title: Entity Framework: Problem associating entities with nullable field
body: <p>I'm using Entity Framework, and I'm trying to associate an entity that was created from a database table with an entity that was created from a database view.  Because Entity Framework is not able to infer the relationships between a database table and a view automatically, I'm using the entity designer to construct an "association" between the entities.  However, if the foreign key is a nullalbe type, I get the following error:</p>
  
  <p>Error 113: Multiplicity is not valid in Role 'Company' in relationship 'UsersView'. 
  Because all the properties in the Dependent Role are nullable, multiplicity of the Principal Role must be '0..1'.</p>
  
  <p>In my scenario, I have a CompanyId foreign key in my UsersView that's nullable (i.e. users may not have a company).  Creating an association with a nullable foreign key was never a problem with Linq 2 SQL.  Does anyone know how I can get around this problem in Entity Framework?</p>
  
  <p>Thanks in advance.</p>