sql - IDENTITY INSERT 不适用于 MERGE

Question

我有以下代码:

PRINT N'Merging Wide Format Types...'
SET IDENTITY_INSERT WideFormatTypes ON
GO
MERGE INTO WideFormatTypes AS Target
USING (VALUES 
    (1, N'****', NULL),
    (2, N'****', NULL),
    (3, N'******', NULL),
    (4, N'*******', NULL),
    (5, N'******', NULL),
    (6, N'*******', NULL)
)
AS Source (TypeID, TypeName, Description) 
ON Target.TypeID = Source.TypeID
WHEN MATCHED THEN
    UPDATE SET
    TypeID = Source.TypeID,
    TypeName = Source.TypeName,
    Description = Source.Description
WHEN NOT MATCHED BY TARGET THEN 
    INSERT (TypeID, TypeName, Description) 
    VALUES (TypeID, TypeName, Description);

SET IDENTITY_INSERT WideFormatTypes OFF
GO

它返回一个错误

Msg 8102, Level 16, State 1, Line 1
Cannot update identity column 'TypeID'

该表声明如下:

CREATE TABLE [dbo].[WideFormatTypes] 
(
    [TypeID]      INT             IDENTITY (1, 1) NOT NULL,
    [TypeName]    NVARCHAR (500)  NOT NULL,
    [Description] NVARCHAR (1000) NULL,
    PRIMARY KEY CLUSTERED ([TypeID] ASC)
);

我找不到问题..有什么帮助吗？

Answer 1

尝试从 MERGE 的 UPDATE 部分删除标识列。

IDENTITY_INSERT 是，正如它所说的，用于插入，而不是更新。此外，您在 JOIN 中包含该字段，因此 UPDATE 无论如何都不会实际更改该值。