sql SUM()函数 求和实例教程,好了下面来看看吧.
sum是用来求一列的数据之和的,必须是数值型的哦.下面来看看语法吧.
SELECT SUM(column_name) FROM table_name
我们举个例子来说明一下吧.
| O_Id | OrderDate | OrderPrice | Customer |
|---|
| 1 | 2008/11/12 | 1000 | Hansen |
| 2 | 2008/10/23 | 1600 | Nilsen |
| 3 | 2008/09/02 | 700 | Hansen |
| 4 | 2008/09/03 | 300 | Hansen |
| 5 | 2008/08/30 | 2000 | Jensen |
| 6 | 2008/10/04 | 100 | Nilsen |
SELECT SUM(OrderPrice) AS OrderTotal FROM Orders
结果为.5700
