Practice SQL Window Functions – Free Exercises for Data Interviews

Practice 80 hand-crafted SQL problems focused entirely on window functions, all free of charge. Many challenges require CTEs.
Solve them all to restore glory to Xorthax's Galactic Trading Post.

PracticeWindowFunctions.com is a free platform to learn and practice SQL window functions through hands-on challenges. Perfect for interview preparation, our SQL window function exercises cover ROW_NUMBER(), RANK(), LEAD(), LAG(), NTILE(), and more. Each problem includes hints and solutions to help you master advanced SQL techniques.

📚 What You’ll Learn

Work with ranking functions, compare rows with LEAD and LAG, explore FIRST/LAST/NTH value lookups, and tackle advanced patterns like gaps and islands. Everything is focused on SQL window functions.

🧪 Try the Problems

1. Galactic Customer Revenue Breakdown
2. The Interstellar Sales Tracker 9000
3. Top 5 Spenders in the Galactic Bazaar
4. Two Orders Before, Two Orders After: The Price Prophecy
5. Customer Spending, Averaged and Analyzed
6. How Much More Did They Order?
7. Species Spending Champions
8. Five Transaction Trail Tracker
9. Lowest Deals in the Galaxy
10. The Galactic Max Order Hunt
11. The Largest Order in the Galaxy
12. Interstellar Spending Sprees
13. Order Volume, Customer by Customer
14. Currency Trends in 7-Order Windows
15. Champions of Loyalty
16. 30 Days of Distinct Artifacts
17. Order by Order, One by One
18. The First Transaction Initiative
19. Top Suppliers of the Trade Federation
20. Species Revenue Rankings
21. The Peak Stock Protocol
22. Clone Order Detector
23. Top 3 Galactic Bestsellers
24. Species Spending Standings
25. Most Popular Products in the Galaxy
26. Supplier Showdown
27. 5-Transaction Tally Tracker
28. Species Revenue Leaderboard
29. Category Revenue Rankings
30. Order Titans of the Stars
31. Category Spend Royalty
32. First Contact by Category
33. Galactic Spending Tiers
34. Five Tiers of Product Fame
35. Customer Frequency Classes
36. Stock Level Stratification
37. Supplier Pricing Pyramid
38. Species-Based Order Tiers
39. The Rare and the Profitable
40. Species Revenue Classifications
41. The First Order Ever Placed
42. Species Transaction Origins
43. The Pioneer Product in Every Category
44. Loyalty Group Order Milestones
45. The Final Purchase Report
46. The Final Product per Category
47. Species Transaction Wrap-Up
48. Last Fulfillments by Supplier
49. The Second Order Chronicles
50. Almost Famous: Second Place Products
51. The Bronze Revenue Medalists
52. The Fifth Fulfillment
53. The Next Order Countdown
54. Product Pairs in Category Time
55. Future Funds Forecast
56. Species Spending, Shift by Shift
57. Order Histories, One Step Back
58. Reverse Product Lineage
59. Two Transactions Ago...
60. Payment Patterns Revealed
61. Percent Rank: Species Spending Edition
62. Relative Product Popularity
63. Transaction Percentile Tracker
64. Supplier Pricing Percentiles
65. Cumulative Spending by Species
66. Cumulative Category Climb
67. Supplier Price Curves
68. Customer Revenue Trajectory
69. Category Spending Footprint
70. Supplier Performance Matrix
71. Species Revenue Surge
72. Rolling Sales by Category
73. Transaction Trail Analysis
74. Inventory Stack Ranks
75. Order Cadence Explorer
76. Unbroken Chains of Loyalty
77. Deserts of Silence
78. Constellations of Consistency
79. The Waning Moon of Commerce
80. The Merchant’s Marathon