1. Consider the following functional dependencies, to be used in the analysis of a database design for the Furman Air enterprise of the first exam:

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1 CSC-341 Exam #2 October 20, 2009 Name: 1. Consider the following functional dependencies, to be used in the analysis of a database design for the Furman Air enterprise of the first exam: Attributes Pilot Pilot Name Date of Birth Date of Hire Flight Date (of flight) Departure Time Arrival Time Passenger Passenger Name Address (of passenger) Telephone (of passenger) Fare Reservation Date Serial Model Passenger Capacity Year Built Manufacturer Functional Dependencies Pilot Pilot Name, Date of Birth, Date of Hire Flight, Date (of flight) Departure Time, Arrival Time Passenger Passenger Name Passenger Passenger Name, Address (of passenger), Telephone (passenger) Flight, Date (of flight), Passenger Fare, Reservation Date Flight, Date (of flight) Serial Flight, Date (of flight) Departure Time, Arrival Time, Pilot Serial Model, Passenger Capacity, Manufacturer Serial Year Built, Manufacturer Model Manufacturer Design a well-structured relational database schema for this system using the data normalization technique. Progress from first to second normal form and then from second to third normal form as indicated in the steps below. [20 pts.] a. Give a relation schema in 1NF, indicating the primary key. b. Show the relation schemas in 2NF, indicating all primary and foreign keys.

2 c. Show the relation schemas in 3NF, indicating all primary and foreign keys. 2. Consider the relational schemas for the General Hardware database given on the last page of this exam. Perform the following queries using relational algebra (not SQL). Make your solutions as efficient as possible. [5 points each] a. List the names of all customer employees with the title vice president. b. List the salesperson name and product name for all sales of items that cost more than $100 for salespersons with a commission of greater than 10%. c. List the names of salespeople who sell both product number 2A and product number 1199C. d. List the names of all salespeople who have not yet made a sale.

3 3. Short Answer: [4 points each] a. Consider the City Zoo tables from the end of the exam. Give a specific example (i.e., make up some data) of each of the following actions that would lead to a violation of referential integrity: Insertion Deletion Update b. Consider the normalized schemas from problem #1. Using a specific example (i.e., make up some data), explain how an instance of data redundancy that would be possible with the 1NF or 2NF schemas is no longer possible with the 3NF schemas. Be sure to explain why the redundancy can no longer occur. c. In third normal form, the exception to the rule that a non-key attribute cannot define another non-key attribute is. a. if the defining attribute is a candidate key b. if the defined attribute is a candidate key c. if the defining attribute is a foreign key d. if the defined attribute is a foreign key e. None of the above.

4 d. Explain how functional dependency {A, G} {B, C, D, E, F, H} can be derived if these dependencies are given: A {B, C, D} B C E {F, G, H} G {H, E} Cite the axiom that you are using for each step. e. Using the City Zoo example again, what would happen if the update rule between the ENCLOSURE and ANIMAL relations is cascade and an attempt is made to change the enclosure number for Natural Area to 0913 in the ENCLOSURE relation? What if the update rule is restrict? Extra Credit: Answer question 2.c. using SQL and the IN operator.

5 Relation schemas for General Hardware Name SALESPERSON Relation Commission Percentage Year of Hire Office (FK) Customer Customer Name CUSTOMER Relation (FK) HQ City Customer (FK) Employee Employee Name CUSTOMER EMPLOYEE Relation Title Product Product Name PRODUCT Relation (FK) SALES Relation Product (FK) Office Telephone OFFICE Relation Unit Price Quantity Size (sq. ft.) Two tables for a city zoo database: Enclosure Type Size Glass Cage Fenced Yard Natural Area Fenced Yard Steel Cage 700 ENCLOSURE relation Animal Species Animal Name Enclosure Elephant Jumbo Giraffe Stretch Elephant Shirley Giraffe Necky Giraffe High Top Panda Fluffy Elephant Large Louie Elephant Charley Panda Huggy Giraffe Sarah 0912 ANIMAL relation

6 Attributes A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S Functional Dependencies A B, C, D E, F G, H I J I J, K, L E, F, I M, N E, F O E, F G, H, A O P, Q, S O R, S P S

Relational Database Model. III. Introduction to the Relational Database Model. Relational Database Model. Relational Terminology.

Relational Database Model. III. Introduction to the Relational Database Model. Relational Database Model. Relational Terminology. III. Introduction to the Relational Database Model Relational Database Model In 1970, E. F. Codd published A Relational Model of Data for Large Shared Data Banks in CACM. In the early 1980s, commercially