UNIVERSITY EXAMINATIONS: 2016/2017
EXAMINATION FOR THE DEGREE OF BACHELOR OF SCIENCE IN INFORMATION
TECHNOLOGY/ BACHELOR OF BUSINESS INFORMATION TECHNOLOGY
BIT3202A BBIT304 DISTRIBUTED DATABASES ADVANCED DATABASE SYSTEMS
FULL TIME/PART TIME/DISTANCE LEARNING
DATE: AUGUST, 2017 TIME: 2 HOURS
INSTRUCTIONS: Answer Question One & ANY OTHER TWO questions.
QUESTION ONE
a) Discuss how the concepts of Distributed processing and Cooperative processing are applied in
Distributed databases. (8 Marks)
b) Explain how connectivity between Oracle DBMS and a non Oracle DBMS can be facilitated
(8 Marks)
c) Examine the different ways in which high reliability is achieved in distributed databases
(8 Marks)
d) Explain any three complicating factors associated with distributed database
(6 Marks)
QUESTION TWO
a) Examine any four applications that use distributed databases concepts (4 Marks)
b) What benefits are provided by views in databases? (6 Marks)
c) Query processing is a three step process that transforms a high-level query of
relationalcalculus/SQL into an equivalent and more efficient lower-level query of relational
algebra. Describe the activities involved in Query processing (6 Marks)
d) Explain the properties of a transaction (4 Marks)
QUESTION THREE
a) Briefly explain how the Two-Phase Commit Mechanism in distributed databases ensures data
integrity (5Marks)
b) Do you think the following are distributed database management systems or not?
i) Distributed Processing (2 Marks)
ii) Parallel DBMS (2 Marks)
c) Using a relevant example explain the concept of a Remote Procedure Calls (RPCs) in distributed
databases (6Marks)
d) Briefly explain how Distributed Query Optimization is achieved in oracle databases
(5 Marks)
QUESTION FOUR
a) Discuss how the following strategies are used in replication
i) Centralized (3 Marks)
ii) Partitioned (3 Marks)
iii) Complete Replication (3 Marks)
iv) Selective Replication (3 Marks)
a) Explain the architecture that is the most preferred for distributed databases
(4Marks)
b) Using SQL show how Views can be used to create location transparency in a distributed database
(4 Marks)
QUESTION FIVE
a) Elaborate on the following distributed query optimization methods
i) Collocated Inline Views (2 Marks)
ii) Using Cost-Based Optimization (2 Marks)
b) Explain using examples any two operations supported by each of DML and DDL (4 Marks)
c) Describe how the global coordinator controls distributed transactions in a distributed database,
(6 Marks)
d) Outline the three ways in which Distributed transactions can become in-doubt
(6 Marks)
