How to ace a QA interview
Embarking on a journey toward a career in software testing is an exciting and rewarding endeavor. As a software tester, the gateway to your dream job often involves navigating the challenging terrain of a Quality Assurance (QA) interview. Whether you’re a seasoned professional looking to make a career move or a budding enthusiast eager to step into the world of software testing, mastering the art of answering QA interview questions is essential.
In this comprehensive guide, we delve into the intricate landscape of QA interview questions, offering valuable insights, tips, and strategies to help you not only survive but thrive in your software testing interviews. From fundamental concepts to advanced methodologies, we’ll explore a diverse array of topics that encompass the core competencies sought by interviewers in the dynamic field of software testing.
Let’s begin!
What is black-box testing?
Black box testing involves testing a software system in which we know only the input but do not see how the output gets produced.
What is functional testing?
Functional testing is one type of black-box testing. It consists of testing functions by feeding them input and evaluating the output. However, there is rarely a consideration for the inner workings of a program.
What is regression testing?
There are two ways to use regression testing, and familiar to these is the idea of reusing old tests.
- To ensure that a fix does what it’s supposed to do.
- To ensure that a fix does not compromise the overall integrity of a program.
What is acceptance testing?
Acceptance testing, or otherwise User Acceptance Testing (UAT), is the testing performed by end-users or stakeholders of a piece of software. It mainly tends to focus on validation-type testing.
What is the difference between validation and verification?
The IEEE Standard Glossary of Software Engineering Terminology (Std 610.12-1990) defines validation as below.
“The process of evaluating a system or component during or at the end of the development process to determine whether it satisfies specified requirements.”
On the other hand, the same standard defines verification as follows.
- (1) The process of evaluating a system or component to determine whether the products of a given development phase satisfy the conditions imposed at the start of that phase.
- Formal proof of program correctness.
What is load testing?
Load testing is a performance testing technique that sees a system’s behavior under heavy demand. Load testing examples include but are not limited to the following.
- Test the system with the maximum number of users allowed.
- Send the maximum number of requests a system can handle at any time.
- Send the largest file size that a system can handle.
- Test a system under low memory conditions.
What is stress testing?
Stress testing is a performance testing technique used to test a system close to and beyond its “breaking point.” I’s intention is to test the robustness of a system. Below are some of the things that we can measure by conducting a stress test.
- How well the system performs under extreme load.
- How well the system’s error handling capabilities perform under stress.
- What is the maximum number of users that the system can handle before failing?
- How well the system performs when taking the maximum number of requests per second.
What are equivalence classes?
When we expect the same result from two tests, we say they are equivalent. A group of tests forms an equivalence class if they meet the following criteria.
- They all test the same thing.
- If one test catches a bug, the others probably will, too.
- If one test doesn’t catch a bug, the others probably won’t as well.
Source: Kaner, Falk, Nguyen. Testing Computer Software, pp. 128.
What is equivalence partitioning?
Equivalence partitioning is a systematic software testing technique where the input domain of a system is divided into groups or partitions of equivalent conditions. The objective is to simplify test case selection by identifying representative values from each partition, as inputs within the same partition are expected to produce similar behaviors from the software.
Moreover, focusing on testing only one representative from each equivalence class makes the testing process more efficient, covering a wide range of scenarios while avoiding unnecessary redundancy.
What are state transitions?
State transitions refer to the different states that an application can be in. Take, for instance, an e-commerce website. When a user clicks Checkout, they see a payment screen; once they enter their payment info and click Purchase, it results in an empty shopping cart, followed by a confirmation screen.
Here are some of the things that we could test in this scenario.
- Does the program switch correctly from state to state?
- Is it possible to make the application do these things out of sequence?
- Is it possible to make the application lose track of its current state?
- What does the program do with user input while switching between states?
- Does the user get charged more than once if we click Purchase multiple times?
- Does the program crash if we refresh the application while processing a transaction?
What is a race condition?
A race condition can occur between two events. For the sake of argument, let’s call these events X and Y. If X comes first, the program works. Since the program always expects X to go first, it fails whenever Y comes first.
Race conditions can be challenging to troubleshoot because they only occur under particular conditions. Therefore, be vigilant for race conditions whenever you have “irreproducible” bugs!
What are boundary conditions?
Let’s assume we have a program with an input field where users can enter the current month in number format (e.g., January = 1 and December = 12). That would mean that the numbers between 1 and 12 (inclusive) would be acceptable values, while anything outside this range would be unacceptable or outside the boundaries. One boundary case would be 0 and 1; another possibility would be 12 and 13.
Not every boundary in a program is intentional, and not all intended boundaries are set correctly. This is what most bugs are–most bugs cause a program to change its behavior when the programmer didn’t want or expect it to, or cause the program not to change its behavior when the programmer did expect it to. Not surprisingly, some of the best places to find errors are near boundaries the programmer did intend.
Kaner, Falk, Nguyen, Testing Computer Software, pp. 5
What is beta testing?
We use beta testing to get user feedback. The main idea is to let people who represent your market use your unfinished product as if it were the finished version. Their feedback is used to solve most remaining bugs and any necessary changes before delivering the product to the market.
What is performance testing?
Performance testing is a type of non-functional testing. We use it to evaluate the performance of an application in varying circumstances. Moreover, it helps shine the light on areas of an application that need improvement before launching to the market.
Performance testing includes but is not limited to the following.
- Load testing
- Stress testing
- Soak testing
What is white box testing?
White box testing involves testing a software system in which we know the input and output and how the output gets produced.
What is risk-based testing?
Risk-based testing is a strategic approach to software testing that prioritizes testing activities based on the perceived risks associated with different components or functionalities of the system. This method involves identifying, assessing, and prioritizing potential risks, considering factors such as the probability of occurrence and the potential impact on the project.
Test efforts are then directed towards areas with higher perceived risks, allowing for more efficient resource allocation and increased focus on critical aspects of the software. By aligning testing efforts with project risks, risk-based testing aims to uncover and address the most significant threats to the software’s quality, ensuring that testing activities contribute most effectively to the project’s overall success.
Related articles
- Selenium interview questions
- Java interview questions
- JMter interview questions
- Regression testing detailed guide
Follow our blog
Be the first to know when we publish new content.
How to interview a senior QA
- What is headless testing in Selenium? - October 10, 2023
- Distributing JMeter Tests - June 4, 2023
- JMeter: Testing JMS Messaging Systems - June 2, 2023