如何在.net核心中打开身份插入 [英] How to turn on identity-insert in .net core

问题描述

我在EF中创建了一些表，并输入了一些种子数据，在其中使用主键为几列赋值。当我运行应用程序时，我收到错误消息：

I made a few tables in EF and entered in some seed data where I give value to a few columns with a primary key. When I run the application I am getting the error message:

当IDENTITY_INSERT设置为OFF时，无法为表'Persons'中的Identity列插入显式值。

Cannot insert explicit value for identity column in table 'Persons' when IDENTITY_INSERT is set to OFF.

如何打开它？我在这里阅读使用：

How do I turn it on? I read on here to use:

[DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]

在作为主键的属性上方。不幸的是，我仍然收到相同的错误消息。请帮忙。

above the property that is a primary key. I am still getting the same error message unfortunately. Please help.

我向所有具有主键的属性添加了 [DatabaseGenerated（DatabaseGeneratedOption.None）] 。当我运行迁移时，我可以看到标识列已删除，但是我仍然收到相同的错误消息。

I added [DatabaseGenerated(DatabaseGeneratedOption.None)] to all my properties that have a primary key. When I ran the migration I can see that the identity column is removed, But I am still getting the same error message.

当我进入SQL SEO时，仍可以在主键上看到标识列。我尝试刷新数据库。我究竟做错了什么？我唯一能做的就是进入属性并删除身份，但是为什么我不能按照上面提到的方式做呢？

When I go into SQL SEO I can still see the identity column on my primary key. I tried refreshing the database. What am I doing wrong? The only thing I can do is go into properties and remove the identity, but why can't I do it the way mentioned above?

推荐答案

在EF Core 1.1.2中，我将其用于事务处理。在我的数据库初始化程序中，将种子数据放入表中。我使用了此EF6答案中的技术。以下是代码示例：

In EF Core 1.1.2, I got this to work with transactions. In my "database initializer" that put seed data into the tables. I used the technique from this EF6 answer. Here's a sample of the code:

using (var db = new AppDbContext())
using (var transaction = db.Database.BeginTransaction())
{
    var user = new User {Id = 123, Name = "Joe"};
    db.Users.Add(user);
    db.Database.ExecuteSqlCommand("SET IDENTITY_INSERT MyDB.Users ON;");
    db.SaveChanges();
    db.Database.ExecuteSqlCommand("SET IDENTITY_INSERT MyDB.Users OFF");
    transaction.Commit();
}

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