Explain Regression Testing Techniques?

Answer

Software maintenance is an activity which includes enhancements, error corrections, optimization and deletion of existing features. These modifications may cause the system to work incorrectly . Therefore , Regression Testing becomes necessary. Regression Testing can be carried out using following techniques:

Retest All

• This is one of the methods for regression testing in which all the tests in the existing test bucket or suite should be re-executed. This is very expensive as it requires huge time and resources.

• Instead of re-executing the entire test suite, it is better to select part of test suite to be run
• Test cases selected can be categorized as 1) Reusable Test Cases 2) Obsolete Test Cases.
• Re-usable Test cases can be used in succeeding regression cycles.
• Obsolete Test Cases can't be used in succeeding cycles.

• Prioritize the test cases depending on business impact, critical &  frequently used functionalities . Selection of test cases based on priority will greatly reduce the regression test suite.