NATIONAL OPEN UNIVERSITY OF NIGERIA

UNIVERSITY VILLAGE, PLOT 91, CASDASTRAL ZONE, NNAMDI AZIKIWE EXPRESS WAY, JABI, ABUJA.
FACULTY OF SCIENCES
JUNE/JULY 2018 EXAMINATION

CIT427: Database System and Management – (2 Credits)

 Answer Question 1 and three other questions in 2 Hours.

Total of 70, Question 1 is 25 marks and others 15 marks each

1a (i) Define the term ‘database management system.’

     (ii) List the common categories of database management systems.(4 marks)

b (i)Describe a data dictionary.

    (ii) State the data structures required for physical systemimplementation (4 marks)

c (i) Within the context of entity representation, what is an attribute?

    (ii) State the specific role of the project operation. (3 marks)

d (i) Identify the forms of accessibility, addressability.

 (ii) Briefly describe the concept of file organization  (3 marks)

e Explain the notion of latency.(3 marks)

(f) List 10 examples of secondary storage (4 marks)

(g)Highlight the Advantages and Disadvantages of Web Services over other technologies

(4 marks)

                                                                                                                   (25 Marks)

2a Identify the relationship between the XML pointer language andthe XML linking language.(5 marks)

 b Highlight the Advantages and Disadvantages of Web Services over other technologies

(5 marks)

   (c) Identify the difference between the Read/Write and Read onlystorage.(5 marks)

(15 Marks)

3a List at least four structural components of SQL. (8 marks)

  b State the specific roles of a data definition language.(4 marks)

  c Describe the concept of an interactive data manipulationlanguage (3 marks)

(15 Marks)

4a Explain the concept of an entity set.(3 marks)
 b State the link between entities and programming languages.(3 marks)
 c Within the context of entity representation, what is an attribute? (3 marks)

(d) Describe the Slow write, fast read storage.(3 marks)

 ( e) State the Entity-Relationship scheme for defining constraints. (3 marks)

                                                                                                                        (15 Marks)

5a Describe object-based logical models. (6 marks)
 b. List the common types of object-based logical models.(3 marks)
 c. Explain the concept of entity-relationship models.(3 marks)
 d. State the essential elements of an entity-relationship diagram(3 marks)

(15 Marks)