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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 1–23 of 23 results
- AgodaEasyData EngineerFind the Longest Calendar-Day Streak with All Employees Present
Identify dates when every employee is present and compute the longest consecutive streak, treating missing attendance as a gap.
Data Manipulation (SQL/Python)Technical Screen - AgodaEasyData EngineerRank Customers by Monthly Revenue with Competition Ties
Aggregate customer revenue by month and return top competition ranks, preserving tied totals and deterministic display order.
Data Manipulation (SQL/Python)Technical Screen - AgodaEasyData EngineerReturn Every Employee with a Mapped or Default Unique ID
Join employees to unique-ID mappings while preserving unmatched employees and applying an explicit fallback identifier.
Data Manipulation (SQL/Python)Technical Screen - AirbnbMediumData EngineerCalculate 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 EngineerEstimate 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 EngineerFind 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 EngineerFind 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 - BloombergMediumData EngineerWrite PostgreSQL string-manipulation query
This question evaluates proficiency in PostgreSQL string manipulation, regular expressions, URL parsing, key-value parsing and timestamp-based filtering for data transformation tasks.
Data Manipulation (SQL/Python)Technical Screen - ByteDanceMediumData EngineerModel Data for Analytics, Reporting, and Applications
Tests your ability to process raw semi-structured event logs into a clean, dimensional metric table suitable for downstream analytics and reporting.
Data Manipulation (SQL/Python)HR ScreenData ManipulationData ModelingPython - ClickhouseMediumData EngineerAnswer 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 - MetaMediumData EngineerCompute reservation diff for largest member
This question evaluates competency in relational data manipulation and aggregation using SQL or Python, including joins, grouping, and handling missing referrer relationships.
Data Manipulation (SQL/Python)Technical Screen - MetaMediumData EngineerRecommend 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 EngineerReturn count and renewal percentage of unreturned good copies
This question evaluates proficiency in SQL data manipulation, including conditional filtering, NULL handling, aggregation, and computing conditional percentages across related tables.
Data Manipulation (SQL/Python)Technical Screen - MetaMediumData EngineerReturn 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 EngineerSolve Python and SQL data tasks
This question evaluates data manipulation and engineering competencies by testing Python proficiency with nested data structure handling, complexity analysis and test-case design, alongside SQL proficiency in UTC-aware aggregation and per-user deduplication to compute daily active users; it is categorized as Data Manipulation (SQL/Python) within the data engineering domain. Such problems are commonly asked to assess practical implementation ability and robustness under edge cases, as well as conceptual understanding of time/space complexity and correct date-time handling, reflecting a primarily practical application with elements of conceptual analysis.
Data Manipulation (SQL/Python)Technical Screen - MetaMediumData EngineerWrite SQL for library analytics
This question evaluates proficiency in SQL-based data manipulation and analytical querying, focusing on relational schema navigation, joins, aggregation, filtering, and handling temporal and conditional metrics within a library dataset.
Data Manipulation (SQL/Python)Technical Screen - NuroEasyData EngineerCompute unique duration by merging intervals
This question evaluates a data engineer's proficiency in temporal data manipulation and interval-set reasoning using SQL and Python, specifically skills in merging overlapping intervals and computing deduplicated cumulative durations.
Data Manipulation (SQL/Python)Technical Screen - Otter.AiMediumData EngineerFind Every Project with the Most Employees
Build a PostgreSQL aggregation that returns every project tied for the largest employee count. This compact exercise checks grouping, maximum selection, tie preservation, empty-input behavior, and careful use of primary-key guarantees.
Data Manipulation (SQL/Python)Technical Screen - Otter.AiMediumData EngineerFind the Highest-Paid Employee in Each Department
Work through a tie-aware PostgreSQL problem that finds every highest-paid employee in each department. It assesses relational reasoning, correct joins, duplicate-name handling, and precise output semantics without assuming a single winner.
Data Manipulation (SQL/Python)Technical Screen - RbcroyalbankEasyData EngineerExplain pandas and SQL basics
This question evaluates familiarity with pandas data structures (Series vs DataFrame), SQL filtering semantics (WHERE vs HAVING), and practical SQL aggregation for detecting duplicate records, assessing competencies in data manipulation, aggregation, and basic data quality checks.
Data Manipulation (SQL/Python)Technical Screen - TikTokMediumData EngineerDebug a Hive Query for DAU
This question evaluates proficiency in Hive/SQL query formulation, data partitioning and pruning, join and aggregation semantics, timestamp handling, and performance tuning for large-scale analytics.
Data Manipulation (SQL/Python)Technical Screen - TikTokMediumData EngineerDebug a Hive insert query
This question evaluates a candidate's ability to debug Hive INSERT/SELECT operations, focusing on schema and column alignment, data types and casts, partition handling, file formats/SerDe, ACID/transactional constraints, and syntax or reserved keyword issues.
Data Manipulation (SQL/Python)Technical Screen - TikTokMediumData EngineerExplain a SQL query result
This question evaluates proficiency in SQL result-set interpretation and reasoning about joins, filters, aggregations, window functions, NULL handling, duplicate rows, and ordering within the Data Manipulation (SQL/Python) domain for a Data Engineer role.
Data Manipulation (SQL/Python)Technical Screen
Agoda
Airbnb
Bloomberg
Meta
Nuro
Otter.Ai
TikTok