CS2255 Database Management Systems question paper - Nov/Dec 2014 / Anna University Previous Year 2014 Exam Questions / Anna University Previous Year 2014 Computer Science and Information Technology Question Papers / CS 2255/CS 46/CS 1254/080250009/10144 CS 406 — Database Management Systems Question with Answers
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Question
Paper Code : 91347
B.E./B.Tech.
DEGREE EXAMINATION, NOVEMBER/DECEMBER 2014.
Fourth
Semester
Computer
Science and Engineering
CS 2255/CS
46/CS 1254/080250009/10144 CS 406 — DATABASE MANAGEMENT SYSTEMS
(Common
to Information Technology)
(Regulation
2008/2010)
(Common
to PTCS 2255/10144 CS 406 – Database Management Systems for
B.E.
(Part-Time) Third Semester – Computer Science and Engineering
Regulation
2009/2010)
Time :
Three hours
Maximum :
100 marks
Answer ALL questions.
PART A —
(10 × 2 = 20 marks)
1. What is physical, logical and view level data
abstraction?
3. Explain the use of assignment operator in
relational algebra with an example.
4. What is the use of UNIQUE statement?
5. Define trivial functional dependency.
6. What is meant by referential integrity?
7. What is a cascading update?
8. What are the disadvantages of not controlling
concurrency?
9. What is a heap file? How pages are organized in a
heap file?
10. What is a catalog?
PART B —
(5 × 16 = 80 marks)
11. (a) (i) Why would you choose
a database system instead of simply
storing data in operating system files? When would it make sense not to use a
database system?
(ii) Explain the difference
between logical and physical data independence. (8 + 8)
Or
(b) Notown Records has decided to
store information about musicians who perform in its albums (as well as other
company data) in a database. The company has wisely chosen to hire you as a
database designer.
Each musician that records at
Notown has an SSN, a name, an address, and a phone number. Poorly paid
musicians often share the same address, and no address has more than one phone.
Each instrument used in songs
recorded at Notown has a unique identification number, a name (e.g., guitar,
synthesizer, flute) and a musical key (e.g., C, B-flat, E-flat).
Each
album that is recorded on the Notown label has a title, a copyright date, a
format (e.g., CD or MC), and an album identifier.
Each
song recorded at Notown has a title and an author.
Each
musician may play several instruments, and a given instrument may be played by
several musicians.
Each
album has a number of songs on it, but no song may appear on more than one
album.
Each
song is performed by one or more musicians, and a musician
may perform a number of songs.
Each
album has exactly one musician who acts as its producer. A musician may produce several albums, of
course.
Design a conceptual schema for Notown
and draw an ER schema for your schema. The preceding information describes the
situation that the Notown database must model. Be sure to indicate all key and
cardinality constraints and any assumptions that you make. Identify any
constraints that you are unable to capture in the ER diagram and briefly
explain why you could not express them.
12. (a) Consider the following
schema;
Supplier(sid: integer, sname:
string, address: string)
Parts(pid: integer, pname:
string, color: string)
Catalog (sid: integer, pid: integer,
cost: real)
The key fields are underlined,
and the domain of each field is listed after the field name. Therefore sid is
the key for suppliers, pid is the key for parts, and sid and pid together form
the key for catalog. The catalog relation has the prices charged for parts by
suppliers. Write the following queries in relational algebra.
(i) Find the sids of suppliers who supply a red part or green
part.
(ii) Find
the sids of suppliers who supply every part.
(iii) Find
the sids of suppliers who supply every red part or supply every green part.
Or
(b) Briefly explain about
fundamental, and additional operations in SQL with example.
13. (a) (i) What are the threedata anomalies that are likely to occur as a result of data redundancy? Can
data redundancy be completely eliminated in database approach? Why or why not? (6)
Or
(b) (i) Define the domain
relational calculus. (6)
(ii) Given R(A,B,C,D,E) with the
set of FDs, F(ABàCD,
ABCàE, CàA).
(1) Find any two candidate keys
of R.
(2) What is the normal form of R?
Justify. (10)
14. (a) (i) Define and
differentiate between Deadlock prevention, Deadlock detection, and Deadlock
avoidance. (6)
(ii) Explain different locking
mechanism used in lock based concurrency control. (10)
Or
(b) (i) What are the deferred
modification and immediate modification technique for recovery? How does
recovery takes place in case of a failure in these techniques? (8)
(ii) Explain timestamp based
concurrency control with and without Thomas write rule. Give example. (8)
15. (a) (i) Explain the
differences between Hash indexes and B+ tree indexes. In particular, discuss
how equality and range searches work, using an example. (6)
(ii) Explain the structure of B+
tree. How to process queries in B+ tree? (10)
Or
(b) What is RAID? Briefly explain
different levels of RAID. Discuss the factors to be considered in choosing a
RAID level. (16)
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