INF3707
EXAM PACK
,UNIVERSITY EXAMINATIONS
JUNE / JULY 2021
INF3707
DATABASE DESIGN AND IMPLEMENTATION
Date: 05 July 2021
Duration: 2 hours
Total marks: 100
Examiners:
First: Dr B. Chipangura
Second: Dr L. Motsi
External: Dr P. Nkomo
This is a closed book examination.
Instructions to students
1. Unisa examination policies apply.
2. Answer all questions.
3. Study the tables and data in Annexure A.
4. The marks for each question are given in brackets next to the question.
5. Please answer the questions in order. If you want to do a question later, leave a blank
space.
6. Pocket calculators are not allowed.
7. Pledge that you have neither given nor received aid on this examination (You must respond
to this pledge when submitting your assignment.)
8. After writing the exam, upload your answer sheet in PDF format on myUnisa as per
instructions provided to you in Exam Tutorial letter. Do not add any other form of
protection on your document. Incorrect file formats or unreadable files will be assigned a
zero mark.
9. Students who do not submit their answer sheets within the scheduled session time will be
marked as absent. Those who could not participate in the examination must formally apply
for an aegrotat opportunity. This rule also applies to students who may be affected by load
shedding. You should supply sufficient evidence in an application for an aegrotat due to load
shedding. Note that supplementary students do not qualify for an aegrotat regardless of the
circumstances.
10. You are not allowed to copy any text from the textbook or slides; other students’ notes or
answers; templates, memos or example answers from any previous assignments, online
tutors, the internet, or any other sources. All questions must be answered in your own,
original words. All scripts will be put through a plagiarism checking tool. Cases, where
copying and pasting, patchwriting, plagiarism, collaboration or other authenticity issues are
suspected, will receive a zero mark and the cases will be reported to the Student Disciplinary
Section in DSAA for disciplinary action.
[Turn over]
, 2 INF3720
OCT/NOV
Question 1 10 marks
1.1 Which Oracle Database management system is prescribed for this module? (2 marks)
1.2 How do you login as the system administrator on the Oracle SQL*plus interface? Provide the code.
(2 marks)
1.3 After you have successfully installed Oracle database, how do you open the pluggable databases so
that they can automatically open? (4 marks)
1.4 By default, Oracle pluggable databases remain closed and must be opened manually or set to
automatically open. Which Oracle 18c XE service must you configure to do that? (2 marks)
Question 2 40 marks
Assume that a table named MyTable exist in your database. MyTable has five columns Col#, Col1, Col2,
Col3 and Col4.
NAME NULL TYPE
-------- ------ ---------
Col# NOT NULL Number Primary key
Col1 NOT NULL VARCHAR2(2)
Col2 NOT NULL VARCHAR2(10)
Col3 NOT NULL VARCHAR2(10)
Col4 NOT NULL VARCHAR2(10)
2.1 Write an SQL statement that enables you to view the structure of MyTable. (2 marks)
2.2 Write an SQL statement that allows you to see the data contained in all the columns of MyTable.
(3 marks)
2.3 MyTable contains some columns that are marked as unused. Write an SQL code that drops all the
columns marked as unused. (4 marks)
2.4 All the data entered into MyTable is not correct. Write an SQL code that deletes the data from the
table but leaving it intact. (3 marks)
2.5 You realised that Col1 and Col4 are too small to accommodate large variables, write an SQL code
that increases the size of Col1 from 2 to 17 and Col4 from 10 to 25. (5 marks)
2.6 Insert data into three columns of MyTable, by populating Col1, Col2 and Col4 with values A, B and
D in that order. Do not insert any data into Col3, store a null value. (5 marks)
2.7 If the primary key of this table was created with the following statement:
Col# Number GENERATED AS IDENTITY PRIMARY KEY;
What output do you expect after inserting the following data into MyTable? Explain your answer.
[Turn over]