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为什么SCOPE_IDENTITY()在表中插入一行后返回NULL ComponentAssociation（@@IDENTITY返回正确的Id），而SCOPE_IDENTITY()在表中插入一行后返回正确的Id CustomerProjectAssociation？

两个关联表的创建方式相同。

这是表创建脚本的摘录：

-- Creating table 'CustomerProjectAssociation'
CREATE TABLE [dbo].[CustomerProjectAssociation] 
(
    [Id] int IDENTITY(1,1) NOT NULL,
    [CustomerId] int  NOT NULL,
    [ProjectId] int  NOT NULL,
    [CreationDate] datetime NOT NULL CONSTRAINT DF_CustomerProjectAssociation_CreationDate DEFAULT (SYSUTCDATETIME()),
    [LastModificationDate] datetime NOT NULL CONSTRAINT DF_CustomerProjectAssociation_ModificationDate DEFAULT (SYSUTCDATETIME())
);
GO

-- Creating table 'ComponentAssociation'
CREATE TABLE [dbo].[ComponentAssociation] 
(
    [Id] int IDENTITY(1,1) NOT NULL,
    [EcuId] int  NOT NULL,
    [CreationDate] datetime NOT NULL CONSTRAINT DF_ComponentAssociation_CreationDate DEFAULT (SYSUTCDATETIME()),
    [LastModificationDate] datetime NOT NULL CONSTRAINT DF_ComponentAssociation_ModificationDate DEFAULT (SYSUTCDATETIME()),
    [ComponentId] int  NOT NULL
);
GO

-- Creating primary key on [Id] in table 'CustomerProjectAssociation'
ALTER TABLE [dbo].[CustomerProjectAssociation]
      ADD CONSTRAINT [PK_CustomerProjectAssociation]
          PRIMARY KEY CLUSTERED ([Id] ASC);
GO

-- Creating primary key on [Id] in table 'ComponentAssociation'
ALTER TABLE [dbo].[ComponentAssociation]
      ADD CONSTRAINT [PK_ComponentAssociation]
          PRIMARY KEY CLUSTERED ([Id] ASC);
GO

下面是从 SQL Server Management Studio 对数据库执行的两个查询：

INSERT [dbo].[CustomerProjectAssociation]([CustomerId], [ProjectId])
VALUES (1, 2)

SELECT 
    [RowCount] = @@RowCount,
    [@@IDENTITY] = @@IDENTITY,
    [SCOPE_IDENTITY] = SCOPE_IDENTITY()

结果：

    RowCount @@IDENTITY SCOPE_IDENTITY
        1         24          24

INSERT [dbo].[ComponentAssociation]([EcuId], [ComponentId])
VALUES(1, 2)

SELECT 
    [RowCount] = @@RowCount,
    [@@IDENTITY] = @@IDENTITY,
    [SCOPE_IDENTITY] = SCOPE_IDENTITY()

结果：

    RowCount @@IDENTITY SCOPE_IDENTITY
        1        613        NULL
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1 回答 1

0

好的，问题解决了。

在此处找到解决方案：插入表时出错，而不是从实体数据框架触发

我在返回所有计算列的而不是插入更新触发器的末尾添加了以下选择语句：

select [Id], [CreationDate], [LastModificationDate] from {0}.[dbo].[ComponentAssociation] where @@ROWCOUNT > 0 and Id = scope_identity()
于 2016-07-14T08:01:21.393 回答