Project Statement:  Humungo Video Stores has decided to store information about videos and DVDs that they sell, and information about the associated films in a web-based database.  You are in charge of designing a conceptual database schema (Entity-Relationship Diagram) that reflects the company's information needs.

Data Description:  The following is a list of the data that must be stored in the database.

• Each film has a title, the date that it was released, running time, a budget, a director, the studio that produced it, and the screenwriter.
• Each actor who has acted in one of the films sold by Humungo Video has a name (first and last), a birthdate and a gender.
• Each film has several actors associated with it.  For each actor in a particular film, we need to keep track of the part he/she played, and the salary paid to the actor by the studio.  Each actor has a minimum salary they will take for acting in a film.
• The database must store information about the studios that produce the films. This should include a name, an address and a web site.
• Humungo Video would like to provide on-line shopping of their inventory. Therefore, they should keep track of all of the items that they have to sell. For each item, they need to store the film itself, the price of the item, the date the item was released, the format (VHS, DVD, etc), any bonus materials included with the item, and the number in inventory.
• The database will store information about shoppers that have bought, or plan to buy items from the web site. This information should include a name (first and last), an address, and a credit card number.
• To make shopping more convenient, the web site will provide a shopping cart to hold items that a shopper might want to purchase. The cart should contain a reference to the shopper, a reference to the item, and the quantity that the shopper wishes to purchase.

Remember that all of the data above should be represented in the design, but some of it will be represented through entities, and others through relationships. Carefully choose how you design the database.

Database Design:

1. Design a conceptual database schema for Humungo Video Stores according to the above information needs, and draw the corresponding Entity-Relationship diagram.  Be sure to indicate primary key attributes. Identify cardinality constraints for relationships sets, and indicate participation constraints for entity types and relationships.
2. Identify reasonable integrity constraints that you are unable to capture using the ER modeling constructs.  State them in natural langauge and give a brief explanation why you could not express them in the ER schema.
3. Briefly identify the relations (tables) you can derive from your ER diagram. 
4. Are there any relationship types in your ER design for which you do not need a table in the relational mapping?  Explain your answer.
5. If you were going to use the Enhanced Entity Relationship Model to design this database, describe some refinements you could make to the design. Include at least two suggested refinements.

1. The Entity-Relationship diagram for the Humungo Video Stores database schema.
2. Answers to questions 2 through 5 above.
3. Please turn in all of the above in hard copy, and typed by class time on October 7.