Data Manipulation (SQL/Python) Interview Questions

Showing 1–30 of 39 results

• AdobeMedium·Software Engineer
  Find Top-Funded Villages and Their Top Projects

  Tests the ability to write a multi-level SQL aggregation with window functions, exact date filtering, tie handling, and deterministic sorting.

  Data Manipulation (SQL/Python)Online Assessmentsqlwindow-functionsaggregation
• Akuna CapitalMedium·Software Engineer
  Answer SQL MCQs with reasoning

  This question evaluates proficiency in SQL query semantics and reasoning about relational operations—specifically INNER, LEFT, and RIGHT JOIN behavior; GROUP BY and HAVING usage; NULL handling in comparisons and aggregates; window functions such as ROW_NUMBER and RANK; and the logical query processing order—within the Data Manipulation (SQL/Python) domain. It is commonly asked to assess the ability to interpret and justify query outcomes versus alternative answers, testing both conceptual understanding of relational theory and practical application of SQL query behavior.

  Data Manipulation (SQL/Python)Online Assessment
• Akuna CapitalMedium·Software Engineer
  Evaluate SQL expressions for zero

  This question evaluates understanding of SQL type coercion, boolean semantics, comparison operators, and dialect-specific evaluation behavior (for example, MySQL), focusing on interpreting expressions that may evaluate to zero.

  Data Manipulation (SQL/Python)Online Assessment
• AmazonMedium·Data Scientist
  Diagnose MySQL joins and GROUP BY/HAVING errors

  This question evaluates mastery of SQL join semantics (LEFT, RIGHT, FULL OUTER emulation, CROSS), NULL equality and duplicate handling, GROUP BY/HAVING behavior under ONLY_FULL_GROUP_BY, aggregation result shaping and type/format conversions in the Data Manipulation (SQL/Python) domain.

  Data Manipulation (SQL/Python)Online Assessment
• Boston Consulting GroupMedium·Data Scientist
  Merge and Clean Customer Order Data for Analysis

  This question evaluates proficiency in data manipulation with pandas and SQL concepts, focusing on dataset merging, missing-value handling, and computing derived aggregate columns such as total_spent.

  Data Manipulation (SQL/Python)Online Assessment
• Boston Consulting GroupMedium·Data Scientist
  Merge and Concatenate Inconsistent Order Files with Pandas

  This question evaluates proficiency with pandas-based data manipulation, including schema alignment, column renaming, type casting, and vertical concatenation when merging CSV files.

  Data Manipulation (SQL/Python)Online Assessment
• CVS HealthMedium·Data Scientist
  Create Views, Insert, and Update Correctly

  This question evaluates SQL data-manipulation competencies including view creation, aggregate joins, INSERT/UPDATE operations, and reasoning about temporal effects on computed aggregates such as historical customer spend.

  Data Manipulation (SQL/Python)Online Assessment
• CVS HealthMedium·Data Scientist
  Create and query an e-commerce schema

  This question evaluates SQL schema design and data manipulation competencies, including defining PostgreSQL table types and constraints, inserting exact datasets, composing aggregate and join queries with date-based filters, and performing DML updates with verification.

  Data Manipulation (SQL/Python)Online Assessment
• Capital OneMedium·Data Scientist
  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.

  Data Manipulation (SQL/Python)Online Assessment
• Capital OneEasy·Data Analyst
  Analyze Mission Outcomes and Allocate Response Units

  Analyze incident response records to calculate unit win rates, evaluate the impact of rest periods on success, and rank response units using tie-breakers.

  Data Manipulation (SQL/Python)Online AssessmentPythonData ManipulationAnalytics
• Capital OneMedium·Data Scientist
  Find top category per region in Aug 2025

  This question evaluates proficiency in SQL data manipulation skills such as joining related tables, aggregating revenue, filtering by date and status, and implementing deterministic tie-breaking for categories.

  Data Manipulation (SQL/Python)Online Assessment
• Capital OneMedium·Data Scientist
  Fix dash dates and aggregate watch time

  This question evaluates data-cleaning and aggregation competencies, focusing on handling nonstandard missing-date markers, forward-filling in spreadsheets, correct date-range filtering, pivot-table summarization, and concise pandas grouping and aggregation.

  Data Manipulation (SQL/Python)Online Assessment
• Capital OneMedium·Data Scientist
  Merge CSVs and build revenue pivot with pandas

  This question evaluates proficiency in data manipulation and ETL using pandas, covering robust file I/O, join/merge semantics, null/coalescing behavior, date parsing, aggregation, and pivoting.

  Data Manipulation (SQL/Python)Online Assessment
• Capital OneMedium·Data Scientist
  Merge ad CSVs and compute CTR

  This question evaluates SQL data manipulation competencies such as cleaning and merging CSVs, forward-filling missing dates, correct multi-table joins without duplication, use of window functions, time-windowed aggregations, and computation of click-through rate (CTR).

  Data Manipulation (SQL/Python)Online Assessment
• CircleMedium·Software Engineer
  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.

  Data Manipulation (SQL/Python)Online Assessment
• DRWMedium·Machine Learning Engineer
  Process CSV for portfolio returns and metrics

  This question evaluates a candidate's competency in time-series data manipulation, financial return computation, portfolio analytics, numerical stability, modular software design (clear function boundaries and unit tests), and algorithmic complexity analysis within the Data Manipulation (SQL/Python) domain.

  Data Manipulation (SQL/Python)Online Assessment
• IBMMedium·Software Engineer
  Find Customers Whose Average Website Resource Usage Exceeds 50 Percent

  Practice PostgreSQL aggregation with HAVING, customer-level average resource utilization, strict thresholds, two-decimal rounding, and ascending email output.

  Data Manipulation (SQL/Python)Online Assessment
• IBMEasy·Data Scientist
  Write SQL to compute max and min marks

  This question evaluates a candidate's ability to perform basic data aggregation in SQL, specifically computing summary statistics from a single table. It is commonly asked to assess competence in data manipulation and query result shaping within the Data Manipulation (SQL/Python) domain, focusing on practical application of SQL aggregation rather than purely conceptual theory.

  Data Manipulation (SQL/Python)Online Assessment
• KKneronMedium·Software Engineer
  Count IoT devices matching date and threshold

  This question evaluates handling of paginated REST APIs, JSON parsing and nested-data filtering, month/year date parsing, and numeric threshold comparisons, reflecting skills in data retrieval and programmatic data manipulation.

  Data Manipulation (SQL/Python)Online Assessment
• MathWorksMedium·Software Engineer
  Calculate cost from orders with SQL

  This question evaluates a candidate's ability to perform SQL data manipulation and business-rule calculations, including conditional joins, date-range filtering, and numeric arithmetic for discounts and taxes.

  Data Manipulation (SQL/Python)Online Assessment
• MillenniumMedium·Software Engineer
  Implement paginated API ingestion

  This question evaluates skills in API integration, paginated data ingestion, error handling with retries and exponential backoff, rate limiting, streaming CSV serialization without holding all records in memory, schema normalization, unit testing, and time/space complexity analysis.

  Data Manipulation (SQL/Python)Online Assessment
• NVIDIAMedium·Software Engineer
  Implement a Python test harness

  This interview question evaluates SQL or pandas logic, joins, grouping, window functions, null handling, edge cases, and validation in a realistic interview setting. A strong answer for Implement a Python test harness states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

  Data Manipulation (SQL/Python)Online Assessment
• OpenAIMedium·Data Scientist
  Design Schema and Logic for Subscription Event Tracking

  This question evaluates proficiency in event-driven data modeling, temporal state derivation, and implementation of SQL/Python logic to compute per-user subscription status and history within the Data Manipulation (SQL/Python) domain.

  Data Manipulation (SQL/Python)Online Assessment
• OpenAIMedium·Data Scientist
  Design Schema for Accurate Subscription State Tracking

  This question evaluates proficiency in temporal schema design and event-level data modeling, focusing on reconstructing time-varying subscription state using SQL and Python in the Data Manipulation (SQL/Python) domain.

  Data Manipulation (SQL/Python)Online Assessment
• OOtherMedium·Data Scientist
  Write SQL to analyze response accuracy and speed

  This question evaluates proficiency with SQL-based data manipulation and analytical querying on relational assessment data, including aggregation, grouping, joins, windowed ranking, and use of PostgreSQL statistical functions to analyze accuracy and response-time metrics.

  Data Manipulation (SQL/Python)Online Assessment
• OOthersEasy·Data Scientist
  Compute per-coin quarterly amounts and totals

  This question evaluates competence in SQL data manipulation—specifically time-based conditional aggregation, grouping, joins, and handling entities with no activity—to compute per-coin quarterly sums and year-to-date totals.

  Data Manipulation (SQL/Python)Online Assessment
• Point72Hard·Data Scientist
  Build the auction status table

  This problem tests advanced SQL skills, specifically the ability to perform window functions, handle state transitions, and aggregate time-series data to reconstruct the final status of entities.

  Data Manipulation (SQL/Python)Online AssessmentSQLWindow FunctionsData Aggregation
• RReevoMedium·Software Engineer
  Fetch and aggregate paginated team data via API

  This question evaluates API integration, pagination handling, robust error handling (retries/backoff and rate-limit awareness), data aggregation, sorting and top‑N selection skills within the Data Manipulation (SQL/Python) domain.

  Data Manipulation (SQL/Python)Online Assessment
• StripeMedium·Data Scientist
  Write SQL to detect recurring non-subscription users

  This question evaluates a candidate's ability to perform advanced SQL data manipulation and temporal pattern detection in transactional datasets, including attribute-based matching (amount and card fingerprint) and filtering by transaction status.

  Data Manipulation (SQL/Python)Online Assessment
• TikTokMedium·Data Scientist
  Count buggy vs non-buggy by employer

  This question evaluates proficiency in SQL data manipulation—particularly conditional aggregation and join semantics—for counting categorized records across related tables in a data science context.

  Data Manipulation (SQL/Python)Online Assessment