自我引用多对多关系EF代码 [英] Self-referencing many-to-many relationship EF code first

问题描述

假设我有以下类：

  public class Person 
 {
 public int Id {get;组; } 
 public string Firstname {get;组; } 
 public string Lastname {get;组; } 
 public virtual List< Person>新新旗新新新新新新新新新新新新新新新新新新新新新组; 
} 
  

使用以下EF Fluent API：

  modelBuilder.Entity< Person>（）
 .HasMany（m => m.Friends）
 .WithMany（）
 .Map（m => m.ToTable（Friends））; 
  

数据库生成成功。

问题是当我执行一个que

---

ry with Breeze（客户端）没有数据为朋友属性。

  var query = entityQuery.from （'Person'）
 .where（'id'，'=='，123）
 .expand（好友）; 
  

当执行查询时，我得到所有People实体的所有数据，除了Friends属性总是一个空数组。当我检查Json答案时，我看到数据也被传输。甚至是Friend属性的数据。但是他们没有链接到好友属性本身。

我的问题：

谢谢。

解决方案

你必须声明一个外键人。微风要求FK正确地解决关联。

编辑：

意识到你在询问多对多的关系。 （是的，我应该看过帖子标题...）
微风不支持多对多关联。
但是，您可以拥有两个一对多的关系，作为一对多的关系。 （即多对一）在这种情况下，您将需要如前所述定义链接表/实体和外键。 （请参阅 http://www.breezejs.com/documentation/navigation-properties ）

I work with ASP.NET MVC With Durandal/Breeze templates.

Let's say I have the following class:

public class Person
{
    public int Id { get; set; }
    public string Firstname { get; set; }    
    public string Lastname { get; set; }
    public virtual List<Person> Friends { get; set; }
}

With the following EF Fluent API:

modelBuilder.Entity<Person>()
            .HasMany(m => m.Friends)
            .WithMany()
            .Map(m => m.ToTable("Friends"));

The database is generated successfully.

The problem is when I perform a que

---

ry with Breeze (client side) I have no data for the Friends property.

    var query = entityQuery.from('Person')
        .where('id', '==', 123)
        .expand("Friends");

When the query is executed I get as result the requested People entity with all the data except the Friends property is always an empty array. When I check the Json answer I see that also the data are transmitted. Even data for the Friends property. However they are not linked to the Friends property itself.

My question: what do I have to do to have my Friends property filled with values?

Thanks.

解决方案

You must declare a foreign key in Person. Breeze requires the FK to correctly resolve associations.

Edit:

I just realized you are asking about a many-to-many relationship. (yeah, I should have read the post title...) Breeze does not support many-to-many associations. However, you could have two one-to-many relationships to work as a many-to-many. (i.e. many-to-one-to-many) In this case, you will need to define the linking table/entity and the foreign key as mentioned earlier. (see http://www.breezejs.com/documentation/navigation-properties)

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