sql - 计数 SQL 的百分比

Question

你怎么能得到一个计数的百分比？尝试根据行数计算百分比时，我得到了所有相同的值。我想要每个属性的百分比取决于有多少 COUNT。因此，如果我计算一个属性 30 次，我希望它根据行数和其他值更改为百分比。

SELECT  Attribute
      , COUNT(Attribute) / COUNT(*) * 100 AS TopIssues
FROM    Audits 
        WHERE MONTH(TransActionDate) = MONTH(GETDATE())
GROUP BY Attribute
ORDER BY COUNT(Attribute) DESC     

Answer 1

在 SQL Server 中，您可以使用：

SELECT  Attribute
      , COUNT(Attribute)*1.0 / SUM(COUNT(*)) OVER() * 100 AS TopIssues
FROM    Audits 
WHERE MONTH(TransActionDate) = MONTH(GETDATE())
GROUP BY Attribute
ORDER BY COUNT(Attribute) DESC   

Answer 2

你也可以这样做：

SELECT  Attribute
      , COUNT(Attribute)*1.0 / ACount AS TopIssues
FROM    Audits 
CROSS JOIN (SELECT COUNT(1) ACount FROM Audits) ACount
WHERE MONTH(TransActionDate) = MONTH(GETDATE())
GROUP BY Attribute, ACount
ORDER BY COUNT(Attribute) DESC