小编Dee*_*kha的帖子

我有两个表User,并UserRoles在SQL Server中.Usertable有基本的用户信息,例如UserId,Nameetc,并且UserRoles有像这样的列UserId,RoleName.这两个表之间存在一对多的关系,即一个用户可以拥有多个角色.

用户

UserId  Name
1       A
2       B
3       C

的UserRole

UserId  Rolename
1       Manager
1       Event Organiser
2       Supervisor
2       Employee
2       Some otherRole

我需要在sql中编写一个查询,它将返回如下.即将一个到多个记录连接成一个字符串

UserId  Roles
1       Manager,Event Organiser
2       Supervisor,Employee,Some otherRole

select table1.t1 from
(
(
select   
         ItemCategory.Name as Category,
         InventoryItems.Name as ItemName,
         sum(SalesItems.Quantity) as Quantity,
         (InventoryItems.Weight*sum(SalesItems.Quantity)) as Weight,
         sum(SalesItems.Amount) as Amount
   from SalesInvoices 
   inner join Sales on Sales.ID = SalesInvoices.SalesID 
   inner join SalesItems on SalesItems.SalesID = Sales.ID
   inner join InventoryItems on InventoryItems.ID = SalesItems.InventoryItemID 
   inner join ItemCategory on ItemCategory.ID = InventoryItems.ItemCategoryID 
   inner join BusinessPartners on Sales.BusinessPartnerID = BusinessPartners.ID
   where SalesInvoices.Date >= '2013-07-1' and SalesInvoices.Date <= '2013-11-7'
   group by ItemCategory.Name,InventoryItems.Name,InventoryItems.Weight
) as t1,
(
select  
        ItemCategory.Name as Category,
        InventoryItems.Name as ItemName, …

（我已经查过了，找不到答案，如果这是重复的，只需指出一个链接，我将删除此问题）

假设我有以下代码

select CASE WHEN lower(Http_User_Agent) like '%mobi%' then 'Mobile' 
            else 'Desktop' end as Device
from Http_User_Agent
where Device = 'Mobile'

哪个返回

Msg 207, Level 16, State 1, Line 4
Invalid column name 'Device'.

我基本上要做的是按新创建的 column 进行过滤Device。有没有简单的方法？

我在 Windows 7 上使用 SQL Server 2008