Lead Data Engineer Questions and Answers for Job Interview

As more and more devices and systems are designed that collect and interpret data, a greater number of engineers are required to process, store and transform this data so that businesses and consumers can get the most value from it. A lead data engineer is one role that helps to do this, taking a senior role in data management projects and helping companies find innovative ways to organise and use their data.

If you’re looking for a new opportunity in this industry or want to advance your career by applying for lead data engineer jobs, preparing for a job interview is one of the key ways that you can improve your chances of success. In this article, we explain what is required in a lead data engineer role and talk through common data engineer interview questions and answers to help you understand what the application process might involve.

What is a Lead Data Engineer?

A data engineer is a type of engineer responsible for preparing raw data for a range of different uses. This involves collecting, sorting and analysing data, as well as creating infrastructure that stores, manages and converts data either for their use or for data scientists and analysts to use.

Data engineering requires software development skills as well as specific knowledge of information systems and data management. A lead data engineer will be required to find solutions to managing large amounts of raw data for different purposes.

The role of lead data engineer usually involves taking the lead role on a project or in a team, often requiring senior experience in data engineering. Within this role, you’ll be required to do all of the usual responsibilities of a data engineer, along with leadership responsibilities.

What Does a Lead Data Engineer Do?

Lead data engineer jobs require a range of different skills, and the purpose of the data management and analysis will differ depending on the company and sector. The following list is an example of the different responsibilities that might make up a data engineer’s day-to-day role.

• Analysing and organising raw data
• Designing, building and maintaining digital architecture for data 
• Facilitating and overseeing data operations such as data extraction, transformation and storage
• Developing data pipelines
• Creating data modelling processes
• Compiling and organising data from multiple sources 
• Maintaining digital architecture
• Testing and refining frameworks and databases
• Running and reporting on data analysis
• Interpreting data, identifying trends and sharing insights
• Designing and delivering updates to ensure continued efficiency 

Lead Data Engineer Interview Questions

When you’re interviewing for lead data engineer jobs, you’re likely to be asked a range of technical questions and broader questions about your leadership and management skills and experience. Below are some of the most common lead data engineer interview questions to help you get an idea of what to prepare for.

Why did you choose a career in Data Engineering?

One of the classic questions for data engineer interviews asks the candidate about why they’ve chosen this particular sector. In your answer, you should talk about your background, what interested you in data engineering in the first place, and also any particular areas that you’re passionate about. It can also be useful to highlight whether there’s any work in this sector that you’d really like to do, or any aspirations that are motivated by something personal.

What data tools or frameworks do you have experience with?

This question is usually asked in interviews as a way to gauge your previous experience and identify whether you’ll be able to hit the ground running in your new role. You should talk about the tools that you have the most experience using for data engineering tasks and also whether you have any preferences. If you can talk about particular projects you’ve used the tools for, that can help to improve your answer.

How much experience do you have with data modelling?

Data modelling is a key part of many data engineering roles, and as a lead engineer in particular, most employers will be looking for candidates with experience in this area. One of the best ways to answer this question is to give specific examples of past projects where you have used data modelling, to illustrate your point.

Can you tell us a bit more about the data engineer certifications you have earned?

Since a lead data engineer is quite a senior role, candidates who have particular certifications in this area will likely do better in interviews if they can highlight that they have these qualifications and what the benefits of this are. If you have data engineer certifications, talk about why you chose them specifically and what they have led you to be able to do, to highlight their and your value.

Which non-technical skills have you found most valuable in your role as a data engineer?

Alongside data engineer technical interview questions, when you’re interviewing for a lead role you will also be assessed on your non-technical, soft skills. This question is asking you to highlight these skills, but also to share why you think they benefit you in a data engineering role in particular.

It’s a good idea to list 2-4 skills and provide an example of when this skill has benefited you in your role. Having experiences to draw on helps to enforce your points and provides a much more persuasive answer than just listing skills without any evidence.

What do you think is the hardest aspect of being a data engineer?

In a data engineer interview, there are often broad questions like this one that explore your experience of the data engineer role. When you’re interviewing for a lead position, the interviewer will want to know that you have a full understanding of what the role requires, which is what questions like this are used to determine.

In your answer, you can talk about a general challenge or something that you personally have struggled with. For the latter, remember to also focus on how you’ve overcome or are overcoming this challenge to demonstrate self-awareness and resilience.

Can you explain the difference between structured data and unstructured data?

Alongside data engineer scenario-based interview questions, you’ll likely also be asked technical questions like this one to check your practical and theoretical understanding of data engineering. The answer to this one is that structured data is stored in a particular format and often very specific, whilst unstructured data may include a range of different types of data that are stored in different formats.

Can you list and explain the design schemas involved in data modelling?

There are six main types of design schemas that can be used in data modelling: the flat model, hierarchical model, network model, relational model, star schema, and snowflake schema. In the answer to this data engineer interview question, you should list each of these and give an example of the type of data modelling project that you would use each of them for.

What are the pros and cons of working in a cloud computing environment?

Plenty of data engineers store their data in the cloud, and if you’re applying to work at a company that does this, you’ll likely be asked a question about this kind of environment. If you can give an example of previous experience as part of your answer, that’s great, but just knowing the pros and cons is still important.

Some of the advantages of working in a cloud computing environment are that you’re not required to secure physical hardware, scaling applications is quick, you can deploy applications globally, and you’re not limited to where you own data centre space, which improves the consumer experience. Disadvantages include the potential for vendor mismatches, complex costing systems, control issues and a reliance on fast and secure internet connection.

How can data analytics help the business grow and boost revenue?

This interview question for a data engineer is based on your knowledge of the value of data analytics, which is something that a lead data engineer will be expected to know and potentially required to talk about. You should share your opinion on how it can help with business and revenue growth and share some specific examples of the areas where it can make an impact. If you’ve helped to do this in a previous role, this is also a good time to share that.

When did you face a challenge in dealing with unstructured data and how did you solve it?

A key way in which an interviewer will gauge your suitability for a role is by asking about previous situations that you’ve dealt with at work. In data engineer scenario-based interview questions like this one, you are being asked to talk about a challenge and share how you approached finding a solution.

As with any interview question based on a past struggle, you should focus your answer on how you overcame the challenge and what you learned from it. This demonstrates that you’re practical and good at problem-solving, along with the fact that you’re not someone who repeats mistakes.

Have you ever played an active role in solving a business problem through the innovative use of existing data?

Lead data engineers are expected to be innovative and proactive, leading projects and helping businesses solve problems using data. This question is looking for examples in your career where you’ve demonstrated this ability and should be answered by talking through how you noticed the problem, what you proposed, how you deployed your solution and the impact that this made.

Summary

The role of a lead data engineer is an exciting position, offering chances to work with large amounts of data, take the lead in projects and manage other engineers and analysts. It’s a great opportunity for engineers who enjoy practical work with data but also who have good people skills and are ready to take the lead on projects and briefs.

If you want to succeed as a lead data engineer however, you need to be able to highlight your abilities and strengths in an interview process, which will be done through testing your technical skills and by how you answer interview questions. By researching the most common types of questions that candidates are asked for this role, and preparing answers that cover key points and help you appear more confident, you’ll give yourself the best possible chance of success when applying for new roles.

If you’re a data engineer looking for a job in the electronic embedded systems sector, KO2 is a specialist recruitment agency that can help you find your ideal role. Take a look at our current lead data engineer jobs or get in touch to speak to our team about how we can help.