题解 | #统计salary的累计和running_total#
统计salary的累计和running_total
http://www.nowcoder.com/practice/58824cd644ea47d7b2b670c506a159a6
直接利用窗口函数解决!
求累计和/汇总 语句结构:SUM( 列名 )OVER( ORDER BY 列名)
select a.emp_no,a.salary, sum(a.salary) over(order by a.emp_no) as running_total from salaries a where a.to_date = '9999-01-01';