Question

好友

我有一个MSSQL查询。就是这样......

SELECT DISTINCT resource.locationurl, 
                resource.resourcename, 
                resource.anwserid, 
                checktotal.total 
FROM   resource 
       INNER JOIN (SELECT Count(DISTINCT anwserid) AS total, 
                          resourcename 
                   FROM   resource AS Resource_1 
                   WHERE  ( anwserid IN (SELECT Cast(value AS INT) AS Expr1 
                                         FROM   dbo.Udf_split(@sCategoryID, ',') 
                                                AS 
                                                udf_Split_1) ) 
                   GROUP  BY resourcename) AS checktotal 
               ON resource.resourcename = checktotal.resourcename 
WHERE  ( resource.anwserid IN (SELECT Cast(value AS INT) AS Expr1 
                               FROM   dbo.Udf_split(@sCategoryID, ',') AS 
                                      udf_Split_1) 
       ) 
       AND ( checktotal.total = @Total ) 
ORDER  BY resource.resourcename

我运行此查询但它给了我重复的Resource.LocationURL列。

您可以直接查看http://www.ite.org/visionzero/toolbox/default2.aspx

检查上面的链接，你可以在哪里开火选择一些类别，但结果并不明显..

我尝试了大部分时间，但现在我不在乎请帮助我。

Answer 1

您误解了DISTINCT在获取多个列时的含义。

如果您运行此查询：

SELECT DISTINCT col1, col2 FROM table

您选择了每个不同的组合。可接受的结果是

value 1_1, value 2_1
value 1_1, value 2_2,
value 2_1, value_2_1

在此示例中，value 1_1出现两次，但两列合并是唯一的。

我的猜测是你实际上是在尝试进行分组：

SELECT resource.locationurl, 
       resource.resourcename, 
       resource.anwserid, 
       Sum(checktotal.total) 
FROM   resource 
       INNER JOIN (SELECT Count(DISTINCT anwserid) AS total, 
                          resourcename 
                   FROM   resource AS Resource_1 
                   WHERE  ( anwserid IN (SELECT Cast(value AS INT) AS Expr1 
                                         FROM   dbo.Udf_split(@sCategoryID, ',') 
                                                AS 
                                                udf_Split_1) ) 
                   GROUP  BY resourcename) AS checktotal 
               ON resource.resourcename = checktotal.resourcename 
WHERE  ( resource.anwserid IN (SELECT Cast(value AS INT) AS Expr1 
                               FROM   dbo.Udf_split(@sCategoryID, ',') AS 
                                      udf_Split_1) 
       ) 
       AND ( checktotal.total = @Total ) 
GROUP  BY resource.locationurl, 
          resource.resourcename, 
          resource.anwserid

Answer 2

首先，您关联的网站没有做任何事情。

其次，DISTINCT确保唯一的行。它不会使所有列中的值都是唯一的。考虑一下！它会如何工作？您有两行具有相同的locationurl字段，但具有其他不同元素。你不包括哪一个？

最后，请更加谨慎地处理您的问题。

Answer 3

因为我看到您的查询是在多列上选择DISTINCT，所以如果任何记录至少有一个col的差异，那么它就会传递DISTINCT条件

例如：

record1 : locationurl |  resourcename | anwserid  | Sum(checktotal.total)
             loc1         res1          1                100
record2 : locationurl |  resourcename | anwserid  | Sum(checktotal.total)
             loc1         res1          2                100

DISTINCT查询没有工作，它给我输出

3 个答案: