READ. UNDERSTAND. PRACTICE.
Prepare for your next interview.
Explore algorithm tutorials, coding and system design questions, interview experiences, and computer science study guides.
20,926 resources · Page 94 of 872
Coding questions · Additive Ai
Advance Game of Life with Reduced Auxiliary Storage
Advance Game of Life by one generation while preserving simultaneous updates, handling grid boundaries, and reducing storage in an in-place implementation.
Coding questions · Netflix
Aggregate D1 retention cohorts in SQL
This question evaluates a candidate's competency in time-series cohort analysis and SQL-based data manipulation, specifically measuring DAU, new-user cohorts, D1 retention and revenue-per-user while handling deduplication and user filtering.
Coding questions · Capital One
Aggregate exam scores with NULL handling
This question evaluates proficiency in SQL data manipulation, specifically joins (including LEFT JOIN behavior), NULL handling with ISNULL/COALESCE, conditional aggregation, distinct counts, and date-based filtering within the Data Manipulation (SQL/Python) domain, focusing on practical application of query-writing skills.
Coding questions · Rippling
Aggregate expenses by person, trip, and category
This question evaluates a candidate's ability to perform efficient data aggregation, use associative data structures (maps/dictionaries), and reason about time and space complexity when processing large collections of records.
Coding questions · Meta
Aggregate Netflix metrics in SQL
This question evaluates a candidate's proficiency in SQL data aggregation and construction of cumulative metrics for streaming analytics, including handling alignment of records when identifiers may appear in only one dataset.
Coding questions · CVS Health
Aggregate radiology spend and derive fiscal month
This question evaluates a candidate's competency in data manipulation and preprocessing using SQL/Python, covering robust dtype specification, null handling, numeric aggregation and percentage computation, datetime parsing, and fiscal-month derivation.
Coding questions · Mixpanel
Aggregate User Events and Check Join Uniqueness
Aggregate user events and retain all users in PostgreSQL, computing event count, distinct active dates, earliest event, and join uniqueness.
Coding questions · Robinhood
Aggregate user logs into 30-minute sessions
This question evaluates data engineering competencies in time-series sessionization, datetime parsing and arithmetic, grouping and aggregation, distinct-count computation, and CSV log processing.
Coding questions · Pinterest
Aggregate video time and unique pins in Python
This question evaluates competency in data aggregation, deduplication, and algorithmic efficiency by requiring computation of category-level averages with tie-breaking and per-user unique counts, demonstrating proficiency in Python and SQL-style data manipulation.
Coding questions · Instacart
Aggregate weekly revenue and attribute 4% drop
This question evaluates a candidate's ability to perform time-based revenue aggregation, filtering, percent-change calculation, and geo-level attribution using SQL or Python, with attention to ISO-week alignment and revenue computation.
Coding questions · Harvey
Allocate Unique File Names in an In-Memory Vault
Allocate unique vault file names with the smallest available numeric suffix, handling preexisting suffixes, repeated requests, and case sensitivity.
Coding questions · Chime
Analyze Acquisition Channels for User Value and Retention
This question evaluates proficiency in SQL/Python data manipulation and analytics, testing aggregation, cohort and retention analysis, ranking, joins and window-function usage along with interpretation of user-level revenue metrics.
Coding questions · Meta
Analyze Ad CTR and Convert Transactions to USD
This question evaluates proficiency in calculating and ranking per-user ad click-through rates and normalizing transaction amounts across currencies, testing competencies in aggregation, ranking logic, temporal joins, and currency conversion.
Coding questions · TikTok
Analyze and Clean European Ecommerce Sales Data
This question evaluates proficiency in data manipulation and analysis with Pandas, covering time-window filtering, regional subsetting, deduplication, missing-value handling, aggregation, and visual summarization.
Coding questions · Meta
Analyze Bookstore Data to Identify Top Payment Methods
This question evaluates data manipulation and analytical SQL/Python competency, focusing on relational joins, aggregations, string filtering, ranking, and proportion calculations across multiple tables in a bookstore schema.
Coding questions · Meta
Analyze Conversation Engagement and Reaction Usage Effectively
This question evaluates data manipulation and analytical skills in SQL and Python, focusing on deduplication of unordered sender-receiver pairs, temporal aggregation and differences, computation of counts and percentages, and the design of query-friendly engagement metrics.
Coding questions · Meta
Analyze Cross-Country Call Data for Recent Trends
This question evaluates a candidate's competency in relational data manipulation, including joining tables, aggregations, time-based filtering, and duration calculations using SQL or equivalent Python tools.
Coding questions · DoorDash
Analyze Customer Purchase Patterns Using SQL Query
This question evaluates a candidate's competence with SQL data manipulation and windowing concepts, specifically using ordering and partitioning to compare and rank events within a customer's purchase history.
Coding questions · Notion
Analyze document collaboration from CSV logs
This question evaluates data manipulation and analytical competencies—particularly deduplication, joins, aggregation, co-occurrence counting, and metric definition—applied to CSV access logs and user metadata.
Coding questions · DoorDash
Analyze Driver Requests for Food Delivery Orders
This question evaluates data manipulation and analytical SQL skills in the Data Manipulation (SQL/Python) domain, focusing on window functions for ranking and temporal comparison, joins, and aggregation when analyzing orders and driver requests.
Coding questions · Pinterest
Analyze Global Engagement and Impressions with SQL Queries
This question evaluates proficiency in SQL-based data manipulation and analytical querying, covering aggregation, grouping, ranking, and the correlation of impressions with user engagement and feature usage metrics.
Coding questions · Meta
Analyze Group Call Adoption Using SQL Queries
This question evaluates SQL data-manipulation and analytical skills, including aggregation, conditional counting, distinct counts, date-based grouping, and percentage calculations on event logs.
Coding questions · Meta
Analyze Hashtag Follow Behavior with SQL Queries
This question evaluates a candidate's competency in data manipulation and analytical SQL techniques—specifically aggregation, filtering, joins, and calculation of proportions—to analyze hashtag follow behavior.
Coding questions · Affirm
Analyze Loan Payments Using Pandas for Key Insights
This question evaluates data manipulation and aggregation skills using pandas, focusing on computing per-loan payment totals, payment success rates, and a repayment-status flag. It is commonly asked to assess applied data wrangling and numeric summarization abilities in the Data Manipulation (SQL/Python) domain, testing practical application rather than purely conceptual understanding.