作者nosezhao (赏月亮一巴掌)
站内Database
标题Re: [SQL ] 请问计算得票率...?
时间Wed Apr 25 21:31:47 2007
※ 引述《SmallBeeWayn (喵喵叫的蜜蜂猫)》之铭言：
: 系统: MySQL 4.1 & PHP 5
: 资料库大致呈现这个形式
: 也就是说计算出每个人在每个Round的RV => (Votes/(同个Round的SUM))
没有实际验证，或许需要修改
Method 1.
select a.Name , a.Round , (a.Votes/b.T_Votes)
from db as a,(
select Round,sum(Votes) as T_Votes from db group by Round
) as b
where a.Round=b.Round
Method 2.
select X.Name , X.Round ,
X.Votes/(select sum(Y.Votes) from db as Y where Y.Round=X.Round )
from db as X
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