Regression Testing

Regression Testing:It retests previously tested segments to ensure that they still function properly after a change has been made to another part of the application.

Objectives:

• It determines whether systems documentation remains current
• It determines that system test data and test conditions remain current.

When do use regression testing:
When there is a high risk that new changes may affect unchanged areas of the application system.

Performance testing:
In this testing that the system will perform as specified at predetermined levels,wait times,static processes,dynamic processes and transaction processes.It is also tested at the client/browser and server levels.

Example:

• In database systems the response time relates to the time to obtain a report after clicking on a specific button.It may be difficult to specify the response times for each and every form/Report,but the time that can be generally specified,for example 30 seconds is reasonable.
• In real time or embedded systems the performance parameters are very significant.If the system demands,if the temperature exceeds 40 degrees then the valve will be opened with in 10milliseconds.Here this performance requirement is not met it may result in a catastrophe.

Hence performance testing is compulsory in process control and telecommunication software systems.

Sanity Testing:

Sanity testing is a cursory testing; it is performed whenever a cursory testing is sufficient to prove the application is functioning according to specifications. This level of testing is a subset of regression testing. It normally includes a set of core tests of basic GUI functionality to demonstrate connectivity to the database, application servers, printers, etc.

Smoke Testing:

Smoke testing is non-exhaustive software testing, ascertaining that the most crucial functions of a program work, but not bothering with finer details.