Systems Analysis

Question 1

What are the stages of the cycle in order

Answer 1

Feasibility study, investigation, analysis, documentation, testing, design, implementation, changeover, maintenance/ backup

Question 2

Describe the benefits and drawbacks of the agile approach

Answer 2

Pros:

• Easier to add features that keep upto date
• allows for changes to be made after initial planning

Cons:

• documentation is neglected
• as the project doesn’t gave a definitive plan, the final product can be very different

Question 3

Describe the benefits and drawbacks of the waterfall approach

Answer 3

Pros:
Requires less communication between client and developer
Cons:
-cannot go back and make changes
-very bad at reacting to changing requirements

Question 4

List and explain the different types of feasibility that is including the study

Answer 4

Technical feasibility: will the proposed system meet its objectives? Does the technology exist?

Social feasibility:, the effects on the employees and customers of the proposed system

Legal feasibility: are there any legal constraints thet would probibit parts of the system?

Question 5

Why is feasibility study important?,

Answer 5

It is important as it shows whether or not the proposed system is worth continuing with

Question 6

What are the 4 different methods of investigation

Answer 6

Observation
Questionnaire
Document collection
Interviews

Question 7

What are the benefits and drawbacks of observation

Answer 7

Benefits:
Can see what’s happening
Pics up parts of the system that isn’t immediately obvious

Drawbacks:
Time consuming
Staff feel watched so behave differently

Question 8

What are the benefits and drawbacks of a questionnaire

Answer 8

Benefits:
Cheap for a large number of people
Drawbacks:
Not everyone will complete it

Question 9

What are the benefits and drawbacks of document collection

Answer 9

Benefits:
Inexpensive
Drawbacks:
Files can contain sensitive information

Question 10

What are the benefits and drawbacks of interviews

Answer 10

Benefits:
Gathers large amounts of detailed information

Drawbacks:
Time consuming to carry out
Difficult to analyse large amounts of info

Question 11

Hoe can a data flow diagram help an analyst

Answer 11

A data flow diagram visualises the process making it more clear to the analyser

Question 12

What are the four different types of symbols used in dfd

Answer 12

Entity (box) - a data source of destination
Process (box with curved edges) - an operation performed on the data
Data store (rectangle with one missing side) - a file
Data flow (arrow) - the data and its direction of flow

Question 13

What are the details usually provided in user documentation

Answer 13

• step by step “getting started” guides
• installation guide
• user guide focusing on user tasks
• reference manual
• glossary
• error messages + troubleshooting guide

Question 14

What are the details usually provided in technical documentation

Answer 14

• the data structures
• algorithm designs
• variable lists
• data dictionary
• entity relationship diagrams
• design documents

Question 15

Describe alpha testing

Answer 15

Conducted in-house by developers, occurs before the customer agrees to accept the final program.

Question 16

Describe beta testing

Answer 16

conducted after alpha testing and later on in the software dev cycle by a select few people who report bugs to the developers to fix

Question 17

Describe end user (acceptance) testing

Answer 17

Where the software is tested by the intended audience

Question 18

What do the designers need to create during the design stage?,

Answer 18

Design the data structures

Files/database structures

Algorithms

User interface designs

Design the test data to be used

Question 19

What are the 4 types of changeover methods

Answer 19

Direct changeover

Pilot changeover

Parcel changeover

Phased conversion

Question 20

Explain direct changeover

Answer 20

Sudden changeover in New system

Question 21

Explain pilot changeover

Answer 21

Used by part of the organisation

Question 22

Explain parallel changeover

Answer 22

Both old and new systems running at the same time

Question 23

Explain phased changeover

Answer 23

Phasing in parts of the system

Question 24

List the 3 types of maintenance

Answer 24

Perfective maintenance

Adaptive maintenance

Corrective maintenance

Question 25

Describe perfective maintenance

Answer 25

This type of maintenance improves the current system being used

Question 26

Describe adaptive maintenance

Answer 26

Current system being used is changed to suit certain requirements

Question 27

Describe Corrective maintenance

Answer 27

Involves fixing errors found in the current system while being used

Question 28

Advantages of direct changeover

Answer 28

Fan be cheaper to implement

Can be the least disruptive if implemented well

Question 29

Advantages of pilot

Answer 29

If something goes wrong only a small part of the organisation is affected

All staff can focus on one area to solve problems

Question 30

Advantages of phased changeover

Answer 30

Could be direct or parallel

Question 31

What does the phased changeover method involve

Answer 31

Used with larger systems that can be broken down into individual modules that can be implemented separately at different times

Question 32

What does pilot changeover involve

Answer 32

A department is selected in the organisation and they run the new system exile the remainder continue either the established procedures

Question 33

Drawbacks of direct changeover

Answer 33

If the new system fails organisation will have no system which is costly and dangerous

May not work well until staff are fully used to using it

Question 34

Drawbacks of pilot changeover

Answer 34

Slower to get new system up and running compared to other methods

Might cause problems jn the changeover period when they need to communicate with eachother and have different systems

Question 35

Drawbacks of phased changeover

Answer 35

May be compatibility issues between the new and the existing modules