Unable to determine the principle end of an association

Question

Using EF5 Code first, I have two classes:

[Table(\"UserProfile\")]
public class UserProfile {

    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)         


        

Answer 1

The trick with 1:1 in EF is the dependant table MUST have the same primary key. The Primary tables has the DB generated ID. The dependant uses DatabaseGeneratedOption.None !

so the fluentAPI for the dependant table

 {
  // map for Dependant
  // Relationship
        this.HasKey(t => t.Id);
        // Properties
        //Id is an int allocated by DB but controller via Primary here
        this.Property(t => t.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.None); // from parent
        entity.HasRequired(t => t.NAV_PROP_TO_PRIMARY)
              .WithOptional(t => t.NAV_PROP_DEPENDANT) // if it is declared. NOT required.
              .WillCascadeOnDelete(true);   // as appropriate
 }   

 {
     //map for Primary
     // Primary Key
     this.HasKey(t => t.Id);

     // Properties
     //Id is an int allocated by DB
    this.Property(t => t.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity); // default to db generated

 }


public class Dependant{ 
   public  virtual int Id { set; get; }
   //... other props
   public virtual Primary Primary {get; set;}   // nav to primary
} 

public class Primary{ 
   public  virtual int Id { set; get; }

}