Describe and discuss the main elements of the Entity-Relationship (E-R) model. Include an example

What will be an ideal response?


The E-R model is basically made up of entities, attributes and relationships. Entities represent the things people want to keep track of, such as customers and products. Each "thing" is presented by an entity or entity class—in this case CUSTOMER and PRODUCT. Individual members of each entity class are called entity instances—for example CUSTOMER John Smith and PRODUCT Canned Tomato Soup. Each entity is described by a set of attributes. For example, a CUSTOMER will have a CustomerNumber, a LastName and a FirstName, while a PRODUCT will have a ProductNumber and a Description. These, of course, have specific values for each entity instance. Finally, the entities are connected by relationships. There are relationship classes between entity classes and relationship instances between entity instances. For example, in general a CUSTOMER buys a PRODUCT, and a PRODUCT is sold to a CUSTOMER. Specifically, CUSTOMER John Smith buys a PRODUCT Canned Tomato Soup.

Business

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What are the different income-distribution patterns? How does income distribution in the economies affect the marketing decision of the firms?

What will be an ideal response?

Business

Sales forecasts, expense forecasts, and break-even analysis are usually found in the section on financial projections in the marketing plan

Indicate whether the statement is true or false

Business

A culture that has neither strong norms about what the “right” behavior to show is nor strong means of sanctioning the wrong behavior is said to be _____.

a. socially corrupt b. socially ignorant c. culturally tight d. culturally loose

Business

Exclusive distribution

A. usually involves intermediaries who are willing to take over all responsibility for promoting the producer's product. B. should generally be used only if it is not possible to generate intermediary interest in intensive distribution. C. is an arrangement between a producer and intermediary that is illegal for most types of products in the United States; thus it is not very common. D. is legal as long as it does not involve vertical channel arrangements. E. None of these answers is correct.

Business