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Data Engineer Interview Questions

Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.

9403
Questions
546
Companies
11
Topics
8
Languages

Showing 1–24 of 24 results

  • AirbnbMediumData Engineer
    Calculate the Median House Price in Each City

    Tests your ability to compute grouped medians in PostgreSQL, properly handling even and odd row counts, duplicate price values, and numeric precision.

    Data Manipulation (SQL/Python)Onsitesqlpostgresqlaggregations
  • AirbnbMediumData Engineer
    Estimate Page-Visit Duration from the Next User Event

    Implement logic to compute user page-visit durations based on adjacent event timestamps, deterministically resolving ties and handling boundary conditions for terminal events.

    Data Manipulation (SQL/Python)Onsitepythonsqldata-manipulation
  • AirbnbMediumData Engineer
    Find Hosts Meeting Listing, Rating, and Review-Coverage Rules

    Tests the ability to write a SQL query performing multi-table aggregations, date-windowed conditional logic, and host-level qualification filtering across listing counts, average ratings, and recent review coverage.

    Data Manipulation (SQL/Python)Onsitesqlaggregationconditional-logic
  • AirbnbMediumData Engineer
    Find Users with Seven Consecutive Impression Days

    Tests your ability to identify consecutive calendar-day activity streaks in PostgreSQL using window functions, date arithmetic, and deduplication.

    Data Manipulation (SQL/Python)Onsitesqlpostgresqlwindow-functions
  • ByteDanceMediumData Engineer
    Connect Points With Minimum Total Distance

    This problem tests your ability to model a geometric optimization task as a Minimum Spanning Tree (MST) problem and implement it efficiently using Kruskal's or Prim's algorithm.

    Coding & AlgorithmsOnsiteGraphsMSTGeometry
  • DiscordHardData Engineer
    Design Video Call Analytics Tables

    This question evaluates data modeling and analytics competencies including event schema design, dimensional modeling (facts and dimensions), ETL/cleaning and deduplication, and time-windowed SQL aggregation.

    System DesignOnsite
  • DisneyEasyData Engineer
    Behavioral Panel: Conflict, Critical Feedback, Competing Priorities and Culture Fit

    Behavioral and culture-fit questions for a senior data engineer: a conflict, critical feedback, competing priorities, the motivation for moving into data engineering, and personal questions about turning points, best and worst managers, and disliked subjects. It tests self-awareness, ownership and clear storytelling.

    Behavioral & LeadershipOnsite
  • DisneyEasyData Engineer
    Data Pipeline Design for Cloud and Hybrid On-Prem Environments on AWS and Azure

    A senior data engineering design question: build a data pipeline from operational sources to analytics on one cloud, then rework it for a hybrid on-premises and cloud environment and for both AWS and Azure. It tests tool selection and trade-offs, ingestion and storage design, data quality, security and portability.

    System DesignOnsite
  • DisneyEasyData Engineer
    Prompting an LLM to Migrate a Java Codebase to Python and Clean a Large Database

    Explain how you would prompt a large language model to migrate a Java codebase to Python and to help clean a database with tens of thousands of rows. It tests prompt design, verification of generated code and data fixes, data quality measurement, security of AI-assisted work and the handling of sensitive data.

    Software Engineering FundamentalsOnsite
  • MetaHardData Engineer
    Define and validate product metrics

    Define and validate product metrics evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Analytics & ExperimentationOnsite
  • MetaHardData Engineer
    Design batch and streaming ETL architecture

    Design batch and streaming ETL architecture evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    System DesignOnsite
  • MetaHardData Engineer
    Evaluate impact of short videos in feed

    This question evaluates competency in metrics definition, causal experimentation, product analytics, and feed system behavior within the System Design and Data Engineering domain.

    System DesignOnsite
  • MetaMediumData Engineer
    Recommend two-hop follows in Python

    This question evaluates fluency with graph traversal, set operations, deduplication, and frequency-based ranking in Python, targeting manipulation of directed "follows" relationships represented as dictionaries and is categorized under Data Manipulation (SQL/Python).

    Data Manipulation (SQL/Python)Onsite
  • MetaMediumData Engineer
    Return top-3 content per category

    This question evaluates the ability to perform grouped top-k selection, deterministic tie-breaking and ordering, and to reason about algorithmic efficiency when manipulating structured datasets in the Data Manipulation (SQL/Python) domain for a Data Engineer role.

    Data Manipulation (SQL/Python)Onsite
  • MetaMediumData Engineer
    Validate carpool capacity

    This question evaluates understanding of interval-based resource accounting and algorithmic reasoning with cumulative constraints, assessing skills in processing time-bound events and managing capacity limits.

    Coding & AlgorithmsOnsite
  • MetaMediumData Engineer
    Visualize Netflix metric trends

    This interview question evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer for Visualize Netflix metric trends states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Analytics & ExperimentationOnsite
  • MetaHardData Engineer
    Write SQL for car rental utilization by city

    This question evaluates proficiency in SQL querying and relational data modeling, focusing on time-interval overlap logic, distinct aggregation across joined tables, null handling, and safe computation of utilization metrics.

    Coding & AlgorithmsOnsite
  • NetflixHardData Engineer
    Design config rollout and click aggregation

    This problem tests your ability to design a global configuration distribution system combined with a high-throughput event processing pipeline to monitor rollout health.

    System DesignOnsiteDistributed SystemsReal-time AnalyticsEvent Streaming
  • NetflixHardData Engineer
    Explain concurrency and reliability tradeoffs

    This problem tests your understanding of balancing thread-safe resource management in a high-concurrency local environment against the systemic requirements of a distributed data pipeline.

    Software Engineering FundamentalsOnsiteConcurrencyDistributed SystemsCaching
  • NetflixHardData Engineer
    Implement phrase search and JSON path

    This problem tests your ability to process unstructured text into a searchable index and navigate hierarchical data structures using path patterns.

    Coding & AlgorithmsOnsiteInverted IndexString ProcessingRecursion
  • NotionMediumData Engineer
    Explain impact and partnership

    This question evaluates a Data Engineer's behavioral and leadership competencies, including ownership, cross-functional collaboration with data scientists and partners, stakeholder communication, problem framing, impact measurement, and responsiveness to managerial feedback, and is categorized under Behavioral & Leadership.

    Behavioral & LeadershipOnsite
  • ZooxMediumData Engineer
    Design teleoperations data models and pipelines

    This question evaluates competency in data modeling, real-time and batch pipeline architecture, telemetry ingestion, metrics design, and operational monitoring for teleoperations and autonomous vehicle stability.

    System DesignOnsite
  • ZooxMediumData Engineer
    Explain seasons and compound interest

    This question evaluates quantitative reasoning and basic scientific literacy by testing understanding of Earth's axial tilt and seasonal temperature variation alongside exponential growth and compound interest calculations.

    Software Engineering FundamentalsOnsite
  • ZooxMediumData Engineer
    Write SQL revenue and anomaly queries

    This question evaluates SQL proficiency and data engineering competency in revenue aggregation, netting purchases and refunds, joining transaction and vendor tables, and designing data quality and anomaly detection checks.

    Coding & AlgorithmsOnsite