Question

i 拥有类似表格

NAME    VALUE
-----------------
bla      1
bla      2
bla      2
bla      3
bla      1
bla      4
bla      2

How can i do a sum of ONLY different values , and ignore the repeating values (is it possible?)? Something like this :

 SELECT SUM(??condition?? value) as total FROM table

数额应为10。

谢谢!

Answer 1

这一工作应当:

SELECT SUM(value) as total FROM (SELECT DISTINCT value FROM table) tmp;

资料来源:

SELECT SUM(DISTINCT value) as total FROM table

第二种解决办法较好,因为它没有形成临时表格。因此,速度更快。

Answer 2

Would

SELECT SUM(DISTINCT value) FROM mytable;

trick?

Answer 3

如果你想总结所有不同的价值观,你可以使用数字清单。

SELECT SUM(DISTINCT value) AS total FROM yourtable

如果你想计算每个名字的一笔不同数额,则按以下方式增加:

SELECT name, SUM(DISTINCT value) AS total 
FROM yourtable
GROUP BY name

或者仅考虑具体名称:

SELECT SUM(DISTINCT value) AS total 
FROM yourtable
WHERE name =  bla