SUM OVER: Calculate Running Total of Daily Sales

SQL coding challenge · Difficulty: easy · +50 XP

Problem

The sales dashboard shows a running total alongside each transaction so the team can see cumulative revenue growing throughout the day.

Tables

Table: daily_sales

| sale_id | day_name | amount |
| 1 | Mon | 100 |
| 2 | Tue | 200 |
| 3 | Wed | 300 |
| 4 | Thu | 400 |
| 5 | Fri | 500 |

Expected Output

| sale_id | day_name | amount | running_total |
| 1 | Mon | 100 | 100 |
| 2 | Tue | 200 | 300 |
| 3 | Wed | 300 | 600 |
| 4 | Thu | 400 | 1000 |
| 5 | Fri | 500 | 1500 |

• Return: sale_id, day_name, amount, running_total
• Running total = sum of all rows up to and including current row
• Sort by sale_id ascending
• Function to use: SUM() OVER (ORDER BY sale_id)