entity framework - EF 0..1 to 0..1 relationship without shared primary key -

i have 2 entities configure optional 1-1 relationship (i.e. 0..1 0..1). using key on 1 entity, while having navigation properties in both directions.

consider following simplified example illustrate:

public class person  {      public int personid { get; set; }     public int? ticketid { get; set; }     public virtual ticket ticket { get; set; } }  public class ticket  {     public int ticketid { get; set; }     public virtual person person { get; set; } } 

there number of people, , number of tickets. person can possess @ 1 ticket. there people no ticket, , unclaimed tickets.

i thought following might work:

modelbuilder.entity<person>()     .hasoptional(p => p.ticket)     .withoptionalprincipal(t => t.person); 

but creates additional id on ticket table.

i know possible using 2 optional relationships, not ideal solution requires 2 calls savechanges, , not guarantee referential integrity (e.g. person1 own ticket1, ticket1 point person2).

similar questions have focussed on 1-0..1 relationship principal entity's primary key can used on dependent - not suitable either.

i using ef6 code-first.