ITEC 3335 Database Development Fall 2018 Final Examination. Last Name: First Name: Student Id:

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1 ITEC 3335 Database Development Fall 2018 Final Examination Last Name: First Name: Student Id: Number: Time allowed: one hour 45 minutes. Total score: 112 points. Thus, this represents a bonus of 12 points for you to pursue. Closed book examination but a cheat sheet allowed. Answer all questions. Turn in both question and answer sheets (if needed). Academic honesty policy will be followed strictly. Cheating will be pursued vigorously and will result in a failing grade of D or below, a permanent academic record, and possibly other more serious penalty! (1) [12 points] Short questions. Consider the relation R(A,B,C,D). Provide a sample set of functional dependencies, F, for R so that R satisfies each of the following statements. Make F as simple as possible. (a) is answered for you as an example. (a) The highest normal form of R is 1NF. (R is in 1NF and not 2NF). For example, F = {A->B} (b) The highest normal form of R is 2NF. (c) The highest normal form of R is 3NF. (d) The highest normal form of R is BCNF.

2 (2) [20 points] Write a simple Python program, t3.py, to connect to the database toyu, to show the information about class offerings of a particular course in a format as shown by the example below. Two command line arguments accepted by the program are the rubric and number (e.g. CSCI and 4333 below). Assume no error in the command line arguments and that there will be at least one course offering of any course input to the program. Note that the id, semester and year are shown for each class. For example: You program can use the following Python program to make the MySQL connection to the toyu database. dbconfig.py: import configparser # simplistic and no error handling. def get_mysql_param(filename='dbconfig.ini', section='mysql'): config = configparser.configparser() config.read(filename) return config['mysql'] A skeleton is provided for you: from dbconfig import * import pymysql # establish database connection to the Toy University DB. db = get_mysql_param() cnx = pymysql.connect(user=db['user'], password=db['password'], host=db['host'], database=db['database']) cursor = cnx.cursor() # Your code here. # Answer in the next page. # No need to copy the skeleton again. cnx.close()

3 Answer of (2):

4 (3) [35 points] Use the Toy University (toyu) to answer the following queries with SQL. The detail of toyu is provided in a separate sheet. (a) All classes and their grades taken by CINF majors in the following format. (b) All course names that faculty Paul (first name) Smith (last name) taught in the following manner.

5 (c) Students who have taken both classes with id 10,000 and 10,001, and their grades in these two classes in the following manner. (d) List the names of faculty members with the numbers of advisees in the following manner. Only list those with 2 or more advisees.

6 (e) List the names of faculty members with the numbers of advisees, and the number of classes taught in the following manner.

7 (4) [26 points] Cleary circle T (True) or F (False) (a) [T or F] If AB is the only candidate key in R(A,B,C), C is a non-prime attribute. (b) [T or F] Database account management is a part of the job of a database administrator. (c) [T or F] It is acceptable to not explicitly specify a storage engine in a CREATE TABLE statement in MySQL, (d) [T or F] It is possible to delete multiple rows using a single DELETE statement in MySQL. (e) [T or F] In DBMS, a block is usually declared to be as small as possible to minimize its read time. (f) [T or F] Python is not an object-oriented language. (g) [T or F] In PyMySQL, a cursor can be used to iterate through the results of a SQL statement. (h) [T or F] In F = {A->B, AC->D, AB->D}, A+ = ABD. (i) [T or F] In the relational model, a superkey is also a candidate key. (j) [T or F] The result of executing an UPDATE statement in SQL may not actually make any change on the database. (k) [T or F] It is possible for a relation to have no prime attribute. (l) [T or F] A relation in 3NF is also in 2NF. (m) [T or F] If the relation R(A,B,C) is in 3NF, it is also in BCNF.

8 (5) [10 points] Given R(A,B,C,D) with F = {C->A, B->D, C->B, B->A} (a) Find A+, B+, C+ and D+. (b) What are the candidate key(s)? (c) What is the highest normal form? (d) If R is not in BCNF, can you decompose it into relations in 3NF and BCNF nicely? If yes, show the decomposition? If no, why?

9 (6) [10 points] Consider the following relation, Coaching, that stores coaching information. Coaching(StudentId, StudentFName, StudentLName, CoachId, CoachFName, CoachLName, Since, MonthlyFee) A student (with unique id StudentId, and name StudentFName plus StudentLName) can hire any number of coaches for coaching. A coach has an unique id (CoachId) and a name (CoachFName, CoachLName). When a student hires a coach, the starting date and monthly fee are stored in the attributes Since and MonthlyFee respectively. If a student hires the same coach more than once, only the most recent hiring is recorded in the table. (a) What are the functional dependencies? (b) What are the candidate keys? (c) What is the highest normal form and why?