A sub entity is an entity that inherits its relationship from another entity. . Definition of Relationship.
Farrokh Alemi, Ph.D.
Stabilize the overall model with respect to new requirements.
New Requirement: “Patient of record” becomes inactive but the system does not purge it
The first issue is whether the sub entity is distinct form other entities
The third issue is whether the discriminator attribute in the super-entity applies to all sub types
The importance of good entity and attribute definitions