title: Entity Framework Guid Id and foreign key record not inserted
body: <pre><code>public partial class Authors
  {
      [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
      public Guid Id { get; set; }
      public string Name { get; set; }        
      protected ICollection&lt;Books&gt; Books { get; set; }
  }
  </code></pre>
  
  <p><code>Authors</code> table has a <code>Guid</code> primary key and I signed it attribute to generate database.</p>
  
  <pre><code>public class Books
  {
      public int Id { get; set; }
      public string Name { get; set; }
      public string ISBNNumber { get; set; }
      public Guid AuthorId { get; set; }
  
      public virtual Authors Author { get; set; }
  }
  
  class Program
  {
      static void Main(string[] args)
      {
          BookStoreEntities1 context = new BookStoreEntities1();
  
          Authors author = new Authors();
          author.Name = "Sample Author Name";
  
          Books authorBook1 = new Books();
          authorBook1.ISBNNumber = "11145-8854-9987";
          authorBook1.Name = "Book 1";
  
          Books authorBook2 = new Books();
          authorBook2.ISBNNumber = "4145-8854-2987";
          authorBook2.Name = "Book 2";
  
          author.AddBook(authorBook1);
          author.AddBook(authorBook2);
  
          context.Authors.Add(author);
          context.SaveChanges();
      }
  }
  </code></pre>
  
  <p>And I created client code to insert a new record into the database. This client code is inserting author to <code>Authors</code> table, but not inserting <code>Books</code>.</p>
  
  <p>If I change <code>Author Id</code> as <code>int</code> (not <code>Guid</code>), in this case <code>Author</code> and <code>Books</code> are inserted in database.</p>
  
  <p>What do you think about this?</p>