Data Engineer Interview Questions
Practice 160 real Data Engineer interview questions for 2026. Covers companies like Meta, TikTok, RBC Royal Bank, and Point72 — real questions from actual interviews with detailed solutions. This collection of Data Engineer interview questions is designed for hands‑on interview preparation: expect live SQL and Python exercises, pipeline design and debugging, and case problems that test data modeling, throughput and latency tradeoffs. What’s distinctive about data engineering interviews is the mix of coding plus systems thinking: interviewers evaluate SQL fluency and data modeling, end‑to‑end pipeline architecture (streaming, Spark, Kafka) and data reliability/observability. Meta, TikTok, RBC Royal Bank, and Point72 are actively hiring for this role and commonly test scalable ETL design, warehouse/schema design and production reliability. To prepare, practice medium‑to‑hard SQL, build a few Spark/streaming exercises, sketch architecture tradeoffs for high‑throughput pipelines, and rehearse concise behavioral stories that show ownership and incident response.
"I got asked a hardcore MCM DP question and I saw it on PracHub as well. Solved that question in 5 minutes. Without PracHub I doubt I could solve it in 5 hours. Though somehow didn't get hired, perhaps I guess I solved it too fast? /s"
"Believe me i'm a student here jn US. Recently interviewed for MSFT. They asked me exact question from PracHub. I saw it the night before and ignored it cause why waste time on random sites. I legit wanna go back and redo this whole thing if I had chance. Not saying will work for everyone but there is certainly some merit to that website. And i'm gonna use it in future prep from now on like lc tagged"
"10 years of experience but never worked at a top company. PracHub's senior-level questions helped me break into FAANG at 35. Age is just a number."
"I was skeptical about the 'real questions' claim, so I put it to the test. I searched for the exact question I got grilled on at my last Meta onsite... and it was right there. Word for word."
"Got a Google recruiter call on Monday, interview on Friday. Crammed PracHub for 4 days. Passed every round. This platform is a miracle worker."
"I've used LC, Glassdoor, and random Discords. Nothing comes close to the accuracy here. The questions are actually current — that's what got me. Felt like I had a cheat sheet during the interview."
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"Legit the only resource you need. TC went from 180k -> 350k. Just memorize the top 50 for your target company and you're golden."
"PracHub Premium for one month cost me the price of two coffees a week. It landed me a $280K+ starting offer."
"Literally just signed a $600k offer. I only had 2 weeks to prep, so I focused entirely on the company-tagged lists here. If you're targeting L5+, don't overthink it."
"Coaches and bootcamp prep courses cost around $200-300 but PracHub Premium is actually less than a Netflix subscription. And it landed me a $178K offer."
"I honestly don't know how you guys gather so many real interview questions. It's almost scary. I walked into my Amazon loop and recognized 3 out of 4 problems from your database."
"Discovered PracHub 10 days before my interview. By day 5, I stopped being nervous. By interview day, I was actually excited to show what I knew."
"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
"The search is what sold me. I typed in a really niche DP problem I got asked last year and it actually came up, full breakdown and everything. These guys are clearly updating it constantly."
Describe Resolving Stakeholder Trade-Offs
Tell me about a time when you worked with multiple stakeholders who had different needs or priorities, and you had to create a solution that satisfied...
Choose a Metric Hierarchy for a Humanoid-Robot Fleet
Create a metric hierarchy for a humanoid-robot fleet spanning useful task completion, autonomy, reliability, safety, charging, operations, and data he...
Build a Firmware Data Quality and Release-Feedback Framework
Design a firmware telemetry quality framework that brings data and firmware teams together around versioned contracts, pre-release tests, canary check...
Diagnose the Leading Cause of Slow or Failed Charging
Analyze a robot-charging reliability case by defining failure and exposure, ranking root causes, and investigating slow sessions with imperfect teleme...
Explain production model drop to a PM
Role Play: Communicate Model Degradation to a Non-Technical PM You are a data scientist. A PM says: > “Your model performed great on the validation se...
Answer conflict and ambiguity with STAR stories
Job Fit / Behavioral: STAR Stories Prepare answers using the STAR (Situation, Task, Action, Result) format for the following prompts: 1. Tell me about...
Solve two string problems
You are asked to solve the following two coding problems. 1. Count unique Morse code translations You are given an array of lowercase English w...
Compute transaction fees from a CSV string
You are given a CSV string representing a list of payment transactions. Write a function that parses the CSV and returns a CSV string with the total p...
Design a Pipeline to Process a Billion Clickstream Events Per Day
You are designing the data infrastructure for a large consumer web/mobile product. The product emits a clickstream: every page view, tap, scroll, and ...
Describe a project and its impact
You are interviewing for a Staff Data Engineer role supporting information security (e.g., detection engineering, alerting, network/security infrastru...
Implement Portfolio Trading Optimizer
You are given an array prices, where prices[i] is the price of one stock on day i. You may perform multiple buy/sell transactions over the period, but...
Solve SQL and PySpark Data Tasks
This question evaluates proficiency in SQL query design and PySpark DataFrame manipulation, covering aggregation, filtering, joins, time and numeric f...
Defend a Data Pipeline Architecture and Its Trade-offs
Prompt Choose one production data pipeline that you personally designed or substantially changed. Walk through its architecture, the requirements that...
Explain ETL schema changes and ensure integrity
Behavioral / Data Engineering Discussion Prompts You’re interviewing for a Data Engineer role. Answer the following prompts with concrete examples fro...
Answer DE behavioral and ramp-up questions
Answer the following behavioral questions for a Data Engineer (or data-focused full-stack) role. Provide specific examples. 1. Project under a tight d...
Describe past NLP work and collaboration
Scenario In an initial phone screen, the interviewer asks you to introduce yourself, then drills into your resume. Questions (answer using concrete ex...
Write queries for follows and bookings
This question evaluates the ability to manipulate temporal event logs, enforce bidirectional relational integrity, and implement efficient graph and i...
Write SQL to analyze CA residency history
You have two SQL tables. Table 1: user_info (current snapshot) - id (user id) - shard (partition column) - name - country - state - created_date Table...
Find Top Creators and Login Streaks
This question evaluates proficiency in data aggregation, algorithmic optimization for top-k retrieval, and SQL time-series analysis using window funct...
Encode and Rebuild a Binary Tree
Design two functions for a binary tree: - encode(root) -> string - decode(data) -> root Each tree node contains an integer value and has up to two chi...