Cumulative cash flows
Question
Suppose you're given the following table showing daily cash flows for a business:
Table: cash_flows
| day | cash_flow |
|---|---|
| 1 | 1000 |
| 2 | -300 |
| 3 | 1200 |
| 4 | 1500 |
| 5 | -2000 |
| 6 | 700 |
| 7 | 650 |
| 8 | 900 |
Given the above table, write a SQL query to return the cumulative cash flow by day for the company.
For example, by day 3 your table should show 1900 (1000-300+1200) as the value.
You can view/query this table in an interactive SQL fiddle here.