UNIVERSITY EXAMINATIONS: 2016/2017
EXAMINATION FOR DEGREE OF BACHELOR SCIENCE INFORMATION
TECHNOLOGY/BACHELOR OF BUSINESS INFORMATION TECHNOLOGY
BIT1207A BBIT 107 PRINCIPLES OF DATABASE DESIGN
MODE: DISTANCE LEARNING
JULY.2017 DURATION: 2 HOURS
INSTRUCTIONS: Answer question ONE and any other TWO questions
QUESTION ONE [30 MARKS]
a) Discuss the activities involved during user training at the implementation stage of the
b) Describe the THREE weaknesses of file based approach.
c) Describe the THREE strengths of database approach.
d) Define the concept of database anomaly
e) Discuss the database architecture according to ANSI PARC.
f) State and explain any FIVE database security threats.
g) There are two approaches are used to store a relation in a distributed database systemreplication and fragment. Differentiate between these two approaches.
h) Describe the activities involved in conceptual database design.
QUESTION TWO [20 MARKS]
a) Describe the motivation behind data independence
a) Discuss the following problems associated with concurrently executing transactions in a
i. Buried update problem
ii. Uncommitted dependency problem
iii. Non-repeatable read
iv. Phantom read.
b) Differentiate between DDL statements and DML statements in SQL
c) Describe the FIVE software components of a DBMS
QUESTION THREE [20 MARKS]
a) Describe the stages of database development life cycle (DBDLC).
b) Differentiate between the following types of attributes
i. Non-key attribute and key attribute
ii. Multivalued attribute and single-valued attribute
iii. Surrogate key and primary key
c) Normalize the following database to third normal form and draw the logical data model.
QUESTION FOUR [20 MARKS]
b) In a hospital management system, each doctor must treat one or more patients. Each patient
must be treated by a doctor. A patient may take one or more medications but each medication
is given to one patient. Construct a logical data model for this case using crow’s foot
notation, complete with cardinalities and optionalities.
c) Discuss any FIVE components of a database manager.
d) Define the concept of database integrity.
e) Discuss THREE applications of a distributed database.
f) Discuss the FOUR key properties of a database transaction.
QUESTION FIVE [20 MARKS]
a) Study the database table named EMPLOYEE below and answer the questions that follow:
Write appropriate SQL statements for each of the cases below:
i. Display the mean age of all the male guests
ii. Remove all guests from the EMPLOYEE table if their surnames end with letter ‘O’.
b) Discuss the following database models, citing circumstances under which each may be used.
i. Network model
ii. Hierarchical model
iii. Relational model
c) Describe TWO advantages and TWO disadvantages of a hierarchical database model.
d) Discuss any FOUR database maintenance activities performed on an existing database. [4 Marks]