Question

我正在尝试一个简单的（或不是）查询来获取存在于2个部门中的用户。

STRUCT：

用户 ID 名称

UserDepartment ID ID用户 IDDepartment

系 ID 名称

所以我想要来自DepartmentA和DepartmentB的用户（

不可能这样做：

Select * from User as US
left join UserDepartment as DP on User.ID = UserDepartment.IDUser
where DP.IDDepartment = 1 and DP.IDDepartment = 2

零结果......

解决此问题的查询类似于：

select * from UserDepartment
where IDDepartment in (1,2)
group by IDUser
having COUNT(*)=2

但这是唯一的解决方案吗？还有其他简单的疑问吗？

Answer 1

获取属于1和2部门的所有用户：

SELECT * 
FROM User
WHERE User.ID IN (SELECT UserID FROM UserDepartment WHERE IDDepartment = 1)
    AND User.ID IN (SELECT UserID FROM UserDepartment WHERE IDDepartment = 2)

结果与后面的查询基本相同，只是它专门查找同时位于＆＃34; 1＆＃34;和＆＃34; 2＆＃34;，而不是任何有2个或更多部门记录属于＆＃34; 1＆＃34;或＆＃34; 2＆＃34; （不包括有两个＆＃34; 1＆＃34;记录但没有＆＃34; 2＆＃34;记录的人。

如果您希望在结果中包含来自userdepartment表的信息，只需将其更改为：

SELECT * 
FROM User US
INNER JOIN (SELECT * FROM UserDepartment WHERE IDDepartment IN(1,2)) DP ON US.ID = DP.UserID
WHERE User.ID IN (SELECT UserID FROM UserDepartment WHERE IDDepartment = 1)
    AND User.ID IN (SELECT UserID FROM UserDepartment WHERE IDDepartment = 2)

Answer 2

这似乎是 INTERSECT 的工作。您可以通过以下操作获取所需的用户ID列表：

SELECT IDUser FROM UserDepartment WHERE IDDepartment = 1

INTERSECT

SELECT IDUser FROM UserDepartment WHERE IDDepartment = 2

Answer 3

                /*** If only users for dept 1 and 2 need to be shown the use this query ****/
                Select * from #User u 
                inner join 
                (

                Select d1.UserID from #UserDepartment d1  
                where d1.Department = 1 
                intersect 
                Select d2.UserID from #UserDepartment d2
                where d2.Department = 2
                except 
                Select d2.UserID from #UserDepartment d2
                where d2.Department not in (1,2)
                )t on u.ID = t.UserID
             /***If the users that belong to dept 1 and 2 and can exist in 
                other depts then use this one**/
             Select * from #User u 
            inner join 
            (

            Select d1.UserID from #UserDepartment d1  
            where d1.Department = 1 
           intersect 
           Select d2.UserID from #UserDepartment d2
          where d2.Department = 2

              )t on u.ID = t.UserID


              /**To test use the following commented code**/
                /*Select * into #User from
                (
                Select 1 as ID, 'A' as Name
                union
                Select 2,'B'
                union
                Select 3,'C'
                union
                Select 4,'D'
                union
                Select 5,'E'
                union
                Select 6,'F'
                union
                Select 7,'G'
                union
                Select 8,'H'
                union
                Select 9,'I'
                union
                Select 10,'G'

                )t


                Select * into #Department from
                (
                Select 1 as ID, 'D1' as Name
                union
                Select 2,'D2'
                union
                Select 3,'D3'
                union
                Select 4,'D4'
                )t2


                Select * into #UserDepartment from 
                (
                Select 1 AS ID ,1 AS UserID ,1 AS Department
                union
                Select 2,1,2
                union 
                Select 3,1,3
                union
                Select 4,2,1
                union
                Select 5,3,2
                union
                Select 6,4,1
                union
                Select 7,4,2


                )t3
               */

有多个Ands的多对多

3 个答案: