为什么我在EF中获得双柱？

Question

为什么我的列数会增加一倍，如图所示：

如何将此列合并为一列而不是两列？

public class User
{
    [Key]
    public long id { get; set; }
}

public class Woman : User
{
    public Woman()
    {
        s = new SharedManWoman();
        Clone = new Clone.CWoman();
    }

    public Clone.CWoman Clone { get; set; }
    public SharedManWoman s { get; set; }
}

public class Man : User
{
    public Man()
    {
        s = new SharedManWoman();
        Clone = new Clone.CMan();
    }

    public Clone.CMan Clone { get; set; }
    public SharedManWoman s { get; set; }
}

public class SharedManWoman
{
    [Key]
    public long tableId { get; set; }
}

public class CUser
{
    [Key]
    public long id { get; set; }
}

public class CWoman : CUser {}

public class CMan : CUser {}

Answer 1

这两个都是在单独的派生类中定义的，因为它们是导航属性，所以它们为每个派生出一个外键：

public Clone.CWoman Clone { get; set; }

public Clone.CMan Clone { get; set; }

你可以将它们移到基类而取消CWoman / CMan，而不是使它成为CUser类型：

public class User
{
    [Key]
    public long id { get; set; }
    public Clone.CUser Clone { get; set; }

}

那应该摆脱其中一个重复的FK，但不确定这个解决方案是否适合你想要完成的任务。