Functional Testing Interview Preparation Guide

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Functional testing verifies that the end user gets what he wants from the application. It involves testing to ensure that the tasks or the steps required completing functionality works well. Functional testing involves testing of functional requirements as per the specification.

System testing has classifications like functional and non functional testing. Hence the functional testing is a part of system testing.

System testing allows the testers to test the typical end product. Every single module, interface and every minute detail are needed to be tested in system testing.

Functional testing is aimed at testing the functionalities of the product being tested. These functionalities include volume, stress, load, security, scalability, performance etc. Hardware and software is not concerned with functional testing.

Test Item tree is a data analytical method which allows constructing a hierarchical structure on the items of a questionnaire or test from observed response patterns.

Assume that we have a questionnaire with m items(see below q1,q2,q3, etc..) and that subjects can answer positive (1) or negative (0) to each of these items, i.e. the items are dichotomous. If n subjects answer the items this results in a binary data matrix D with m columns and n rows. Typical examples of this data format are test items which can be solved n(1 )or failed n(2) by subjects. Other typical examples are questionnaires where the items are statements to which subjects can agree (1) or disagree (0).

We will send "End to Testing Checklist" and "Test Summary Report". These reports includes what features we cover into the application and defects and other details.

Smoke testing-it is a bulid verification test.
only the essential functionalities will be checked.

Sanity testing-only sanity of code will be checked.
Particular code will be checked before it actually combined to existing system.

To know about the status of the project use RTM

Schedule Variance = Actual Scheduled - Planned Schedule

FRD stands for functional Requirement Document. The first type of testing you would do when the FRD is ready and approved is STATIC TESTING. This involves studying the work documents like the Requirement document itself to see if there are any errors in it before you start your requirement extraction into an Excel Spreadsheet.

At this early stage OD the testing cycle where your Requirement Documents is just being approved, the application under test is most likely not ready, so you can not carry out Smoke Testing or Sanity Testing.

Equivalence partitioning is a technique that divides the i/p domain of a program into classes of data from which test cases can be delivered.
- For each piece of the specification, generate 1 or more eqvilence classes.
- Label the classes as "valid" and "invalid"
- Generate testcases that cover as many possible valid and invalid wquilance classes

Boundary value Analysis : a technique in which the testcases that explore the boundary conditions have a higher probability of detecting error.
- verify the faults at near boundaries
- Faults tend to arround near boundaries
- Good place to look for faults
- Test values on bothsides of boundaries

Formula:
Valid boundaries: minimum, maximum
Invalid boundaries: min-1, max+1

Functional Testing sometimes called black box testing because no knowledge of the internal logic of the system is used to develop testcases.for example ,if a certain function key should produce a specific result when pressed, a functional tet validates this expectation by pressing the function key and observing the result.when conducting functional tests, you will use validation techniques almost exclusively.
Functional testing advantages:
simulates actual system usage.
makes no system structure assumptions.

Disadvantages
Potential of missing logical errors in software
possibility of redundant testing.

Functionality Testing:
Its part of Functional testing. Giving the input and checking the output. Testing the application against specifications.

If you donot have much time to test the whole application, then the best approach is by giving priorities to the functions or the modules.

For example, login window of an application has a very high priority, caz it authenticates the user and allows the users to access the application.

Another example, if its a database apllication, you need to check the users rights in the login screen, data storing by checking data addition, deleting and edyting etc.