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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 31–60 of 129 results

  • Capital OneMediumData Engineer
    Explain production model drop to a PM

    This question evaluates a candidate's ability to explain production model degradation, translate technical diagnostics into non-technical language, and articulate trade-offs between user impact and delivery timelines.

    Behavioral & LeadershipTechnical Screen
  • ClickhouseMediumData Engineer
    Answer SQL And Data Warehouse Fundamentals For A Data Engineering Interview

    This problem tests foundational knowledge of SQL set operations, performance optimization techniques for join operations, and the architectural principles behind building scalable data warehouses.

    Data Manipulation (SQL/Python)Technical ScreenSQLData WarehousingWindow Functions
  • DRWEasyData Engineer
    Compute a Year-End Balance with Monthly Card Fees

    This problem tests logic implementation and data structure traversal, requiring the integration of conditional logic (fee waivers) into a sequential processing pipeline.

    Coding & AlgorithmsOnline AssessmentData ProcessingLogicAggregation
  • DRWEasyData Engineer
    Delete the Fewest Characters to Avoid Triple Repeats

    This problem tests string manipulation, greedy algorithm logic, and the ability to track character frequency counts to identify and prune violations of a constraint.

    Coding & AlgorithmsOnline AssessmentStringsGreedyArrays
  • DRWEasyData Engineer
    Implement Nested Transactions in an In-Memory Database

    This problem tests your ability to manage state and scope using stacks and dictionaries to implement transaction isolation in a key-value store.

    Coding & AlgorithmsOnline AssessmentHash MapStackTransactions
  • DRWEasyData Engineer
    Validate a Password Against Explicit Security Rules

    This problem tests string manipulation, character set validation, and the ability to apply a sequence of conditional checks efficiently.

    Coding & AlgorithmsOnline AssessmentStringsValidationIteration
  • DatabricksMediumData Engineer
    Diagnose data quality and pipeline performance issues

    Diagnose data quality and pipeline performance issues evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Behavioral & LeadershipTechnical Screen
  • 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
  • DisneyMediumData Engineer
    Design a clickstream ingestion and aggregation pipeline for billions of events per day

    Design an end-to-end clickstream pipeline that ingests roughly one billion telemetry events per day from web, mobile, and TV clients and serves both near-real-time dashboards and accurate finalized daily aggregates without lagging. The question covers staged architecture and back-of-envelope sizing, a durable partitioned log for back-pressure, event-time windowing with watermarks and allowed lateness, late-arriving data and the provisional-to-finalized lifecycle, exactly-once deduplication in Flink versus Spark Structured Streaming, autoscaling on consumer lag, hot-partition key skew, high-cardinality DAU/MAU with HyperLogLog, and reprocessing after a logic bug. A common Disney data engineer online assessment system design question.

    System DesignOnline Assessment
  • DisneyMediumData Engineer
    Generate All Valid Combinations of Balanced Parentheses

    This question tests a candidate's ability to apply recursive backtracking and combinatorial generation in a coding interview context. It evaluates understanding of constraint-based enumeration and string construction, core algorithmic skills frequently assessed in software engineering and data engineering roles.

    Coding & AlgorithmsOnline Assessment
  • DisneyMediumData Engineer
    Generate All Well-Formed Parenthesis Strings

    This question tests practical understanding of recursion and backtracking through enumeration of all valid parenthesis combinations of a given length. It is a classic coding interview problem that evaluates combinatorial reasoning, constraint-based pruning, and familiarity with Catalan number sequences in algorithm design.

    Coding & AlgorithmsOnline Assessment
  • 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
  • FigmaMediumData Engineer
    Write SQL for first share and closest collaborator

    This question evaluates SQL proficiency—specifically joins, filtering, type casting, temporal aggregation, window functions or deduplication, and deterministic tie-breaking—by requiring derivation of first non-creator view times and per-creator collaborator counts from event tables.

    Coding & AlgorithmsTechnical Screen
  • FigureaiMediumData Engineer
    Build a Firmware Data Quality and Release-Feedback Framework

    This question tests the ability to design an end-to-end data pipeline architecture that ensures high-fidelity telemetry collection, automated quality validation, and safe release orchestration for embedded firmware devices.

    System DesignTechnical ScreenData EngineeringFirmwareObservability
  • FigureaiMediumData Engineer
    Choose a Metric Hierarchy for a Humanoid-Robot Fleet

    This problem tests the ability to structure a multi-layered metrics dashboard for complex hardware-software systems, balancing operational efficiency against safety and system stability.

    Analytics & ExperimentationTechnical ScreenMetricsData ModelingRobotics
  • FigureaiMediumData Engineer
    Design a Telemetry Platform Ingesting Two Gigabytes per Second

    This question tests your ability to design a high-throughput, fault-tolerant telemetry ingestion pipeline capable of handling high-velocity data streams from distributed robotic systems.

    System DesignTechnical ScreenData EngineeringScalabilityDistributed Systems
  • FigureaiMediumData Engineer
    Diagnose the Leading Cause of Slow or Failed Charging

    This problem tests your ability to define metrics from imperfect telemetry, perform root cause analysis on hardware failure, and design a strategy to identify performance bottlenecks in an autonomous charging system.

    Analytics & ExperimentationTechnical ScreenData EngineeringRoot Cause AnalysisTelemetry
  • GoogleMediumData Engineer
    Describe building and improving a dashboard

    Prepare a Google Data Engineer behavioral answer about building and improving a stakeholder dashboard. The solution covers business goals, KPI design, data validation, BI tooling, anomaly detection, root-cause analysis, feedback handling, and measurable impact.

    Behavioral & LeadershipTechnical Screen
  • GoogleMediumData Engineer
    User Activity Analytics: Unique Users per Activity and Average Time on Site

    This question evaluates a candidate's ability to process semi-structured event data using grouping, deduplication, and timestamp arithmetic in Python. It falls under coding and algorithms, commonly asked to assess practical data-wrangling skills such as aggregating per-key counts and computing time-based metrics while handling edge cases like unordered records and single-event users.

    Coding & AlgorithmsTechnical Screen
  • GoogleMediumData Engineer
    Write SQL and merge linked lists

    Solve a SQL customer order aggregation task and merge two sorted linked lists. The solution uses CTEs, window functions, LEFT JOINs, COALESCE, latest-order tie handling, optional returned-order filtering, and an O(m+n) dummy-head linked-list merge.

    Coding & AlgorithmsTechnical Screen
  • Interactive BrokersMediumData Engineer
    Compute Minimum Production Days

    A data engineering coding screen on greedy scheduling under a cooldown constraint: produce an ordered list of products, one per day, where each product type must cool down for `space` days before it can be produced again. Candidates must return the minimum number of days, ideally in O(n) time using a hash map of last-produced days.

    Coding & AlgorithmsTechnical Screen
  • Jain GlobalMediumData Engineer
    Build a Self-Service Market Data Discovery and Support Layer

    This problem tests your ability to design a robust metadata-driven orchestration layer that manages data lineage, access control, and quality monitoring for financial market datasets.

    Software Engineering FundamentalsTechnical ScreenSystem DesignData EngineeringMetadata
  • Jain GlobalMediumData Engineer
    Design an Incremental Rolling-Metrics Data Pipeline

    Design an incremental batch data pipeline to compute multi-horizon rolling financial metrics over daily ticker observations, handling bounded historical restatements, atomic publication, and data reconciliation.

    System DesignTechnical ScreenData EngineeringData PipelinesFinancial Data
  • Jain GlobalMediumData Engineer
    Design and Debug a Point-in-Time Backtest Data Pipeline

    This problem tests the ability to architect a robust financial data pipeline that ensures point-in-time accuracy and reproducible research.

    System DesignTechnical ScreenData EngineeringFinancial DataBacktesting
  • Jain GlobalMediumData Engineer
    Model Effective-Dated Compliance Restrictions for Securities

    This question tests the ability to design a time-series database schema capable of handling bitemporal data, identifier changes, and overlapping compliance restrictions.

    System DesignTechnical ScreenData ModelingTime-SeriesBitemporal
  • LinkedInMediumData Engineer
    Implement a stack supporting max and popMax

    This question evaluates understanding of data structures and algorithmic complexity, focusing on designing a stack variant that supports efficient retrieval and removal of the current maximum while preserving stack behavior.

    Coding & AlgorithmsTechnical Screen
  • MetaHardData Engineer
    Compute Max Score From Up to 3 Categories

    This Coding & Algorithms question in the Data Engineer domain evaluates grouping and top‑k aggregation concepts, testing the ability to combine per-category aggregation with selection under a uniqueness constraint.

    Coding & AlgorithmsTechnical Screen
  • MetaMediumData Engineer
    Compute capacities after site closures

    This question evaluates a candidate's ability to manipulate nested dictionary data structures and perform aggregate capacity computations, assessing data transformation, mapping, and set-based reasoning skills relevant to a Data Engineer within the Coding & Algorithms domain.

    Coding & AlgorithmsTechnical Screen