Tuesday, January 17, 2012

What Is Regression Testing Explain It with Example?

When a bug is fixed by the development team than testing the other features of the applications which might be affected due to the bug fix is known as regression testing

Regression testing is always done to verify that modified code does not break the existing functionality of the application and works within the requirements of the system.

Regression Testing Example - Real and Practical 

Example of regression testing with its process is explained below:

For Example there are three Modules in the Project named Admin Module, Personal Information, and Employment Module and suppose bug occurs in the Admin Module like on Admin Module existing User is not able to login with valid login credentials so this is the bug. 

Now Testing team sends the above - mentioned Bug to the Development team to fix it and when development team fixes the Bug and hand over to Testing team than testing team checks that fixed bug does not affect the remaining functionality of the other modules (Admin, PI, Employment) and also the functionality of the same module (Admin) so this is known as the process of regression testing done by Software Testers.

What is Regression Testing with its Strategies?

Regression testing is achieved after the bug fixed, means testing the operation whether the fixed defect is affecting remaining functionality of the application or not. Usually in regression testing bug fixed module is tested. During regression testing tester always check the entire system whether the fixed bug make any adverse affect in the existing system or not.

There are mostly two strategies to regression testing, 1) to run all tests and 2) always run a subset of tests based on a test case prioritization technique.

When will we do Regression Testing?

Regression testing is the re-testing of features to make safe that features working earlier are still working fine as desired.

It is executed when any new build comes to QA, which has bug fixes in it or during releasing cycles (Alpha, Beta or GA) to originate always the endurance of product.


Regression testing will be conducted after any bug fixed or any functionality changed.


  1. Nice information by the author really informative thanks.

  2. Nicely explained by the author keep it up with more on software testing its really nice, this blog is good to see because all the information is unique and also good for interview point of view.

    To be very frank i never seen regression testing information before like that because author has explained it nicely especially regression testing example.

  3. very nice information....thanks for it !!!

  4. Very nice...Thank you for the clear information.

  5. thanks blogger for properly explaining regression testing with example....

  6. this is very useful and nice ................thaks

  7. Very Good,Helpful Explanation..........Thanks

  8. nice answers..thank you

  9. Nice answer but one confusion will come ,How will we know in regression testing that the problem occurring is exactly due to fixing the particulate bug.

    1. Consider that every module works fine except one which needs a fix, and when the bug is fixed and sent for testing and when the testing team finds a new bug then obviously we can say that a new problem has araised 'coz of a new fix...

    2. My comment would be, if the one bug fix is done ans a retest of the system is done with exisiting and/or sub tests, then the bug "should" be the only reason that an error/bug is found on a system test.

  10. Whats the difference between regression testing and sanity testing? Both are done after bug fix is done. Then why two different terminologies?

  11. cna you give examples pliz

  12. please create same blogs for sql, t-sql also.

  13. Excellent article ..... thanks

  14. any suggestion on the test cases for a website?