CSCI DBMS Spring 2017 Final Examination. Last Name: First Name: Student Id:

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CSCI 5333.2 DBMS Spring 2017 Final Examination Last Name: First Name: Student Id: Number: Time allowed: two hours. Total score: 100 points.

1 CSCI DBMS Spring 2017 Final Examination Last Name: First Name: Student Id: Number: Time allowed: two hours. Total score: 100 points. This is a closed book examination but you can bring a cheat sheet. Answer all questions. Turn in the question paper, any answer sheets, the cheat sheet and all rough work. Plan your time well. 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. Many questions refer to the Sakila database we have used extensively in lectures and homework. Please refer to the relation schemas in the supplementary sheets to answer these questions.

2 (1) [25 points] Write a PHP program, t2.php, to accept two HTTP GET parameters cid and aid. The program displays all films with their numbers of copies in the inventory of the category cid with actor aid starring in the films. /t2.php?cid=1&aid=6 It should display the following in the browser. You may assume that there will be no error in the HTTP parameters. Please answer your question in the next page. A skeleton is provided for you: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" " <html xmlns=" <head> <meta http-equiv="content-type" content="text/html; charset=utf-8" /> <title>csci DBMS Spring 2017 Final Examination, Question 1</title> </head> <body> <?php // Minimally documented. include('dbconfig_sakila.php'); Your code: write it in the next page. $mysqli->close();?> </body> </html>

3 (1) Answer question (1) here. Write in the back page if necessary.

4 (2) [21 points] (a) Create a view s17t2a to provide film information that can be used as below. For example: MariaDB [sakila]> select * -> from s17t2a -> where category_id = 1 -> limit 5; category_id category film_id title rating actor_count Action 19 AMADEUS HOLY PG 6 1 Action 21 AMERICAN CIRCUS R 5 1 Action 29 ANTITRUST TOMATOES NC Action 38 ARK RIDGEMONT NC Action 56 BAREFOOT MANCHURIAN G rows in set (0.04 sec) (b) Using the view defined in (a), provide the SQL statement to show the number of films (that have five or more actors) in category 1 with each rating group. List only those rating groups with 7 or more films. For example: rating film_count G 14 PG-13 8 R 9 NC rows in set (0.02 sec)

5 (c) Define a stored function s17a to accept two arguments, category_id and min_actors. The function returns the number of films in the category with the id category_id and has at least min_actors number of actors. For example: MariaDB [sakila]> select s17a(1,9); s17a(1,9) This can be explained by: MariaDB [sakila]> select fc.film_id, count(distinct fa.actor_id) as count -> from film_category fc, film_actor fa -> where fc.film_id = fa.film_id -> and fc.category_id = 1 -> group by fc.film_id -> having count >= 9; film_id count

6 (3) [7 points] Use Armstrong s axioms and rules to prove that F = {BC->A, AC->D, BD->E} - BC->E (4) [14 points] True (T) or False (F) (a) The canonical cover of a relation may not be unique. (b) MySQL always enforces referential integrity once a foreign key constraint is defined for the relation. (c) Create an index for a table always improve the performance of querying the table. (d) The XPath expression //film[title] returns all <film> elements that have a title attribute in the document. (e) In MySQL, it is possible to define a trigger whenever a table is queried by a select statement. (f) Transactions in MySQL ensure the atomicity of the execution of the transaction bodies. (g) It is possible for a relation R(A,B,C,D,E) to have 32 superkeys.

7 (5) [8 points] Consider R(A,B,C,D,E) with the set of FDs: {A->C, AC->B, BC->D, E->B} R is decomposed into R1(A,B,C), R2(B,C,D) and R3(B,E). Is the decomposition lossless? Show your reasoning. Write in the back page if necessary.

8 (6) [25 points] Consider R(A,B,C,D,E,F) with F= {BC->D, C->A, AC->E, F->C, CE->F} (a) What are A+, B+, C+, D+, E+ and F+? (b) What are the candidate keys? Show all prime attributes. (c) Give a canonical cover of F. (d) What is the highest normal form (up to BCNF) of R and why? (e) If R is not in BCNF, can you provide a lossless FD preserving decomposition of R into BCNF relations? If yes, show such decomposition. If no, justify your answer.

CSCI 5333 DBMS Fall 2017 Final Examination. Last Name: First Name: Student Id:

CSCI 5333 DBMS Fall 2017 Final Examination Last Name: First Name: Student Id: Number: Time allowed: two hours. Total score: 100 points. This is a closed book examination but you can bring a cheat sheet.