如何在MySql中获取值的总和

Question

I have got Table:

id        name      amount
--------------------------
1         abc       1
2         abc       2
3         abc       -3
4         def       4

I want to get sum of every amounts of name==abc, i mean 1+2+(-3) = 0;

How to do this in MySql?

Answer 1

SELECT SUM(amount) FROM table WHERE name = 'abc';

Answer 2

不确定mySQL，但是“标准” SQL将是：

select sum(amount) from yourTableName where name='abc'

Answer 3

SELECT SUM(amount) AS total FROM table WHERE name = 'abc'

Answer 4

SELECT name, SUM(amount) from Table GROUP BY name;

Answer 5

SELECT SUM(amount)
FROM tableName
WHERE name='abc'