asp.net – 实体框架：如何解决“FOREIGN KEY约束可能导致循环或

我有一个Office表与医生和秘书表有一对多的关系。两个最后的表都是从Employee表派生的，它与sqlmembershipprovider创建的预定义Users表具有共享主键关系。看起来在Users表和Roles表之间有许多关系，我没有任何手。

我的问题是在我的Employee表和用户表之间创建一个(零，一) – (一)关系，我结束了它们之间的共享主键关系和提出的错误。 (有问题的更好的解决方案吗？)

这里是错误：

Introducing FOREIGN KEY constraint
‘FK_dbo.aspnet_UsersInRoles_dbo.aspnet_Users_UserId’ on table
‘aspnet_UsersInRoles’ may cause cycles or multiple cascade paths.
Specify ON DELETE NO ACTION or ON UPDATE NO ACTION,or modify other
FOREIGN KEY constraints. Could not create constraint. See previous
errors.

这里是我的代码和成员代码后逆向工程：

public class Office
{
    public Office()
    {
        this.Doctors = new HashSet<Doctor>();
        this.Secretaries = new HashSet<Secretary>();
    }

    [Key]
    public System.Guid OfficeId { get; set; }
    public virtual ICollection<Doctor> Doctors { get; set; }
    public virtual ICollection<Secretary> Secretaries { get; set; }
}

public class Employee
{
    [Key,ForeignKey("User")]
    [DatabaseGenerated(DatabaseGeneratedOption.None)]
    public System.Guid Id { get; set; }
    public string Name { get; set; }

    [ForeignKey("Office")]
    public System.Guid OfficeId { get; set; }

    // shared primary key 
    public virtual aspnet_Users User { get; set; }

    public virtual Office Office { get; set; }
}

public class Doctor :Employee
{
    public Doctor()
    {
        this.Expertises = new HashSet<Expertise>();
    }
    //the rest..    
    public virtual ICollection<Expertise> Expertises { get; set; }
}

public class Secretary : Employee
{
    // blah blah
}

public class aspnet_Users
{
    public aspnet_Users()
    {
        this.aspnet_Roles = new List<aspnet_Roles>();
    }

    public System.Guid ApplicationId { get; set; }
    public System.Guid UserId { get; set; }
    //the rest..
    public virtual aspnet_Applications aspnet_Applications { get; set; }
    public virtual ICollection<aspnet_Roles> aspnet_Roles { get; set; }
}

public class aspnet_Roles
{
    public aspnet_Roles()
    {
        this.aspnet_Users = new List<aspnet_Users>();
    }

    public System.Guid ApplicationId { get; set; }
    public System.Guid RoleId { get; set; }
    //the rest..
    public virtual aspnet_Applications aspnet_Applications { get; set; }
    public virtual ICollection<aspnet_Users> aspnet_Users { get; set; }
}

编辑：和关系更深，在用户表和应用程序表之间有一个多对一的关系，也在角色和应用程序之间。