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."
"The solution quality is insane. It covers approach, edge cases, time complexity, follow-ups. Nothing else comes close."
"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."
Implement phrase search and JSON path
This question evaluates the ability to build an inverted index for in-memory exact phrase search and to implement JSON path traversal with wildcard ma...
Compute capacities after site closures
You are given a nested dictionary redistribution where redistribution[closed_site][dest_site] equals the additional capacity required at dest_site if ...
Find customer with max rentals in consecutive weeks
You are given a table purchases(customer_id INT, purchase_date DATE, rented_copies INT). Consider only dates in calendar year 2024. Define a full week...
Compute missing letters to form original string
Implement a function that, given two strings original and typed (typed is a misspelled/partial version of original), returns the number of additional ...
Write PostgreSQL string-manipulation query
You are given a PostgreSQL table clickstream(session_id TEXT, page TEXT, query TEXT, ts TIMESTAMP). The page column contains full URLs like 'https://s...
Walk through resume and project highlights
Resume Walkthrough — Data Engineer Technical Screen Context You are interviewing for a Data Engineer role. The interviewer wants a concise, impact-foc...
Solve three SQL problems (easy/medium/hard)
Answer the following SQL tasks of increasing difficulty: 1) Aggregation: Given Orders(order_id, customer_id, amount, order_date), return each customer...
Validate carpool capacity
Question LeetCode 1094. Car Pooling – Given trips[i] = [numPassengers, start, end] and an integer capacity, return true if the vehicle can fulfill all...
Aggregate Netflix metrics in SQL
Question Netflix video-streaming analytics SQL: Write a simple aggregation (e.g., total watch-time per day). Build a cumulative metric: today’s metric...
Demonstrate behavioral competencies
Demonstrate behavioral competencies Behavioral Interview Prompt: Prepare STAR Stories Context You are preparing for an onsite Behavioral & Leadership ...
Write SQL for active follow connections
Table: follow_events(requester_id INT, target_id INT, event STRING CHECK (event IN ('request_follow','follow_success','follow_reject','unfollow')), ev...
Describe a data-heavy project
Describe a data-heavy project Behavioral/Technical: Data‑Heavy Project Deep Dive (Data Engineer) Describe one data‑heavy project from your resume. In ...
Compute unique duration by merging intervals
Problem You have an autonomous-driving clip dataset where each row represents a time interval from a driving run. Table: clips | column | type | descr...
User Activity Analytics: Unique Users per Activity and Average Time on Site
User Activity Analytics You are given a collection of records, where each record captures a single user's action on a website. Each record is a dictio...
Compute shipping cost with tiered pricing
You are building a shipping-cost calculator. Each order contains line items, and shipping rules vary by destination country and product. Assume: - Ord...
Connect Points With Minimum Total Distance
This question evaluates a candidate's competency in graph modeling, geometric distance metrics, and algorithmic complexity analysis for optimizing tot...
Compute Graph Spread and Portfolio Trades
This question evaluates graph traversal and data-manipulation competencies, combining connected-component analysis on undirected graphs with map-based...
Merge Overlapping Time Intervals
You are given a list of closed time intervals. Each interval is represented as [start, end], where start <= end. Write a function that returns the sma...
Implement a DAG task graph
This question evaluates competency with directed acyclic graphs, graph algorithms (topological sorting), dependency modeling, and implementing data st...
Generate All Valid Combinations of Balanced Parentheses
Generate All Valid Combinations of Balanced Parentheses Given an integer n representing the number of pairs of parentheses, generate all distinct stri...