Entity-relationship modeling

The Entity-Relationship (ER) model and its accompanying diagrams are very in-demand for use in database design and systems analysis. Numerous looks and articles just provide a definition if every modelling component and give-examples of the pre-built ERDs. As a result, neophytes in data modeling face difficulty in learning how to approach a given problem, what question to ask to build a model, what rules to utilize while constructing an ERD, and why one diagram is better than another. This paper presents step-by-step-guidelines, a set of decision rules proven to be useful in establishing ERDs, and a case study problem with preferred answer as well as a set of incorrect diagrams for the problem. These guidelines are decision rules have successfully used in beginning Database Management System course for the last five years.