Linq 0..1-one association

Hi I have a big problem with Linq. I have to do a 0. .1-to-one association within this two classes:

[Table(Name = "TB_Points")]
public class Point
{
       开发者_StackOverflow private int _ID = 0;
        [Column(Storage = "_ID", DbType = "Int NOT NULL IDENTITY", IsPrimaryKey = true, IsDbGenerated = true)]
        public int ID { get { return this._ID; } }
}

[Table(Name = "TB_TimePoint")]
public class TimePoint
{
        private int _ID = 0;
        [Column(Storage = "_ID", DbType = "Int NOT NULL IDENTITY", IsPrimaryKey = true, IsDbGenerated = true)]
        public int ID { get { return this._ID; } }

        //here is the association
        public Point Pos { get; set; }
}

The Point is a my general class so some times a Point can exists without the TimePoint, so there is null in the association. And I don't need to know about the TimePoint from the Point class. All my attempts failed. I don't know whether the problem is in IsDbGenerated = true or in other stuff. Please help. Thx

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The typical approach is to make TimePoint's primary key also be a foreign key to the Point's primary key.