用sql计算比率

我正在使用Hiveql查询预处理一些原始数据。在这个场景中，我有一张名为cloth的桌子，我有3种颜色的布料，分别是红色、蓝色和绿色。现在的问题是如何使用查询计算每种颜色的比率？

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感谢您的帮助

正如您所说，您有一个名为

cloth

的表，其中包含3种

cloth

和3种

color

。

select cloth, avg(Case when color='red' then 1 else 0 end)/ Count(*) * 1.0 As redratio, avg(Case when color='blue' then 1 else 0 end)/ Count(*) * 1.0 As blueratio, avg(Case when color='green' then 1 else 0 end)/ Count(*) * 1.0 As greenratio
from cloth group by cloth

因此，假设字段名称

cloth

和

color

select cloth, avg(Case when color='red' then 1 else 0 end)/ Count(*) * 1.0 As redratio, avg(Case when color='blue' then 1 else 0 end)/ Count(*) * 1.0 As blueratio, avg(Case when color='green' then 1 else 0 end)/ Count(*) * 1.0 As greenratio
from cloth group by cloth

请尝试：

select cloth, avg(Case when color='red' then 1 else 0 end)/ Count(*) * 1.0 As redratio, avg(Case when color='blue' then 1 else 0 end)/ Count(*) * 1.0 As blueratio, avg(Case when color='green' then 1 else 0 end)/ Count(*) * 1.0 As greenratio
from cloth group by cloth

 select
 1.0 * sum(color='red')/count(*) as redRatio,
 1.0 * sum(color='green')/count(*) as greenRatio,
 1.0 * sum(color='blue')/count(*) as blueRatio
 from cloth