SQL百分比查询

Question

我是SQL的初学者，我的问题是关于从称为merged的表中计算所披露的总数的百分比。我想根据委员会的位置（合并表中的一列）计算“支持”的数量]

在这种情况下，如何计算百分比。我从开始：

SELECT Sum (amount) *100
from merged
where merged.committee_position == 'SUPPORT';

帮助我继续，谢谢

Answer 1

如果我正确地关注了您，则可以进行条件聚合：

select 
    100.0 * sum(case when committee_position = 'SUPPORT' then amount else 0 end) / sum(amount)
from merged

这将为您提供具有committee_position = 'SUPPORT'的金额占表中总额的百分比。

Answer 2

您在这里。

SELECT a.Support_Amount/b.Total_Amount*100
FROM (SELECT Sum (amount) as Support_Amount
from merged
where merged.committee_position = 'SUPPORT') as a
CROSS JOIN 
(SELECT Sum (amount) as Total_Amount
from merged) as b