sql-server - SQL Server 错误 : maximum number of prefixes. 最大为 3. with join 语法

Question

尝试运行跨服务器更新:

UPDATE ASILIVE.CustomerManagementSystem.dbo.Sessions
SET ASILIVE.CustomerManagementSystem.dbo.Sessions.VarianceAmount=Variances.VarianceAmount
FROM ASILIVE.CustomerManagementSystem.dbo.Sessions
    INNER JOIN Variances
    ON ASILIVE.CustomerManagementSystem.dbo.Sessions.SessionGUID = Variances.SessionGUID
WHERE ASILIVE.CustomerManagementSystem.dbo.Sessions.VarianceAmount <> Variances.VarianceAmount

给出错误:

Msg 117, Level 15, State 2, Line 5
The number name 'ASILIVE.CustomerManagementSystem.dbo.Sessions' contains 
more than the maximum number of prefixes. The maximum is 3.

是什么赋予了？

也可以看看

SQL Server Error: "maximum number of prefixes. The maximum is 3" with subselect syntax
(处理子选择语法；这个问题涉及连接语法)

不重要的研究:

我尝试将事物随机别名为 s :

UPDATE ASILIVE.CustomerManagementSystem.dbo.Sessions s
SET s.VarianceAmount=Variances.VarianceAmount
FROM ASILIVE.CustomerManagementSystem.dbo.Sessions s
    INNER JOIN Variances
    ON s.SessionGUID = Variances.SessionGUID
WHERE s.VarianceAmount <> Variances.VarianceAmount

但这不起作用:

Msg 117, Level 15, State 2, Line 5
The number name 'ASILIVE.CustomerManagementSystem.dbo.Sessions' contains 
more than the maximum number of prefixes. The maximum is 3.

Hamlin 建议添加括号:

UPDATE [ASILIVE].[CustomerManagementSystem].dbo.Sessions
SET [ASILIVE].[CustomerManagementSystem].dbo.Sessions.DisciplineVarianceAmount=DisciplineVariances.VarianceAmount
FROM [ASILIVE].[CustomerManagementSystem].dbo.Sessions
    INNER JOIN DisciplineVariances
    ON [ASILIVE].[CustomerManagementSystem].dbo.Sessions.SessionGUID = DisciplineVariances.SessionGUID
WHERE [ASILIVE].[CustomerManagementSystem].dbo.Sessions.DisciplineVarianceAmount <> DisciplineVariances.VarianceAmount

但这不起作用:

Msg 117, Level 15, State 2, Line 5
The number name 'ASILIVE.CustomerManagementSystem.dbo.Sessions' contains
more than the maximum number of prefixes. The maximum is 3.

Answer 1

你真的喜欢打很多字吗？ :-)

UPDATE s
  SET s.DisciplineVarianceAmount = v.VarianceAmount
  FROM [ASILIVE].[CustomerManagementSystem].dbo.Sessions AS s
  INNER JOIN dbo.Variances AS v
  ON s.SessionGUID = v.SessionGUID
  AND s.VarianceAmount <> v.VarianceAmount;

请注意，如果任一方差数量当前为 NULL ，您可能想在此处描述要执行的操作。