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Coding questions
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Coding questions · Meta
Write SQL for 7-day WhatsApp call metrics
This question evaluates SQL-based data manipulation and aggregation skills, specifically time-based grouping, filtering by user attributes, deduplication, handling of edge-case durations, and computation of rates and medians from transactional call and event tables.
Coding questions · Uber
Write SQL for active counts and YTD top driver
This question evaluates a data scientist's SQL competency in aggregation, joins, time zone–aware datetime conversion, filtering on trip status, handling negative fares and zero-value drivers, tie-breaking, and the comparative use of window functions versus GROUP BY for ranking.
Coding questions · Meta
Write SQL for active follow connections
This question evaluates proficiency in temporal event modeling, time-aware SQL aggregation, and reasoning about state transitions from ordered event streams, testing competencies in building point-in-time and historical views within the Data Manipulation (SQL/Python) domain for data engineering roles, with a primary level of practical application augmented by temporal-conceptual understanding. It is commonly asked to assess the ability to infer current and daily historical relationships from event histories, manage edge cases like multiple request/accept cycles and rejections, and produce efficient queries for current counts and daily snapshots.
Coding questions · Roblox
Write SQL for ads metrics and variability
This question evaluates a candidate's ability to perform SQL-based data manipulation and analytics, including deduplication of events, computation of daily and campaign-level metrics (CTR, CPC), and calculation of statistical summaries (mean and standard deviation) and outlier detection over a specified date range.
Coding questions · Nextdoor
Write SQL for app metrics
This question evaluates proficiency in SQL-based data engineering, focusing on time-zone-aware timestamp handling, aggregation of event and relationship data, cohort retention analysis, and computation of product metrics like DAU, new users, photo activity, and follower distributions.
Coding questions · Meta
Write SQL for call analytics
This question evaluates a candidate's ability to perform SQL-based data manipulation and analytics, testing skills such as aggregations, joins to user metadata, percentage/rate calculations, and distinct-count reasoning over call records.
Coding questions · Character.AI
Write SQL for character safety and engagement metrics
This question evaluates proficiency in SQL-based data manipulation and analytics, specifically aggregations, joins, date-based grouping, ratio calculations, and windowed moving averages to compute safety and engagement metrics.
Coding questions · OneMain Financial
Write SQL for cohort retention and ARPU
This question evaluates a candidate's ability to perform time-based cohort analysis, compute D30 retention and 30-day ARPU, deduplicate exact event duplicates, and handle late or erroneous events using SQL.
Coding questions · Meta
Write SQL for comment analytics
This question evaluates proficiency in SQL analytics, specifically joins, filtering, aggregation (distinct counts), percentile functions, time-windowed grouping, handling soft-deleted records, and writing efficient queries via CTEs.
Coding questions · The New York Times
Write SQL for content-view analytics
This question evaluates proficiency in SQL-based data manipulation and analytics, including aggregation, distinct counting, NULL handling, timestamp/hour extraction, device grouping, and row-level ordering, and is situated in the Data Manipulation (SQL/Python) domain.
Coding questions · DoorDash
Write SQL for cuisine median delivery times
This question evaluates SQL proficiency in computing cuisine-level delivery performance metrics, including time-window filtering, joins, window/percentile functions for median aggregation, null handling, and percent-change calculations.
Coding questions · Meta
Write SQL for daily chats and fast replies
This question evaluates a candidate's ability to manipulate relational data and reason about temporal event sequences, specifically testing skills in SQL aggregation, distinct counting, deduplication, bidirectional relationship handling, and time-windowed event matching.
Coding questions · Netflix
Write SQL for DAU and first-purchase conversion
This question evaluates a candidate's practical SQL and data manipulation skills, including aggregations, distinct counts, joins, date-range handling, and identification of first-time purchases for conversion metrics.
Coding questions · CVS Health
Write SQL for dedup and purchase shares
This question evaluates proficiency in SQL data manipulation skills including entity deduplication, canonicalization rules, window functions, common table expressions, joins, and aggregation to derive per-user purchase counts and distributions.
Coding questions · DoorDash
Write SQL for deliveries analytics
This question evaluates SQL data manipulation and analytics skills—specifically aggregation, conditional counting, time-window filtering, joins, and handling of nulls and zero-count periods.
Coding questions · Meta
Write SQL for engagement and attribution KPIs
This question evaluates SQL data-manipulation skills for engagement and attribution KPIs, including joins, time-window (24-hour) analysis, deduplication of event data, conditional aggregation, and correct denominator construction for rate metrics.
Coding questions · Uber
Write SQL for fares and age-band counts
This question evaluates SQL competencies in aggregation, filtering, joins, numeric formatting, and precise date-based age calculation, including handling NULL fares, canceled trips, leap-year birthdays, and boundary-age cases.
Coding questions · TikTok
Write SQL for geo posting-frequency drops
This question evaluates proficiency in SQL-based time-series data manipulation, including time zone–aware date normalization, window functions, aggregation, filtering and median computations within the Data Manipulation (SQL/Python) domain.
Coding questions · Meta
Write SQL for hashtag analytics and joins
This question evaluates SQL data manipulation skills including join semantics (LEFT vs INNER), deduplicated aggregations, time-window filtering, ranking/tie-breaking, and recommendation logic for computing unique viewers, CTRs, and post-level hashtag suggestions.
Coding questions · Meta
Write SQL for hashtag source and safety rates
This question evaluates SQL data-manipulation competencies such as deduplication, date filtering, aggregations and ranking, handling missing foreign-key references, and calculating percentages from event and reference tables.
Coding questions · Roblox
Write SQL for influence score and follower growth
This question evaluates SQL data manipulation competencies such as joins, aggregations, distinct counts, window functions, and time-based grouping for computing an influence score (engagements on a user's posts plus follower count) and monthly follower growth, and it falls under Data Manipulation (SQL/Python).
Coding questions · Meta
Write SQL for initiators and French DAU%
This question evaluates SQL proficiency for time-based event analysis, covering joins, deduplication, CTEs, date/time and timezone handling, and aggregated metric calculation such as DAU and participation rates.
Coding questions · TikTok
Write SQL for last-7-day metrics without windows
This question evaluates proficiency in ANSI SQL data manipulation, including aggregation, de-duplication, date arithmetic, joins and subqueries, GROUP BY/HAVING usage, and cohort/retention and conversion calculations performed without window functions.
Coding questions · Meta
Write 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.