The Data Engineering Interview Loop

Data engineering interviews tend to follow a standard format, but the focus and order can vary by company and role level. For instance, senior roles place more emphasis on behavioral questions, especially around leadership and team-building skills. Here’s a breakdown of the typical interview stages:

1. Recruiter Screen: Initial call to discuss your background and the role.
2. SQL Coding: Tests SQL skills, often with questions on writing efficient queries.
3. Data Structures & Algorithms Coding: Assesses problem-solving and coding abilities.
4. Data Modeling: Evaluates your approach to designing data models for various use cases.
5. ETL Pipeline Design: Focuses on designing scalable, efficient data pipelines.
6. Behavioral: Examines soft skills, such as teamwork, leadership, and resilience.
7. Concepts (optional): Some companies may include questions on specific data engineering concepts or technologies relevant to the role. This is typically not a separate interview round but is often incorporated into the Data Modeling or ETL Pipeline Design rounds. It’s more likely to appear in entry-level interviews, where candidates might have a shorter or combined version of these rounds.

Recruiter screen

Time estimate: 30 minutes

The recruiter screen is a quick discussion to summarize the job expectations for the role and and assess whether you’re a good fit.

Usually, the recruiter will provide details about the entire interview process and give materials to help you prepare. There may also be an initial discussion on compensation to make sure you are in similar ballparks.

SQL coding

Time estimate: 30 minutes

This part may take place as an online assessment (e.g., on platforms like HackerRank) or during a face-to-face technical interview. You’ll likely be asked to write efficient SQL queries ranging from simple aggregations to complex window functions.

Data structures & algorithms coding

Time estimate: 30 minutes

This portion might also be tested online (often alongside the SQL component) or in a live technical interview. Data structures and algorithms questions in data engineering interviews are usually less complex than those in software engineering interviews but still assess your ability to solve coding problems efficiently.

Data modeling

Time estimate: 45 minutes - 1 hour

A Data Modeling interview is an interactive, scenario-based discussion. You’ll be given a business scenario and asked to design a data model, typically including a dimensional model or ER diagram with 3-5 tables. The interview focuses on identifying business requirements, considering technical constraints, and adapting the model to feedback. You’re encouraged to ask clarifying questions, think aloud, and make iterative improvements. In some cases, you may also be asked to write SQL queries based on your data model to answer business questions.

ETL pipeline design

Time estimate: 45 minutes - 1 hour

The ETL Pipeline Design interview is another interactive, scenario-based session. You’ll design an ETL pipeline based on a business scenario, focusing on data sources and destinations, extraction, transformation, and loading processes. You’ll also address performance, scalability, and fault tolerance, adapting the design as needed based on feedback. Though no coding is required, you should be ready to discuss specific ETL tools, technologies, and techniques. Expect to ask clarifying questions and think aloud as you refine your solution with input from the interviewer.

Behavioral

Time estimate: 30 minutes - 1 hour

A hiring manager or potential teammate will assess your communication style and teamwork skills. They’ll look at your experience and past projects, how well you collaborate with other teams, and how you communicate across the company. For more senior roles, they’ll also evaluate your abilities in project management, leadership, and handling conflicts.

Company-specific focuses

Understanding company-specific use cases provides valuable insights into what topics are prioritized during data engineering interviews. This section outlines typical use cases for several leading companies and highlights relevant skills.