Question

I’m trying to map the following entity and the problem is that EF makes CloseUserID as required even when they are not annotated with Required attribute.

 public class UserRegistration {
    [Key]
    public string RegistrationID { get; set; }

    [Required]
    public DateTime CreatedAt { get; set; }

    public Nullable<DateTime> ClosedAt { get; set; }

    [Required]
    public int UserID { get; set; }

    [Required]
    [ForeignKey("UserID")]
    public virtual User User { get; set; }

    public int CloseUserID { get; set; }

    [ForeignKey("CloseUserID")]
    public virtual User CloseUser { get; set; }
  }

How can I make EF understand that CloseUserID is optional and not required?

Answer 1

Put

public int? CloseUserID { get; set; }

This is it. You don’t need to put that FK annotation above the navigation property.