Delivery Hero : Data Engineer - 2 Interview Experience | 7 YoE

Round 1: Get To Know

-Can you tell me about your past experiences and projects?

-What challenges did you face, and how did you tackle them?

-Why did you apply to Delivery Hero?

-How do you keep up with learning? Have you attended any conferences or engaged in other learning activities?

Round 2: Hiring Manager

-What does an ideal team look like to you?

-What kind of team would you prefer not to work with?

-How do you handle situations where you disagree with feedback from others?

-Can you describe a challenge you faced and how you resolved it?

-What is a mistake you made, and how did you overcome or resolve it?

-How do you compare the time investment and value of a task?

-Can you describe a project you successfully accomplished? What did you do to achieve that success?

-What metrics do you use to determine whether a spark job is going well or not?

-How would you handle a schema change when new files arrive?

Round 3: Technical - Coding and System Design

Write a python code that determines if all the people in their seats can see the screen in the theatre. A person can see the screen if their number is greater than the number before/in front of it.

Example where everyone can see:

FRONT STAGE

[[1, 2, 3, 2, 1, 1],

[2, 4, 4, 3, 2, 2],

[5, 5, 5, 5, 4, 4],

[6, 6, 7, 6, 5, 5]]

Example where they cannot see:

FRONT STAGE

[[1, 2, 3, 2, 1, 1],

[2, 4, 4, 3, 2, 2],

[5, 5, 5, 9, 4, 4],

[6, 6, 7, 6, 5, 5]]

-Write a SQL query to find the second highest salary in each department. If a department has less than two employees, return NULL for that department.

-System Design - How would you design a cost-effective, scalable, and efficient data pipeline for an e-commerce website that ingests, processes, and stores the data?

-Apache Spark related questions – Fundamentals, Data skewness, narrow vs wide transformations, optimised joins.

-Airflow related questions – Fundamentals, operators, XCom

-Kafka related questions – Fundamentals, consumer groups, offset management

Round 4: Technical - Bar Raiser

-Can you tell me about your past experiences and projects?

-How would you implement a program to determine the frequency of each letter in a given string, such as "asrfrfgg," producing an output like "a1s1r2f2g2," while considering the time and space complexity of your solution?