Getting a running total

Given this data:

date| amount |
—— | —— |
2016-03-12 | 200 |
2016-03-11 | -50 |
2016-03-14 | 100 |
2016-03-15 | 100 |
2016-03-10 | -250 |

SELECT date, amount, SUM(amount) OVER (ORDER BY date ASC) AS running
FROM operations
ORDER BY date ASC

will give you

date| amount | running
—— | —— | —–– |
2016-03-10 | -250 | -250 |
2016-03-11 | -50 | -300 |
2016-03-12 | 200 | -100 |
2016-03-14 | 100 | 0 |
2016-03-15 | 100 | -100 |