What are the Regression Testing techniques?

  Regression Testing Techniques

• Retest All - All the existing test cases should be re-executed. It is expensive because it requires  re-run all the test cases, huge time, resources. But It ensures there is no errors generated from modified code.                                                                                         
• Regression Test Selection - Select part of the test suite to be run and those selected test cases are categorized as,

                                                                               1. Reusable Test Cases.
                                                                               2. Obsolete Test Cases . 

          Cost of the selecting test cases is less than retest all techniques.

• Prioritization of Test Cases -  Schedule test cases so that test cases in higher priority are executed before executing test cases in lower priority. These test cases prioritization depends on business impact,critical and frequently used functionalities.