Conceptual, Logical, and Physical Data Models: A Simple Example


This post is a very simple, possibly over simplified, example of conceptual, logical, and physical data models.  The conceptual model includes business objects and the cardinality between the objects.  The logical model includes the cardinality, attributes, and addresses potential primary and foreign keys.  The physical model includes table names, column names, and data types.  The problem with hiding the potential complexity of this process is giving the impression that data  modeling (aka modeling business processes) is easy and fast and therefore trivial.  The modeling process is not trivial.  Devoting adequate time to designing, implementing, testing, and redesigning the data models in a project can be the difference between a impactful project  and having to start over after the business objectives are not met.

Conceptual


Logical




 Physical

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