Asp.net 如何在sql中计算平均整数值

我有一些问题需要解决程序中的一个错误。我试图平均一个整数列，但当平均值为0时出现错误。有些东西，，， 例如，我有一个数据：

Varchar1  |  Varchar2 | Value
1401_1   | 1401_1_1  | 1
1401_1   | 1401_1_2  | 0
1401_1   | 1401_1_3  | 1
1401_1   | 1401_1_4  | 1
1401_1   | 1401_1_5  | 0

然后我用group by varchar1对值求和，结果得到0，它应该是0,6。这是我的密码：

        Dim sqlProducts As String = "SELECT * FROM (SELECT TOP 7 [Varchar1] AS Varchar1_, AVG(CASE WHEN [Type] = 'Something1' THEN Value1 ELSE 0 END) AS Display1, AVG(CASE WHEN [Type] = 'Something2' THEN Value1 ELSE 0 END) AS [Display2] FROM tbl_table GROUP BY [Varchar1] order by [Varchar1] DESC)x ORDER BY Varchar1_ ASC"

我认为我不能从整数中得到十进制的结果，然后我希望它在0.0时显示1，所以它取上限值。有可能怎么做吗

谢谢你的帮助。非常感谢。

您的问题是：

SELECT *
FROM (SELECT TOP 7 [Varchar1] AS Varchar1_, AVG(CASE WHEN [Type] = 'Something1' THEN Value1 ELSE 0 END) AS Display1, AVG(CASE WHEN [Type] = 'Something2' THEN Value1 ELSE 0 END) AS [Display2]
      FROM tbl_table
      GROUP BY [Varchar1]
      order by [Varchar1] DESC
     )x
ORDER BY Varchar1_ ASC

SQL Server进行整数除法，这也适用于

AVG（）

。使用浮点数

SELECT *
FROM (SELECT TOP 7 [Varchar1] AS Varchar1_,
             AVG(CASE WHEN [Type] = 'Something1' THEN cast(Value1 as float) ELSE 0 END) AS Display1,
             AVG(CASE WHEN [Type] = 'Something2' THEN cast(Value1 as float) ELSE 0 END) AS [Display2]
      FROM tbl_table
      GROUP BY [Varchar1]
      order by [Varchar1] DESC
     ) x
ORDER BY Varchar1_ ASC

顺便说一下，我发现

else 0

可疑。这将用

0

替换不匹配的值。更典型的情况是，您希望忽略它们：

SELECT *
FROM (SELECT TOP 7 [Varchar1] AS Varchar1_,
             AVG(CASE WHEN [Type] = 'Something1' THEN cast(Value1 as float) END) AS Display1,
             AVG(CASE WHEN [Type] = 'Something2' THEN cast(Value1 as float) END) AS [Display2]
      FROM tbl_table
      GROUP BY [Varchar1]
      order by [Varchar1] DESC
     ) x
ORDER BY Varchar1_ ASC