asp.net-mvc-3 – 如何使用EF-Code-First将大表分成多个离散类型

我在这里遵循这个例子：http://weblogs.asp.net/manavi/archive/2011/04/24/associations-in-ef-4-1-code-first-part-4-table-splitting.aspx?CommentPosted=true#commentmessage

它适用于主类型和子类型,但在使用多种类型时不起作用.我收到了一个错误

The Entity types ‘CampaginFeedback’ and ‘CampaignSurvey’ cannot share table ‘Campaign’ because they are not int he same type hierarchy
or do not have a valid one to one foreign key relationship with
matching primary keys between them.

以下是我的类的简化版本：

public class Campaign {
  [Key]
  public int CampaignId {get;set;}
  public string Name {get;set;}
  public virtual CampaignSurvey Survey {get;set;}
  public virtual CampaignFeedback Feedback {get;set;}
}

public class CampaignSurvey {
  [Key]
  public int CampaignId {get;set;}
  public string Question {get;set;}
  public string Answer {get;set;}
}

public class CampaignFeedback {
  [Key]
  public int CampaignId {get;set;}
  public string Feedback {get;set;}
}

protected override void OnModelCreating(DbModelBuilder modelBuilder) {
    modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
modelBuilder.Entity<Campaign>().HasRequired(c => c.Survey).WithRequiredPrincipal();
    modelBuilder.Entity<Campaign>().HasRequired(c => c.Feedback).WithRequiredPrincipal();
    modelBuilder.Entity<Campaign>().ToTable("Campaign");
    modelBuilder.Entity<CampaignSurvey>().ToTable("Campaign");
    modelBuilder.Entity<CampaignFeedback>().ToTable("Campaign");
}