SQL Quest › SQL Interview Questions › Aggregation & Grouping
Day-of-Week Order Pattern (strftime)
Operations wants to know which days of the week see the most orders — useful for staffing fulfillment shifts.
Use strftime('%w', order_date) to extract the day-of-week ('0' = Sunday, '6' = Saturday). Show dow (the digit) and order_count. Group by dow. Order by dow.
This is the simplest day-of-week bucketing — no JOINs to a calendar table, just the strftime trick. If you need human-readable day names, you'd add a CASE on top.
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Schema
orders
| order_id | customer_id | product | category | quantity | price | total | order_date | country | status |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 1 | Laptop Pro | Electronics | 1 | 1299.99 | 1299.99 | 2024-01-15 | USA | completed |
| 2 | 2 | Wireless Mouse | Electronics | 2 | 49.99 | 99.98 | 2024-01-16 | Canada | completed |
| 3 | 3 | Office Chair | Furniture | 1 | 349.99 | 349.99 | 2024-01-17 | USA | completed |
Expected output: 1 → 2, 3 → 1, 6 → 1
Hint
SELECT, GROUP BY, Date Functions, and open the hint there if you stall.Concepts
SELECT GROUP BY Date Functions strftime
Practise the topic: SQL practice questions · GROUP BY exercises · Date function practice
Read the concept: SQL GROUP BY tutorial
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