Assignment – A
Q1: Suppose you are given a relation R= (A, B, C, D, E) with the following functional Dependencies: {BC! ADE, D! B}.
a. Find all candidate keys.
b. Identify the best normal form that R satisfies (1NF, 2NF, 3NF, or BCNF).
c. If the relation is not in BCNF, decompose it until it becomes BCNF. At each step, identify a new relation, decompose and re-compute the keys and the normal forms they satisfy.
Q2: Differentiate between Decision Support System (DSS) and Expert System. Also, write the main characteristics of both.
Q3: List principles of system design. Also, differentiate between Top-down and Bottom-up design with the help of a suitable example.
Q4: Write a short note on any three of the following.
a) Data Flow Diagram
b) Transaction Processing System
c) Role of a system analyst
d) WaterFall Model
e) E.R.Diagram
Q5: What are various types of maintenance?
Question 6: Define the term “Data Dictionary”. What is the need for a Data Dictionary?
Question 7: What is meant by “Feasibility Study”? Discuss its importance in system development.
Question 8: What do your understand by normalization. And also explain advantages and disadvantages of normalizations.
Case Study – 4
System Installation
A rug manufacturer and importer wanted to have his own computer and run applications away from the parent company’s mainframe. A computer consultant (with no knowledge of the rug business) did a feasibility study. He recommended a system with which he had design experience.
The firm leased the system and signed a contract with the consultant to do the installation and training. The consultants brought in two programmers and a data base specialist to convert the files and train personnel. For weeks, everyone was busy with what was bound to be a successful system.
As a first step, the company decided to compare the reports generated by the new system with those available from the main computer. The procedure was to run invoices first, followed by accounts receivable and payable. The first inventory reports seemed way out of line with reality. Both the format of the reports and the data were off. The few invoices sent out brought hostile complaints from customers who were overcharged for their orders. Further attempts to correct the errors only generated more inaccuracies. The company decided to go back to the old system and cancel the whole project.
The matter ended up in court with the consultant demanding the balance due him on the project. The company filed a counter suit claiming irreparable damage to the firm. An investigation discovered that despite management’s lack of experience with computers, they decided to convert three major applications at the same time. The employees, not having been forewarned of the conversion, panicked. Prior to the computer, they had undocumented methods of invoicing, keeping track of inventory, and billing procedures that the consultant never knew of or inquired about. To make matters worse, he did not even know that the parent company’s warehouse system had a terminal that used the mainframe to update inventory.
System testing was also a disaster. Only real data were used. The resulting output was so unwieldy that no one could audit or verify its accuracy until it was too late. With no interface between the system being tested and the mainframe, there was no way the files could be copied. The consultant decided to go ahead with the incoming data only and to worry later about copying the files on the mainframe.
Documentation and audit procedures were virtually nonexistent. No one seemed to know who changed what. There was no way of telling whether errors were caused by the software or by incorrectly entered data.
The contract was well written. It simply committed the consultant to install a computer system and the company to pay the consultant $75 per hour plus out-of-pocket expenses. The consultant never really knew what the company wanted, and the company had no work with the consultant. The employees stayed out of the ways, since they had not been consulted and were not knowledgeable about computers. The programmers, in their opinions, were simply obnoxious. Another consultant who came in to evaluate the mess thought the whole installation was primitive and lacked state-of-the-art software.
Questions
1. What went wrong in this case? Be specific.
2. Elaborate on the importance of a computer contract. What elements would you have emphasized in the contract? Why?
3. Does a contract save an installation from failure? In what way?
4. What testing procedure should have been followed? Explain.
Assignment – C
1. Requirement specification is carried out—
a) After requirements are determined
b) Before requirements are determined
c) Simultaneously with requirements determination
d) Independent of requirements determination
2. The role of a system analyst drawing up a requirements specification is similar to—
a) Architect designing a building
b) A structural engineer designing a building
c) A contractor constructing a building
d) The workers who construct a building
3. It is necessary to consult the following while drawing up requirement specification—
a) Only top managers
b) Only top and middle management
c) Only top, middle and operational managers
d) Top, middle and operational managers and also all who will use the system
4. In order to understand the working of an organization for which a computer based system is being designed, an analyst must—
a) Look at only current work and document flow in the organization
b) Discuss with top level and middle level management only
c) Interview top, middle, line managers and also clerks who will enter data and use the system
d) Only clerical and middle level staff who have long experience in the organization and will be users of the system
5. A feasibility study is carried out–
a) After final requirements specifications are drawn up
b) During the period when requirements specifications are drawn up
c) Before the final requirements specifications are drawn up
d) At any time
6. The main objective of feasibility study is—
a) to assess whether it is possible to meet the requirements specifications
b) to assess if it is possible to meet the requirements specified subject to constraints of budget, human resource and hardware
c) to assist the management in implementing the desired system
d) to remove bottlenecks in implementing the desired system
7. Hardware study is required—
a) To find out cost of computer system needed
b) To determine the type of computer system and software tools needed to meet the final system specification
c) To make sure that the system does not become obsolete
d) To find how to implement the system
8. Feasibility study is carried out by—
a) Managers of the organization
b) System analyst in consultation with managers of the organization
c) Users of the proposed system
d) Systems designers in consultation with the prospective users of the system
9. Initial requirements specification is—
a) Not changed till the end of the project
b) Continuously changed during project implementation
c) Only a rough indication of the requirement
d) Changed and finalized after feasibility study
10. The primary objective of system design is to—
a) Design the programs, databases and test plan
b) Design only user interfaces
c) Implement the system
d) Find out how the system will perform
11. System test plan is specified—
a) When the final specifications are drawn up
b) During feasibility study
c) During the requirements specifications stage
d) During system study stage
12. System design is carried out—
a) As soon as system requirements are determined
b) Whenever a system analyst feels it is urgent
c) After final system specifications are approved by the organization
d) Whenever the user management feels it should be done
13. The primary objective of system implementation is—
i) To build a system prototype
ii) To train users to operate the system
iii) To implement designed system using computers
iv) Write programs, create databases and test with live data
a) i, iii
b) i, ii, iii
c) ii, iii
d) ii, iv
14. The main objective of system evaluation is—
a) To see whether the system met specification
b) To improve the system based on operational experience for a period
c) To remove bugs in the programs
d) To asses the efficiency of the system
15. A data dictionary has consolidated list of data contained in —
(i) Data flows
(ii) Data stores
(iii) Data outputs
(iv) processes
a) (i) and (iii)
b) (i) and (ii)
c) (ii) and (iv)
d) (i) and (iv)
16. System analysts have to interact with—
i) Managers of organizations
ii) Users in the organization
iii) Programming team
iv) Data entry operator
a) iii and iv
b) i, ii and iii
c) ii, iii and iv
d) ii and iii
17. Systems analyst should use software tools in their work as—
a) All analysts use them
b) They assist in systematic design of systems
c) They are inexpensive
d) They are easily available
18. During feasibility analysis it is necessary to examine several alternative solutions because —
(i) A comparison of alternatives will lead to a cost-effective solution
(ii) A pre-conceived single solution may turn out to be unimplementable
(iii) It is always good to examine alternatives
(iv) Management normally looks at alternatives
a) i and iii
b) i and iv
c) i and ii
d) ii and iv
19. The primary responsibility of a systems analyst is to—
a) Specify an information system which meets the requirements of an organization
b) Write programs to meet specifications
c) Maintain the system
d) Meet managers of the organization regularly
20. The responsibilities of a system analyst include—
i) Defining and prioritizing information requirement of an organization
ii) Gathering data, facts and opinions of users in an organization
iii) Drawing up specifications of the system for an organization
iv) Designing and evaluating the system
a) i and ii
b) i, ii and iv
c) i, ii, iii and iv
d) i, ii and iii
21. The intangible benefits in the following list are —
(i) Savings due to reducing investment
(ii) Savings due to sending bills faster and consequent early collection
(iii) Providing better service to the customers
(iv) Improving quality of company’s products
a) i and ii
b) ii and iii
c) iii and iv
d) i and iii
22. In a DFD external entities are represented by a—
a) Rectangle
b) Ellipse
c) Diamond shaped box
d) Circle
23. A data flow can—
a) Only emanate from an external entity
b) Only terminate in an external entity
c) May emanate and terminate in an external entity
d) May either emanate or terminate in an external entity but not both
24. The most important attribute of a systems analyst is—
a) Excellent programming skills
b) Very good hardware designing skills
c) Very good technical management skills
d) Very good writing skills
25. Data inputs which required coding are—
a) Fields which specify prices
b) Key fields
c) Name fields such as product name
d) Fields which are of variable length
26. An entity is—
a) A collection of items in an application
b) A distinct real world item in an application
c) An inanimate object in an application
d) A data structure
27. A relationship is—
a) An item in an application
b) A meaningful dependency between entities
c) A collection of related entities
d) Related data
28. A cost-benefit analysis is performed to assess—
a) Economic feasibility
b) Operational feasibility
c) Technical feasibility
d) All of the above
29. Among the attributes of a systems analyst the following are most important—
i) Knowledge of computer systems and currently available hardware
ii) Good interpersonal relations
iii) Broad knowledge about various organizations
iv) Very good accountancy knowledge
a) i, iii and iv
b) i and iii
c) i, ii and iv
d) i, ii and iii
30. A rectangle in a DFD represents—
a) A process
b) A data store
c) An external entity
d) An input unit
31. The entity set is a—
a) Set of entities
b) Collection of different entities
c) Collection of related entities
d) Collection of similar entities
32. Attributes are—
(i) Properties of relationship
(ii) Attributed to entities
(iii) Properties of members of an entity set
a) i
b) i and ii
c) i and iii
d) iii
33. Rows of a relation are called—
a) Tuples
b) A relation row
c) A data structure
d) An entity
34. If an entity appears in N relationships then it is—
a) A 1:1 relationship
b) A 1: N relationship
c) A N: 1 relationship
d) A N: M relationship
35. Normalization is a process of restructuring a relation to—
a) Minimize duplication of data in a database
b) Maximize duplication of data to ensure reliability
c) Make it of uniform size
d) Allow addition of data
36. Normalization of database is essential to—
(i) Avoid accidental deletion of required data when some data is deleted
(ii) Eliminate inconsistencies when a data item is modified in the database
(iii) Allows storage of data in a computer’s disk
(iv) Use a database management system
a) i and iii
b) i and ii
c) ii and iii
d) ii and iv
37. A relation is said to be in 1NF if—
a) There is no duplication of data
b) There are no composite attributes in the relation
c) There are only a few composite attributes
d) All attributes are of uniform type
38. By redundancy in a file based system we mean that—
a) Unnecessary data is stored
b) Same data is duplicated in many files
c) Data is unavailable
d) Files have redundant data
39. Data integrity in a file based system may be lost because—
a) The same variable may have different values in different files
b) Files are duplicated
c) Unnecessary data is stored in files
d) Redundant data is stored in files
40. Given the following relation—vendor order (vendor no, order no, vendor name, qty supplied, price/unit) it is not in 2 NF because—-
a) It is not in 1 NF
b) It has a composite key
c) Non-key attribute vendor name is dependent on vendor no. which is one part of the composite key
d) Qty supplied and price/unit are dependent
Reviews
There are no reviews yet.