Software Testing Basics - Software Testing Interview Questions and Answers
What is configuration management?
Configuration management is the detailed recording and updating of information for hardware and software components. When we say components we not only mean source code. It can be tracking of changes for software documents such as requirement, design, test cases, etc.
When changes are done in adhoc and in an uncontrolled manner chaotic situations can arise and more defects injected. So whenever changes are done it should be done in a controlled fashion and with proper versioning. At any moment of time we should be able to revert back to the old version. The main intention of configuration management is to track our changes if we have issues with the current system. Configuration management is done using baselines.
How does a coverage tool work?
While doing testing on the actual product, the code coverage testing tool is run simultaneously. While the testing is going on, the code coverage tool monitors the executed statements of the source code. When the final testing is completed we get a complete report of the pending statements and also get the coverage percentage.
Which is the best testing model?
In real projects, tailored models are proven to be the best, because they share features from The Waterfall, Iterative, Evolutionary models, etc., and can fit into real life time projects. Tailored models are most productive and beneficial for many organizations. If it's a pure testing project, then the V model is the best.
What is the difference between a defect and a failure?
When a defect reaches the end customer it is called a failure and if the defect is detected internally and resolved it's called a defect.
Should testing be done only after the build and execution phases are complete?
In traditional testing methodology testing is always done after the build and execution phases.
But that's a wrong way of thinking because the earlier we catch a defect, the more cost effective it is. For instance, fixing a defect in maintenance is ten times more costly than fixing it during execution.
In the requirement phase we can verify if the requirements are met according to the customer needs. During design we can check whether the design document covers all the requirements. In this stage we can also generate rough functional data. We can also review the design document from the architecture and the correctness perspectives. In the build and execution phase we can execute unit test cases and generate structural and functional data. And finally comes the testing phase done in the traditional way. i.e., run the system test cases and see if the system works according to the requirements. During installation we need to see if the system is compatible with the software. Finally, during the maintenance phase when any fixes are made we can retest the fixes and follow the regression testing.
Therefore, Testing should occur in conjunction with each phase of the software development.
Are there more defects in the design phase or in the coding phase?
The design phase is more error prone than the execution phase. One of the most frequent defects which occur during design is that the product does not cover the complete requirements of the customer. Second is wrong or bad architecture and technical decisions make the next phase, execution, more prone to defects. Because the design phase drives the execution phase it's the most critical phase to test. The testing of the design phase can be done by good review. On average, 60% of defects occur during design and 40% during the execution phase.