What is the difference between smoke and sanity testing?
Theme: Software Testing Techniques Role: Qa Engineer/Test Engineer Function: Technology
Interview Question for QA Engineer/Test Engineer: See sample answers, motivations & red flags for this common interview question. About QA Engineer/Test Engineer: Ensure software quality through testing and quality assurance. This role falls within the Technology function of a firm. See other interview questions & further information for this role here
Sample Answer
Example response for question delving into Software Testing Techniques with the key points that need to be covered in an effective response. Customize this to your own experience with concrete examples and evidence
- Definition: Smoke testing is a type of testing that focuses on quickly determining if the critical functionalities of an application are working as expected after a build or release. Sanity testing, on the other hand, is a subset of regression testing that verifies if the specific changes or fixes made to an application are functioning correctly
- Purpose: Smoke testing is performed to ensure that the major functionalities of the application are working before conducting further testing. It helps identify critical issues early in the testing process. Sanity testing is conducted to validate the specific changes or fixes made to an application, ensuring that they haven't introduced any new issues
- Scope: Smoke testing covers a broad range of functionalities to ensure the basic stability of the application. It is a high-level test that checks if the application is ready for further testing. Sanity testing, on the other hand, focuses on a specific area or functionality of the application that has been modified or fixed
- Depth: Smoke testing is a shallow and non-exhaustive test that aims to identify showstopper issues quickly. It does not involve detailed testing of individual components or features. Sanity testing, however, may involve more in-depth testing of the specific changes or fixes to ensure their correctness
- Execution Time: Smoke testing is usually performed after a build or release to quickly determine if the application is stable enough for further testing. It is a relatively quick test that can be executed within a short timeframe. Sanity testing is typically conducted after smoke testing or regression testing, focusing on the specific changes or fixes. It may take longer than smoke testing, depending on the complexity of the modifications
- Test Coverage: Smoke testing aims to cover the critical functionalities of the application, ensuring that they are working as expected. It does not cover all possible test scenarios or edge cases. Sanity testing, on the other hand, focuses on the specific changes or fixes and may involve more targeted test scenarios to validate their correctness
- Outcome: The outcome of smoke testing is to determine if the application is stable enough for further testing. If critical issues are identified during smoke testing, further testing may be postponed until the issues are resolved. The outcome of sanity testing is to validate the specific changes or fixes and ensure that they have not introduced any new issues
- Frequency: Smoke testing is typically performed on every build or release to quickly identify major issues. It is a repetitive test that helps ensure the stability of the application throughout the development process. Sanity testing, on the other hand, is performed when specific changes or fixes are made to the application, ensuring their correctness before proceeding with further testing
- Automation: Smoke testing can be automated to quickly validate the critical functionalities of the application. It helps save time and effort in repetitive testing. Sanity testing, depending on the complexity of the changes, can also be automated to ensure consistent and reliable validation of the modifications
Underlying Motivations
What the Interviewer is trying to find out about you and your experiences through this question
- Knowledge of testing concepts: Understanding the difference between smoke and sanity testing
- Experience in test planning: Ability to determine when to use smoke or sanity testing based on project requirements
- Attention to detail: Ability to identify and prioritize critical test scenarios for smoke and sanity testing
- Problem-solving skills: Capability to troubleshoot and resolve issues encountered during smoke and sanity testing
Potential Minefields
How to avoid some common minefields when answering this question in order to not raise any red flags
- Confusing smoke testing with sanity testing: Mixing up the definitions and purposes of smoke and sanity testing
- Lack of understanding of testing concepts: Not being able to explain the purpose and benefits of smoke and sanity testing
- Inability to provide examples: Failing to give clear examples of when smoke and sanity testing should be used