Uninstall order is unpredictable in Entity Framework

Question

I have the following uninstall method in an Entity Framework Code First project:

var selectedID = selectedGroup.ID;
var users = (from user in db.Users
               where user.Group_ID == selectedID
               select user);
db.Users.RemoveRange(users);

db.Groups.Attach(selectedGroup);
db.Groups.Remove(selectedGroup);
db.SaveChanges();

These are the models:

 public class Group
  {
    [Key]
    public Guid ID { get; set; }

    [Required]
    public Guid Branch { get; set; }

  }

  public class User
  {
    [Key]
    public Guid ID { get; set; }

    [Required]
    public Guid Group_ID { get; set; }

  }

When called db.SaveChanges(), I get an exception:

The DELETE operation is contrary to the REFERENCE clause of "FK_Users_Groups". The conflict occurred in the database "UserDB", the table "dbo.Users", the column "Group_ID". Application completed.

It seems that the Remove methods are called in reverse (random) order. If I add more db.SaveChanges()after RemoveRange(), it (obviously) works fine.

How can I force delete an order?

Answer 1

EF . DML . . , .

. , . .