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Does Entity Framework remove valid content without permission in a non-deterministic way?

I am having problems storing data in a database using EF. Normally, all CRUD operations work fine for the rest of the program, but I recently noticed that in the case of the m: n relationship, the hard part arises.

I am using EF4.1 with the first code approach. The interesting parts of my classes are as follows:

public class Publication : IItem, IDataErrorInfo {

     ...

    [InverseProperty("Publications")]
    public virtual ICollection<Group> Groups{ get; set; }
}

public class Group : IItem, IDataErrorInfo {

     ...

    [InverseProperty("Groups")]
    public virtual ICollection<Publication> Groups{ get; set; }
}

The database is created as follows:

    public PublicationsDB() : base("PublicationDB") {
        this.Configuration.AutoDetectChangesEnabled = true;
    }

    public DbSet<Publication> Publications { get; set; }
    public DbSet<Software> Softwares { get; set; }
    public DbSet<Group> Group{ get; set; }

The goal is to create an m: n relationship between publications and groups.

XML, . , ICollection, SaveChanges(). ( ), ICollection.

:

:

  • , ICollection<Group>, xml
  • . ICollection<Publication> null.

? . , : DBSet<Groups> . , A B, A.ICollection = null and B.ICollection.Count =1 (which is by the way wrong), , .. A.ICollection = null and B.ICollection = null (which is also wrong)

?

? ? ?:)

, . Publication (m):(n) Group - Publication (m):(1) NewEntityRelation (n):1 Group, , .

.

+3
1

, InverseProperty EF- , EF , . , , "m: n", , " ", , EF . " ", OnModelCreating. :

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Entity<User>()
            .HasMany(a => a.Roles)
            .WithMany(r => r.Users)
            .Map(config =>
            {
                config.ToTable("UserRoles");
                config.MapLeftKey("UserId");
                config.MapRightKey("RoleId");
            });
    }

, " " . , EF "" , , , . , , , EF , .

+3

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