In order to determine the requirements for the new Customer Tracking System, several JAD sessions, interviews, and observations were conducted. Resulting information from these requirements determination methods was useful in the preparation of the Customer Tracking System’s data-flow diagrams.

One afternoon while you are working on the Customer Tracking System’s data-flow diagrams, Jim Woo stops by your desk and assigns you the task of preparing a conceptual entity relationship diagram for the Customer Tracking System. Later that afternoon, you review the requirements-determination phase deliverables, including the data-flow diagrams you have just finished preparing. Your review of these deliverables suggests that the Customer Tracking System’s primary objective is to track and forecast customer buying patterns. Additionally, in order to track a customer’s buying habits, an order history must be established, satisfaction levels assessed, and a variety of demographic data collected. The demographic data will categorize the customer according to type, geographic location, and type of purchase. Customer Tracking System information will enable Pine Valley Furniture to better forecast its product demand, control its inventory, and solicit customers. Also, the Customer Tracking System’s ability to interface with the WebStore is important to the project.

a. What entities are identified in the previous scenario? Can you think of additional entities? What interrelationships exist between the entities?

b. For each entity, identify its set of associated attributes. Specify identifiers for each entity.

c. Based on the case scenario and your answers to parts a and b, prepare an entity-relationship diagram. Be sure to specify the cardinalities for each relationship.

d. How does this conceptual model differ from the WebStore’s conceptual model?