1. G063 - Testing

2. Learning Objectives: By the end of this topic you should be able to:
explain the importance of testing and test plans
describe the purpose of test data

3. Testing IT systems can be complex and error prone
it’s important to identify errors in the system
before it is put into use,
errors are likely to cost time and/or money
in safety-critical systems errors could be life-threatening.

4. Testing: Exam questions
Try to formulate answers to the following questions
Use the mark schemes on the VLE to check:

5. Why is Testing important?
to make sure the system produces expected results
to identify errors
any faults can be rectified
to make sure the customer is satisfied
system does what the customer wanted
to get paid!
to give confidence to the users of the system
by proving that it can cope with all eventualities

6. The process of testing involves:
plan the tests
select data that will be used to test the system
run the tests
identify faults
correct the faults
user testing

7. Test Plans A test plan is: a list of tests to be performed,
an indication of type of test,
normal, erroneous, extreme
valid, invalid, extreme
a statement of the data to be used for the test,
a list of expected results,

8. Test Plans

9. Why is a Test Plan required?
so you know what to test
so you know what has been tested
to ensure that everything has been tested
to make sure the tests can be reproduced
to know if the actual results meet expected results

10. 3 types of Test Data used:
Normal or expected data
to check that the system works as expected
Erroneous data
invalid data that might be entered by mistake
Extreme data
data at the lower and upper extremes of the range

11. Why is a Test Plan required?
to test the system’s performance against the design spec.
to describe each item that needs to be tested
so you know what to test
so you know what has been tested
to ensure that everything has been tested
to specify how each test will be carried out
by identifying input values and showing expected output
to know if the actual results meet expected results
allows discrepancies to be identified
to make sure the tests can be reproduced