Question

I am trying to save cascading in EF 4.1 code first.

[Table("User")]
public class User
  {
    [Key]
    public Int64 UserId { get; set; }
    public virtual UserRole UserRole { get; set; }

}

[Table("UserRole")]
public class UserRole
{
    [Key,Column(Order = 0)]
    public int RoleID { get; set; }
    [Key,Column(Order = 1)]
    public Int64 UserId { get; set; }


}

when I am trying to save the user by populating the userrole inside it. it is giving error.

The INSERT statement conflicted with the FOREIGN KEY constraint
“FK_User_UserRole”. The conflict occurred in database “x”, table
“dbo.User”, column ‘UserId’. The statement has been terminated.

using (Database database = new Database())
{                
      database.User.Add(user);
      database.SaveChanges();  //it is giving error here.
}

Any ideas?

Answer 1

You need to configure the shared primary key mapping. Otherwise EF can not order the insert statements properly. In your case a User record has to be inserted first and then insert the UserRole with the generated primary key of User.

[Table("User")]
public class User
  {
    [Key]
    public Int64 UserId { get; set; }

    public virtual UserRole UserRole { get; set; }
}

[Table("UserRole")]
public class UserRole
{
    [Key,Column(Order = 0)]
    public int RoleID { get; set; }

    [Key,Column(Order = 1)]
    public Int64 UserId { get; set; }

    public virtual User User { get; set; }
}

In your OnModelCreating method

modelBuilder.Entity<UserRole>().HasRequired(r => r.User)
   .WithOptional(u => u.UserRole);

Then

var user = new User { UserRole = new UserRole() };

using (Database database = new Database())
{                
      database.User.Add(user);
      database.SaveChanges();
}