UNIVERSITY EXAMINATIONS: 2010/2011
THIRD YEAR STAGE EXAMINATION FOR THE DEGREE OF BACHELOR OF
SCIENCE IN INFORMATION TECHNOLOGY
BIT 4306 DISTRIBUTED DATABASES
DATE: JUNE 2011 TIME: 2 HOURS
INSTRUCTIONS: Answer question ONE and any other TWO questions
Question One
a)Differentiate between the following terms:
i) Distributed processing vs Cooperative processing (4 Marks)
ii) Data Warehouse vs Distributed database (4 Marks)
iii)Distributed processing vs Database link (4 Marks)
b)Explain the two major concepts used to facilitate connectivity between Oracle DBMS and a non
Oracle DBMS (8 Marks)
c)Explain how shared links differ from standard database links (6 Marks)
d)In a distributed database system, you must carefully plan the user accounts and roles that are necessary to
support applications using the system. Examine the main factors you need to consider when setting up user
accounts and roles (6 Marks)
Question Two
a)Briefly describe the different types of users of database links (6 Marks)
b)Discuss the different character sets as used in different database environments (9 Marks)
c)Using an example explain how you would determine whether global naming on a database is enforced
(5 Marks)
Question Three
a)Using an appropriate example, explain why a database link does not always have the same name as the
global database name of the remote database that it references. (5 Marks)
b)As a database Administrator, discuss any FIVE security options you will consider in a distributed
database environment (10 Marks)
c)
i) Explain the concept of client server database architecture (1 Mark)
ii) Explain the two ways used to access information in a distributed database environment
based on client server architecture (4 Marks)
Question Four
a) Show how the Oracle Database uses the global database name to name the schema objects
globally (6 Marks)
b) i) Define the term Transaction (2 Marks)
ii) Using examples differentiate between a remote transaction and a distributed transaction
(2 Marks)
c) “A database link connection is one-way”. Give reasons supporting or disapproving the
statement (4 Marks)
d) i) Explain the main parts of a synonym (5 Marks)
iii)Write a statement that will define a synonym for the scott.emp table stored in the hq
database (1 Mark)
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) There are two types of permissible operations in distributed transactions: DML and DDL
Transactions as well as Transaction Control Statements. Outline any two operations supported
by each. (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)
