题解 | #计salary累计和running_total#
统计salary的累计和running_total
https://www.nowcoder.com/practice/58824cd644ea47d7b2b670c506a159a6
select emp_no, salary, sum(salary)over(order by emp_no) running_total from salaries where to_date = '9999-01-01' order by emp_no