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7-Day Rolling Revenue Average
Calculate a 7-day rolling average of daily revenue to smooth noise. First aggregate to daily revenue, then compute: day, daily_revenue, and rolling_7day_avg (average of current day + up to 6 preceding days, rounded to 2 dec). Sort by day. The first 6 rows will naturally have smaller windows — that is expected.
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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: Each day with its rolling 7-day average revenue
Hint
Concepts
SELECT Window Functions CTE Frame Clause GROUP BY
Practise the topic: SQL practice questions · Window function practice · CTE practice · GROUP BY exercises · Advanced SQL interview questions
Read the concept: SQL running total
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