Question

我在健康俱乐部的SQL Server数据库中有一个客户列表。列出的客户包括他们加入的日期和他们续订的次数我希望能够计算续订客户的百分比率。有关如何做到这一点的任何想法？感谢。

Answer 1

如果某个表subscriptions每个用户只有一行，则会使用isrenewed位进行更新：

 SELECT 
    SUM(SIGN(isrenewed)) * 100 / COUNT(*) 
    AS Percentage
    FROM subscriptions

输出

 Percentage
 ---------------
 66,666666

如果要对表达式进行舍入，可以将其转换为int

 SELECT 
    CAST(
      SUM(SIGN(isrenewed)) * 100 / COUNT(*) 
      AS int)
    AS Percentage
    FROM subscriptions

输出

 Percentage
 ---------------
 66

如果您的表subscriptions具有特定于用户的列userid，其中有两行意味着订阅已续订：

SELECT 
  (SELECT TOP 1 COUNT(*) OVER() 
    FROM subscriptions
    GROUP BY userid
    having COUNT(*) > 1) 
  * 100 / COUNT(*) AS Percentage
  FROM subscriptions

Answer 2

这就是你要找的东西

Declare @t table(Id Int Identity,CustomerName Varchar(50),DOJ Datetime,IsRenewed bit)
Insert Into @t Values('Name1','1/1/2012',1),('Name2','10/1/2012',1),('Name3','10/2/2012',0)

Select PercentageCustomerRenewed = 
Cast((Count(*) * 100) / (Select Count(*) From @t ) AS Numeric(10,2))  
From @t 
where IsRenewed = 1

<强>结果

PercentageCustomerRenewed
66.00

TSQL计算百分比

2 个答案: