Entity framework - table per type issue

Question

I'm having troubles using Entity Framework with table-per-type inheritance. The result I get is one extra column in the ' PostComments ' table.

Here's my code so far:

BaseComment class:

   public abstract class BaseComment
   {
        [Key]
        public int Id { get; set; }

        [Required]
        [AllowHtml]
        public string Content { get; set; }

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

        public int? ParentId { get; set; }

        public int UserId { get; set; }

        [Required]
        public CommentStatus CommentStatus { get; set; }

        [ForeignKey("ParentId")]
        public virtual BaseComment Parent { get; set; }

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

PostComment class

public class PostComment : BaseComment
{
    public int PostId { get; set; }

    [ForeignKey("PostId")]
    public virtual Post Post { get; set; }
}

PageComment class

public class PageComment : BaseComment
{
    public int PageId { get; set; }

    [ForeignKey("PageId")]
    public virtual Page Page { get; set; }
}

---

My Seed() method

protected override void Seed(DAL.Contexts.XPressDbContext context)
{
    context.PostComments.AddOrUpdate(new PostComment()
    {
        Content = "asdasd",
        PostId = 1,
        TimeCreated = DateTime.Now,
        UserId = 1,
        CommentStatus = CommentStatus.Approved
    });

    context.PageComments.AddOrUpdate(new PageComment()
    {
        Content = "About page comment",
        PageId = 17,
        TimeCreated = DateTime.Now,
        UserId = 1,
        CommentStatus = CommentStatus.Approved
    });
}

SQL result: See a Page_Id column in PostComments table. That column should not be present there.

Can anyone tell me where I'm wrong? Any help is appreciated!

Answer 1

Your TPT definition is correct. This extra column that you see does not seem to be an issue with your TPT configuration. It looks like the Page class has a reference to PostComments which is creating this extra column.