Interview questions
Preparing for a data engineering interview at Delivery Hero? This page contains 20 real interview questions sourced from verified Delivery Hero interview experiences. Questions are sorted by frequency — the ones asked most often appear first.
Delivery Hero data engineering interviews typically focus on Python/Coding, Spark/Big Data, and Behavioral. There's a solid mix of fundamental and advanced questions, making it accessible for candidates at multiple experience levels.
Use the difficulty filters above to focus your preparation. For each question, attempt your own answer first, then compare with our expert solution. You can also practice these questions in our AI Mock Interview Coach for real-time feedback.
What is the difference between narrow and wide transformations in Apache Spark? Explain with examples.
Explain the difference between Spark's map() and flatMap() transformations.
Explain the concept of Broadcast Join in Spark. When should it be used?
What is the difference between a list and a tuple in Python?
Explain the difference between shallow copy and deep copy in Python.
Write a Python function to find the first non-repeating character in a string.
What are decorators in Python, and how do they work?
Explain the difference between args and kwargs in Python.
What challenges did you face, and how did you tackle them?
What would you do if a pipeline failed and you couldn't find the reason?
Why do you want to join this company?
Briefly explain the architecture of Kafka.
When and how do you use Broadcast Join in Spark?
Write a Python function to find the first non-repeating character in a string.
Why did you apply to Delivery Hero?
How would you implement a program to determine the frequency of each letter in a string?
Implement a program to find the intersection of two lists.
Implement a program to remove duplicates from a list while maintaining order.
How do you compare the time investment and value of a task?
How would you design a cost-effective, scalable, and efficient data pipeline for an e-commerce website?
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