SQL Server 2005多部分标识符“；x"；无法约束

我想我有语法问题，但我正在努力寻找答案

有人能解释一下原因吗

SELECT TOP 3 * FROM Facilities 
        INNER JOIN FacilityStates 
        ON FacilityStates.Asset = Facilities.ID
        WHERE Facilities.ID = 'MyFacility'

编译并返回合适的结果，但我认为是完全限定的版本

SELECT TOP 3 * FROM [dbo].[Facilities] 
               INNER JOIN [dbo].[FacilityStates]
               ON [dbo].[FacilityStates.Asset] = [dbo].[Facilities.ID]
               WHERE [dbo].[Facilities.ID] = 'MyFacility'

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抛出“无法绑定多部分标识符“x”。对于“on”子句和“where”子句的左、右部分？

，因为您正在将

表组合在一起。列

在一组方括号中：

....
ON [dbo].[FacilityStates.Asset] = [dbo].[Facilities.ID] 
....

SELECT TOP 3 * FROM [dbo].[Facilities]  
               INNER JOIN [dbo].[FacilityStates] 
               ON [dbo].[FacilityStates].[Asset] = [dbo].[Facilities].[ID] 
               WHERE [dbo].[Facilities].[ID] = 'MyFacility' 

这应该是：

....
ON [dbo].[FacilityStates].[Asset] = [dbo].[Facilities].[ID] 
....

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SQL Server中的方括号用于显式表示可能包含空格或保留字的对象名称。因此，当您在一组括号内组合

FacilityStates.Asset

时，您告诉SQL Server有一个具有该名称的对象。没有。这是方括号的位置：

....
ON [dbo].[FacilityStates.Asset] = [dbo].[Facilities.ID] 
....

SELECT TOP 3 * FROM [dbo].[Facilities]  
               INNER JOIN [dbo].[FacilityStates] 
               ON [dbo].[FacilityStates].[Asset] = [dbo].[Facilities].[ID] 
               WHERE [dbo].[Facilities].[ID] = 'MyFacility' 

---

试着找出方括号内的所有内容都是一个名称。您使用方括号将表名和字段名框在一起。有效查询是：

SELECT TOP 3 * 
FROM [dbo].[Facilities] 
INNER JOIN [dbo].[FacilityStates]
  ON [dbo].[FacilityStates].[Asset] = [dbo].[Facilities].[ID]
WHERE [dbo].[Facilities].[ID] = 'MyFacility'