Entity types are collections or groupings of entities that share a common description and attributes. Entities are anything of relevance to a business that the business wants to keep information about.
To illustrate the difference between entity types and entities, let us use an example from the XYZ Health Clinic. John Doe can be a patient of the XYZ Health Clinic. Mary Smith can be a Doctor who works at the XYZ Health Clinic. Both are entities, things that are relevant to the business that the business wants to keep information about. However, they are entities of different entity types. John Doe is an entity of the entity type Patient, and Mary Smith would be an entity of the entity type Care Provider. This is because their descriptions are different. The description for a patient can be someone who seeks treatment at the clinic, whereas the description for the care provider can be someone who provides treatments at the clinic. Their attributes (attributes are discussed in Attributes) are likely different as well.
Entity types (not the entities within them) are depicted in the Data Model Diagram and fall within Subject Areas.
The diagramming notation for entity types is a red box. The naming convention for entity types is a singular noun.
Based on our interview with the President of eGolf Services, what might be candidate entity types within the Golfers subject area?
|
Copyright © 2013 CA.
All rights reserved.
|
|