今天群里有人問了個問題是這樣的：

復制代碼 代碼如下:

select name,sum(case when stype=4 then money*(-1) else money end ) as M
from table
group by name

復制代碼 代碼如下:

select name,sum(money*IF(stype=4,-1,1)) as M
from table
group by name