Not sure how to get around 'Unable to determine the principal end of an association' error

Question

There are a lot of threads on this error, and I've read a ~half dozen of them. (Some of which didn't apply because the relationship wasn't 1:1.) I've tried a few things, but I am still getting the error.

I have two tables, Account and AccountSettings. They have a 1:1 relationship. However, Account is the primary. It can exist w/o AccountSettings, but not the other way around.

This is what I had originally...

public class Account
{
    [Key]
    public int AccountID { get; set; }
    public int? AccountSettingID { get; set; }

    [ForeignKey("AccountSettingID ")]
    public virtual AccountSetting AccountSetting { get; set; }
}

And then...

public class AccountSetting 
{
    [Key]
    public int AccountSettingID { get; set; }
    public int AccountID { get; set; }

    [ForeignKey("AccountID ")]
    public virtual Account Account { get; set; }
}

But that got me the error:

Unable to determine the principal end of an association between the types 'EZHomes.Data.Model.AccountSetting' and 'EZHomes.Data.Model.Account'. The principal end of this association must be explicitly configured using either the relationship fluent API or data annotations.

How do I specify Account as the principle?

Thanks!

Answer 1

I finally figured it out. Hopefully this will help somebody else. In the non-primary table:

public class AccountSetting 
{
    [Key]
    public int AccountSettingID { get; set; }
    [Required]
    public int AccountID { get; set; }

    [Required, ForeignKey("AccountID ")]
    public virtual Account Account { get; set; }
}