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Coding questions

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1,899 resources · Page 76 of 80

Coding questions · Meta
Write advanced SQL for sales support analytics
This question evaluates practical SQL data-manipulation skills such as joins, aggregation, window functions, time-based filtering, deduplication, and computation of sales KPIs for rep-level analytics.
Coding questions · Thumbtack
Write complex joins and window functions
This question evaluates advanced SQL analytics skills including complex joins, window functions, ordered-set aggregates and percentile calculations, time/date arithmetic, grouping and dense-ranking for computing time-to-first-quote, top-N per category, and within-request price percentiles.
Coding questions · TikTok
Write complex SQL for cohorts and retention
This question evaluates advanced SQL and data-engineering competencies such as cohort and retention analysis, deduplication, timezone normalization, last-touch attribution, aggregate revenue calculations, and effective use of window functions in the Data Manipulation (SQL/Python) domain.
Coding questions · Disney
Write complex SQL for streaming funnels
This question evaluates a candidate's ability to write complex ANSI-SQL for event-level funnel analysis, including temporal windowing, user attribution, multi-stage aggregation, and handling of event schemas.
Coding questions · DoorDash
Write complex SQL on DoorDash data
This question evaluates proficiency in complex SQL querying and data manipulation, including joins across tables, time-based filtering, window functions, null and edge-case handling, aggregations, and integrating promotion and order-event data.
Coding questions · PayPal
Write conditional aggregation SQL queries
This question evaluates proficiency with conditional aggregation in SQL, including the use of SUM(CASE WHEN ...) versus filtering with WHERE and the implications of placing aggregation filters in HAVING for grouped queries, within the Data Manipulation (SQL/Python) domain.
Coding questions · Block (Square)
Write left-join queries with tricky filters
This question evaluates SQL data-manipulation skills including LEFT JOIN semantics, aggregation functions like COUNT(DISTINCT) and SUM, GROUP BY/HAVING logic, and date-window filtering for referral and order analytics.
Coding questions · Thumbtack
Write monthly new-vs-returning requests SQL
This question evaluates a candidate's ability to perform time-based SQL aggregation and classification, covering window functions to compute each user's first request month, conditional counts for NEW vs RETURNING requests, percentage formatting, and correct handling of UTC timestamps and edge cases.
Coding questions · Upstart
Write monthly touches and last-touch SQL
This question evaluates proficiency in SQL-based data manipulation and time-based attribution, covering aggregations, joins, window functions, date truncation to calendar months, tie-breaking logic, and handling edge cases like post-conversion touches and duplicate timestamps.
Coding questions · Capital One
Write one SQL for exam scores aggregation
This question evaluates proficiency in SQL data manipulation and reporting, specifically joins, GROUP BY and aggregate functions, NULL handling (COALESCE/ISNULL), conditional aggregation and set operations to produce combined result sets.
Coding questions · Bloomberg
Write Postgres string parsing and aggregation query
This question evaluates proficiency in SQL string parsing and regular expressions, type casting to timestamps, date-based filtering, distinct aggregation, and awareness of cross-dialect function equivalence, and is categorized under Data Manipulation (SQL/Python) and database querying.
Coding questions · Bloomberg
Write 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.
Coding questions · Circle
Write PostgreSQL updates with date filters
This question evaluates competency in PostgreSQL data manipulation, covering updates with correct timestamp handling, upserts with conflict resolution, date-range selection using timestamptz, and index design plus performance analysis with EXPLAIN ANALYZE.
Coding questions · Apple
Write queries to compute salary and budget stats
This set of tasks evaluates data manipulation and analytical competencies, specifically the ability to compute order-statistics on numeric columns, perform relational joins to enrich event records, and reason about constrained selection for maximizing hires using SQL and pandas.
Coding questions · Twitch
Write robust SQL for streaming analytics
This question evaluates a candidate's ability to author robust SQL for streaming analytics, covering de-duplication, event-time handling, sessionization, concurrency, overlap detection, and retention calculations on time-series view event data.
Coding questions · Chime
Write rolling-window SQL over weekly cohorts
This question evaluates proficiency with SQL window functions and CTEs for time-based cohort aggregation, including rolling ROWS-based sums, LAG-based week-over-week percent change, DENSE_RANK ranking, and handling first- and second-purchase calculations.
Coding questions · Pinterest
Write SQL and pandas for shopping events
This question evaluates a candidate's ability to perform data manipulation in SQL and pandas, covering event deduplication, time-window aggregations, next-day retention calculations, top-N ranking, joins, and data cleaning/mapping for analytics.
Coding questions · Uber
Write SQL and Pandas for Uber Trips
This question evaluates SQL and Pandas data manipulation competencies, including joins, time-based filtering, handling NULLs, aggregations, rate and ratio calculations, and windowed comparisons over grouped city-day data.
Coding questions · Meta
Write SQL and Python for data prep
This question evaluates data engineering competencies including SQL analytics with window functions and MERGE/INSERT patterns for idempotent incremental jobs, event-time handling (duplicates and late events), sessionization and retention metrics, plus Python-based JSON parsing, normalization, partitioned Parquet output and basic unit testing.
Coding questions · Coinbase
Write SQL and Python for funnels/retention
This question evaluates SQL and Python data-manipulation skills, including event-to-session joins, temporal window filtering, deduplication, JSON metadata handling, and computation of funnel and retention metrics like daily unique users and conversion rates.
Coding questions · Robinhood
Write SQL and Python for transaction analytics
This question evaluates data manipulation competency in SQL and Python, covering normalization of transaction direction, JOINs and CASE logic, window functions for ranking and aggregation, and designing single-pass counting algorithms for streaming-like inputs.
Coding questions · Meta
Write SQL filtering, grouping, CASE, UNION tasks
This question evaluates proficiency with SQL filtering, aggregation, conditional logic, and set operations—specifically skills around WHERE filtering, GROUP BY/HAVING, CASE bucketing, FLOOR on aggregates, and UNION versus UNION ALL—within the Data Manipulation (SQL/Python) domain and emphasizes practical application of ANSI SQL.
Coding questions · Coinbase
Write SQL for 30-day activity and D7 retention
This question evaluates a candidate's skill in SQL-based data manipulation and product-analytics competencies—specifically aggregation, deduplication to avoid double-counting, date arithmetic for time-windowed queries, cohort retention calculation, and percentage metrics—in the Data Manipulation (SQL/Python) domain.
Coding questions · TikTok
Write SQL for 7-day geo-localized revenue dashboard
This question evaluates SQL skills in time-zone aware local-date aggregation, idempotent event deduplication, cohorting for new versus returning users, calculation of revenue and conversion metrics, and anomaly detection via median-based drop flags.