Modeling the Extension of an ER Diagram{Comments Off on Modeling the Extension of an ER Diagram}

by Ahlyzik M

When solving a design issue with the business rules, Entity relationship diagrams are used to consolidate given objects in the business process. The author discusses the concepts of the deeper level of taxonomy in database design, otherwise known as an Enhanced Entity Relationship diagram. The weaker entities are known as a subtype which is to indicate that the entity is an extension of the main entity called the super type. This is the design standard used when categorizing a group of individuals or entities in a hierarchical fashion. Disjoint constraints are used to identify whether the entity can be a member of one or more subtypes in the super-subtype relationship.


This modification to the best practices of database design allows for a great amount of flexibility and efficiency. In turn, this will create an environment where the businesses can best utilize the efficiency of the design and be able to be a prosperous business. There is quite a challenge when designing databases when there is a group of data that has a number of attributes in common and the availability of having an EER diagram is unavailable.

In order to overcome and obstacle such as this, one must utilize the concepts of both specialization and generalization. I believe that these are great concepts to use when designing a database considering that it allows for a hierarchical structure which makes is easier to read. The ability to create a structure that is easy to read and is efficient is key since the business is heavily reliant on the IT infrastructure. ER diagrams will continue to be used for some time as the desire to both create and consume data grows in the coming years.


Sikha Bagui. (2011) Extended Entity Relationship Modeling. IRMA International. Retrieved October 16, 2011, from