Download JNTUH MCA 5th Sem R15 2018 June-July 825AC Distributed Databases Question Paper

Download JNTUH (Jawaharlal nehru technological university) MCA (Master of Computer Applications) 5th Sem (Fifth Semester) Regulation-R15 2018 June-July 825AC Distributed Databases Previous Question Paper

R15

Code No: 825AC

JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD

MCA V Semester Examinations, June/July - 2018

DISTRIBUTED DATABASES



Time: 3 Hours















Max. Marks: 75


Note: This question paper contains two parts A and B.

Part A is compulsory which carries 25 marks. Answer all questions in Part A. Part B
consists of 5 Units. Answer any one full question from each unit. Each question carries 10
marks and may have a, b, c as sub questions.



PART - A



















5 ? 5 Marks = 25

1.a) What are the advantages of a distributed database management system over a

centralized DBMS?















[5]

b) Give the comparison of global queries and fragmented queries.





[5]

c) Discuss the ways in which the concurrency control approaches can be classified. [5]
d) Define reliability. What are the types of failures in distributed DBMS?



[5]

e) Differentiate between DDBMS and MDBMS.









[5]



PART - B

















5 ? 10 Marks = 50

2.

Why is data replication useful in Distributed Database and what typical units of data are
replicated?

















[10]

OR

3.

Distributed databases can be fragmented in many ways. Define the term fragmentation and
explain using real world examples any three types of fragmentation that can be carried out.






















[10]


4.

What is query optimization? Give the framework for query optimization in distributed
environment.

















[10]

OR

5.

List steps of query decomposition and explain any one from that.



[10]


6.

Consider a failure that occurs during 2PC for a transaction. For each possible failure,
explain how 2PC ensures transaction atomicity despite the failure?



[10]

OR

7.

Explain briefly about timestamp-based concurrency algorithms.





[10]


8.

Define a catalog. How is it maintained in distributed databases?





[10]

OR

9.

Describe the role of check points and cold restart mechanisms in dealing with
inconsistencies in transactions.













[10]



10.

Explain briefly about architectural issues in distributed object DBMS.



[10]

OR

11.

Give objective of query processing in view of distributed database.



[10]



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