Data Engineer Interview Questions and Answers

Whether you’re new to the world of big data and looking to break into a Data Engineering role, or you’re an experienced Data Engineer looking for a new opportunity, preparing for an upcoming interview can be overwhelming. Given how competitive this market is right now, you better be prepared for your interview. The following are some of the top data engineer interview questions you can likely expect at your interview, along with possible reasons why these questions are asked, plus the answers that interviewers are typically looking for.

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Q: What is Data Engineering?

This may seem like a pretty basic question, but regardless of your skill level, this may come up during your interview. Your interviewer wants to see what your specific definition of data engineering is, which also makes it clear that you know what the work entails.  So, what is it? In a nutshell, it is the act of transforming, cleansing, profiling, and aggregating large data sets. You can also take it a step further and discuss the daily duties of a data engineer, such as ad-hoc data query building and extracting, owning an organization’s data stewardship, and so on. 

Q: How Does a Data Warehouse Differ from an Operational Database?

This question may be more geared toward those on the intermediate level, but in some positions, it may also be considered an entry-level question. You’ll want to answer by stating that databases using Delete SQL statements, Insert, and Update is standard operational databases that focus on speed and efficiency. As a result, analyzing data can be a little more complicated. With a data warehouse, on the other hand, aggregations, calculations, and select statements are the primary focus. These make data warehouses an ideal choice for data analysis.

Q: What Do *args and **kwargs Mean?

If you’re interviewing for a more advanced role, you should be prepared to answer complex coding questions. This specific coding question is commonly asked in data engineering interviews, and you’ll want to answer by telling your interviewer that *args defines an ordered function and that **kwargs represent unordered arguments used in a function. To impress your interviewer, you may want to write down this code in a visual example to demonstrate your expertise.

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Q: As a Data Engineer, How Have You Handled a Job-Related Crisis?

Data engineers have a lot of responsibilities, and it’s a genuine possibility that you’ll face challenges while on the job, or even emergencies. Just be honest and let them know what you did to solve the problem. If you have yet to encounter an urgent issue while on the job or this is your first data engineering role, tell your interviewer what you would do in a hypothetical situation. For example, you can say that if data were to get lost or corrupted, you would work with IT to make sure data backups were ready to be loaded, and that other team members have access to what they need.

Q: Do You Have Any Experience with Data Modeling?

Unless you are interviewing for an entry-level role, you will likely be asked this question at some point during your interview. Start with a simple yes or no. Even if you don’t have experience with data modeling, you’ll want to be at least able to define it: the act of transforming and processing fetched data and then sending it to the right individual(s). If you are experienced, you can go into detail about what you’ve done specifically. Perhaps you used tools like Talend, Pentaho, or Informatica. If so, say it. If not, simply being aware of the relevant industry tools and what they do would be helpful.

Learn the Skills Needed to Succeed as a Data Engineer

One of the best ways to crush your next job interview is to get formal training and earn your certification. If you’re an aspiring data engineer, enroll in our Big Data Engineer Course today and get started by learning the skills that can help you land your dream job.

Our Big Data Engineer Master’s Program was co-developed with IBM and includes hands-on industry training in Hadoop, PySpark, database management, Apache Spark, and countless other data engineering techniques, skills, and tools. Upon completion, you will receive certifications from both IBM and Simplilearn, showcasing your knowledge in the field of data engineering.

With the job market being so competitive nowadays, earning the relevant credentials has never been more critical. The technology industry is booming, and while more opportunities seem to open up as technology continues to advance, it also means more competition. A Data Engineering certificate can not only help you to land that job interview, but it can help prepare you for any questions that you may be asked during your interview. From fundamentals to advanced techniques, learn the ins and outs of this exciting industry, and get started on your career. 

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Simplilearn is one of the world’s leading providers of online training for Digital Marketing, Cloud Computing, Project Management, Data Science, IT, Software Development, and many other emerging technologies.

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