内部联接在同一张桌子上

时间:2019-08-14 14:12:09

标签: sql inner-join

我有2个查询,第一个:

Select Distinct App_Form_Name,Control_Name
From Application_Form_Controls_Management
where Control_Type = 'ASPxGridView'
Order By App_Form_Name, Control_Name

这将返回(例如):

App_Form_Name | Control_Name
Form1         | ControlName1
Form1         | ControlName2 

第二个:

Select Distinct App_Form_Name, Right_ID, App_Form_Function_ID
From Application_Form_Controls_Management
where Control_Type = 'ASPxGridView'
Order By App_Form_Name,Right_ID,App_Form_Function_ID

这将返回(例如):

App_Form_Name | Right_ID | App_Form_Function_ID
Form1         | 1        | 1
Form1         | 1        | 2
Form1         | 1        | 3
Form1         | 2        | 1
Form1         | 2        | 1
Form1         | 2        | 1

我想要的是Inner Join查询,它将返回以下结果:

App_Form_Name | Control_Name | Right_ID | App_Form_Function_ID
Form1         | ControlName1 | 1        | 1
Form1         | ControlName1 | 1        | 2
Form1         | ControlName1 | 1        | 3
Form1         | ControlName1 | 2        | 1
Form1         | ControlName1 | 2        | 2
Form1         | ControlName1 | 2        | 3
Form1         | ControlName2 | 1        | 1
Form1         | ControlName2 | 1        | 2
Form1         | ControlName2 | 1        | 3
Form1         | ControlName2 | 1        | 1
Form1         | ControlName2 | 1        | 2
Form1         | ControlName2 | 1        | 3

谢谢。

1 个答案:

答案 0 :(得分:1)

您需要使用查询作为子查询,如下所示:

Select a.App_Form_Name,a.Control_Name, b.Right_ID, b.App_Form_Function_ID
From
   (
    Select Distinct App_Form_Name,Control_Name From Application_Form_Controls_Management where Control_Type='ASPxGridView' 
   ) a
Inner join (
              Select Distinct App_Form_Name,Right_ID,App_Form_Function_ID From 
              Application_Form_Controls_Management where Control_Type='ASPxGridView'
           ) b
on a.App_Form_Name = b.App_Form_Name

如果您使用的是SQL Server,还可以受益于cte这样的结构:

;with cte as (
   Select Distinct App_Form_Name,Control_Name From 
   Application_Form_Controls_Management where Control_Type='ASPxGridView' 
),
cte2 as (
   Select Distinct App_Form_Name,Right_ID,App_Form_Function_ID From 
                   Application_Form_Controls_Management where Control_Type='ASPxGridView'
)
select cte.App_Form_Name,cte.Control_Name, cte2.Right_ID, cte2.App_Form_Function_ID
from cte
inner join cte2 on cte.App_Form_Name = cte2.App_Form_Name