实体框架 - 1对1的关系，其中一端是不是主键 [英] Entity Framework - 1 to 1 relationship where one end is not a primary key

问题描述

我想限定在实体框架的数据模型，该模型是1对1的一端为一个表中的主键，另一端上的另一个的外键关系。例如：

 表：aspnet_Users
W /西：用户ID GUID主键
 

与aspnet_Users表格内与用户表的AspUserId列的用户ID属性：

 表：用户
W /西：用户ID int主键
W /西：AspUserId GUID
 

当我尝试这样做，我得到一个错误，指出由于AspUserId字段不是它的一个主键的表，该表将无法工作：

  

错误21错误113：多重不在角色用户的关系FK_User_aspnet_Users有效。因为从属角色属性不是关键性质，上限从属作用的多重性必须*。

解决方案

外键需要映射到主键。否则，下面的记录可能发生：

  aspnet_Users
用户帐号
11111111
11111111
22222222

用户
用户ID AspUserId
1 11111111
2 11111111
 

这没有任何意义 - 而伤了你的1-1基数

不过 - 他这样说（看着一个老成员DB - 呸），用户ID 字段 dbo.aspnet_Users 是的主键。

你确定你有你在正确的表的外键？请问 dbo.aspnet_Users 您的数据库有PK的用户ID 。

此外 - 尽量不要映射成员表 - 这将是一个痛苦的世界。在会员架构的关系的高度复杂的的。

刚刚绘制自己的用户表。它的优良有FK的数据库方面的工作（审计，存储过程，触发器等）。

不过，从模型边 - 你应该通过成员资格提供API通过EF您的用户实体，你aspnet_Users（会员）实体交互

如果您需要在code（通常情况下）缝合在一起，然后封装背后的服务。

I'd like to define a relationship in an Entity Framework data model that is 1-to-1 with one end as a primary key of one table and the other end a foreign key on another. For instance:

table: aspnet_Users
w/ col: UserId guid Primary Key

with the UserId property of the aspnet_Users table related to the AspUserId column of the User table:

table: User
w /col: UserId int Primary Key
w /col: AspUserId guid

When I try to do this I get an error saying that since the AspUserId field is not a primary key of it's table that won't work:

Error 21 Error 113: Multiplicity is not valid in Role 'User' in relationship 'FK_User_aspnet_Users'. Because the Dependent Role properties are not the key properties, the upper bound of the multiplicity of the Dependent Role must be *.

解决方案

Foreign keys need to map to primary keys. Otherwise, the below records could happen:

aspnet_Users
UserId 
11111111
11111111
22222222

User
UserId AspUserId
1      11111111
2      11111111

And that doesn't make sense - and breaks your 1-1 cardinality.

However - that being said (looking at an old membership db - yuck), UserId field on dbo.aspnet_Users is a primary key.

Are you sure you have your foreign key on the correct table? Does dbo.aspnet_Users on your database have the PK for UserId.

Also - try not to map the membership tables - it will be a world of pain. The relationships in the membership schema are highly complicated.

Just map your own User table. It's fine to have the FK for database-side work (auditing, stored procedures, triggers, etc).

But from the model side - you should be interacting with your User entity via EF, and your aspnet_Users (Membership) entity via the Membership Provider API.

If you need to "stitch them together" in your code (often the case), then encapsulate that behind a service.

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