UCI ICS 184 - Midterm Exam (11 pages)

Previewing pages 1, 2, 3, 4 of 11 page document View the full content.
View Full Document

Midterm Exam



Previewing pages 1, 2, 3, 4 of actual document.

View the full content.
View Full Document
View Full Document

Midterm Exam

131 views


Pages:
11
School:
University of California, Irvine
Course:
Ics 184 - Course Reference

Unformatted text preview:

Midterm Exam Fall 2006 Max Points 100 Please read the instructions carefully Instructions Total time for the exam is 75 minutes No extra time will be awarded so budget your time accordingly The exam is closed books and closed notes The exam is divided into 2 sections 8 multiple choice questions a correct answer will get you 5 points an incorrect answer and answers left blank will get you 0 points 4 other questions totaling 60 points If you find ambiguities in a question or in the schema write down the interpretation you are taking and then answer the question based on your interpretation This exam contains 12 pages of which pages 11 and 12 are blank You can use them as scratch paper NAME ALIAS Part Points I II Total 40 60 100 Score Question 1 Which of the following statements are true 1 Each superkey is a superset of some candidate key 2 Each primary key is also a candidate key but there may be candidate keys that are not primary keys a b c d only 1 is true only 2 is true both 1 and 2 are true neither 1 nor 2 are true Answer The following two questions refer to the relational scheme R A B C D E F G H and the following functional dependencies over R A BCD AD E EFG H F GH Question 2 Based on the functional dependencies there is one key for R What is it AF Question 3 One of the four functional dependencies can be removed without altering the key Which one EFG H C Question 4 Suppose that two relations R A B and S A B have exactly the same schema Consider the following equalities in relational algebra I R S R R S II R S S S R III R S R NATURAL JOIN S IV R S R x S Which of the equalities hold in relational algebra A B C D I only I and II only I II and III I II III and IV ANSWER c Question 5 Which of the following statements are true about weak entity sets 1 A weak entity set cannot have a primary key 2 A weak entity set must have a local attribute in primary key 3 A weak entity must borrow an attribute from another entity set to form a primary key a b c d None of them 1



View Full Document

Access the best Study Guides, Lecture Notes and Practice Exams

Loading Unlocking...
Login

Join to view Midterm Exam and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Midterm Exam and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?