Question

Hi I need help on this question what are the software testing techniques. Also, for each of the techniques you discussed explain the practical uses and implications for different software development projects and situation.

Answer 1

5 important software testing techniques-

Boundary Value Analysis (BVA)

Equivalence Class Partitioning

Decision Table based testing.

State Transition

Error Guessing

Boundary Value Analysis (BVA)

Boundary value analysis is based on testing at the boundaries between partitions. It includes maximum, minimum, inside or outside boundaries, typical values and error values.

It is generally seen that a large number of errors occur at the boundaries of the defined input values rather than the center. It is also known as BVA and gives a selection of test cases which exercise bounding values.

This test case design technique complements equivalence partitioning. This software testing technique base on the principle that, if a system works well for these particular values then it will work perfectly well for all values which comes between the two boundary values.

Example:

Input condition is valid between 1 to 10

Boundary values 0,1,2 and 9,10,11

Equivalence Class Partitioning

Equivalent Class Partitioning allows you to divide set of test condition into a partition which should be considered the same. This software testing method divides the input domain of a program into classes of data from which test cases should be designed.

The concept behind this technique is that test case of a representative value of each class is equal to a test of any other value of the same class. It allows you to Identify valid as well as invalid equivalence classes.

Example:

Input conditions are valid between

1 to 10 and 20 to 30

Hence there are three equivalence classes

--- to 0 (invalid)

1 to 10 (valid)

11 to 19 (invalid)

20 to 30 (valid)

31 to --- (invalid)

You select values from each class, i.e.,

-2, 3, 15, 25, 45

Decision Table Based Testing.

A decision table is also known as to Cause-Effect table. This software testing technique is used for functions which respond to a combination of inputs or events. For example, a submit button should be enabled if the user has entered all required fields.

The first task is to identify functionalities where the output depends on a combination of inputs. If there are large input set of combinations, then divide it into smaller subsets which are helpful for managing a decision table.

For every function, you need to create a table and list down all types of combinations of inputs and its respective outputs. This helps to identify a condition that is overlooked by the tester.

Following are steps to create a decision table:

Enlist the inputs in rows

Enter all the rules in the column

Fill the table with the different combination of inputs

In the last row, note down the output against the input combination.

State Transition

In State Transition technique changes in input conditions change the state of the Application Under Test (AUT). This testing technique allows the tester to test the behavior of an AUT. The tester can perform this action by entering various input conditions in a sequence. In State transition technique, the testing team provides positive as well as negative input test values for evaluating the system behavior.

Error Guessing

Error guessing is a software testing technique which is based on guessing the error which can prevail in the code. It is an experience-based technique where the test analyst uses his/her or experience to guess the problematic part of the testing application.

The technique counts a list of possible errors or error-prone situations. Then tester writes a test case to expose those errors. To design test cases based on this software testing technique, the analyst can use the past experiences to identify the conditions.

Guidelines for Error Guessing:

The test should use the previous experience of testing similar applications

Understanding of the system under test

Knowledge of typical implementation errors

Remember previously troubled areas

Evaluate Historical data & Test results.