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Tracks/Joins

Joins

Combine rows across tables, including self-joins.

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INNER JOIN
LEFT JOIN
RIGHT JOIN
FULL OUTER JOIN
CROSS JOIN
self join

0/49 solved

  1. 1—005. Employees With Departments
    easy
  2. 2—016. Employees With No Department
    easy
  3. 3—021. Coalesce Missing Department Name
    easy
  4. 4—143. Use Table Aliases in a JOIN
    easy
  5. 5—145. Join Orders with Customer Details
    easy
  6. 6—146. Find Customers Who Have Never Ordered
    easy
  7. 7—303. Find Employees in a Named Department
    easy
  8. 8—325. All Departments Including Those with No Employees
    easy
  9. 9—326. Generate All Month–Category Combinations
    easy
  10. 10—037. Products Never Ordered
    medium
  11. 11—039. Manager Names via Self Join
    medium
  12. 12—040. Order Line Details
    medium
  13. 13—048. All Employees and Departments (Full Outer Join)
    medium
  14. 14—049. All Size-Color Combinations (Cross Join)
    medium
  15. 15—060. Employees Sharing the Same Salary
    medium
  16. 16—062. Products with Above-Average Rating
    medium
  17. 17—070. Products with Zero Total Sales
    medium
  18. 18—072. Customer Lifetime Value
    medium
  19. 19—085. Employees Who Share the Same Manager
    medium
  20. 20—086. All Departments Including Empty Ones
    medium
  21. 21—178. Traverse Org Chart Hierarchy with Recursive CTE
    medium
  22. 22—190. Fill Date Gaps Using GENERATE_SERIES
    medium
  23. 23—199. Show Each Employee with Their Manager's Name
    medium
  24. 24—200. Order Details with Customer and Product Names
    medium
  25. 25—201. Four-Table JOIN with Category Filter
    medium
  26. 26—202. Find Customers Who Have Never Placed an Order
    medium
  27. 27—203. All Product Color and Size Combinations Using CROSS JOIN
    medium
  28. 28—209. Month-2 Retention Rate Calculation
    medium
  29. 29—252. Product Co-Purchase Analysis
    medium
  30. 30—262. Comparing Two Datasets with FULL OUTER JOIN
    medium
  31. 31—264. Rolling 30-Day Distinct Customer Count
    medium
  32. 32—270. Detect Overlapping Date Ranges
    medium
  33. 33—277. Employees Promoted in the Last 6 Months
    medium
  34. 34—337. Order Items With No Discount Applied
    medium
  35. 35—348. Employee vs Manager Salary Gap
    medium
  36. 36—355. Employees Sharing at Least One Project
    medium
  37. 37—368. Product Co-Purchase Affinity Score
    medium
  38. 38—369. Manager Span of Control (Direct Reports Count)
    medium
  39. 39—378. Product Revenue Contribution via CTE
    medium
  40. 40—091. Managers Paid Above Team Average
    hard
  41. 41—098. Frequently Bought Together (Market Basket)
    hard
  42. 42—281. Recursive Bill of Materials Explosion
    hard
  43. 43—282. Full Org Chart Path as String
    hard
  44. 44—288. Time-Series Gap Filling with Zero Revenue Days
    hard
  45. 45—293. Fraud Detection: 3+ Transactions Within 1 Hour
    hard
  46. 46—296. Nearest Price Match Across Two Catalogs
    hard
  47. 47—383. Required Skills Missing per Employee
    hard
  48. 48—397. Nearest Neighbor by Euclidean Distance
    hard
  49. 49—400. Monthly Revenue and New-Customer Dashboard
    hard