c# - How to map a 1:1 (optional) mapping in Entity Framework -

i have class like:

public class employee {     [column("employee_id")]     public int employeid {get;set;} }   public class location {     [column("employee_location_id")]     public int id {get;set;}      [column("employee_id")]     public int employeeid {get;set;} } 

on employee class, added virtual property:

public virtual location location {get;set;} 

i trying add optional property (lazy loaded), employee may have or or 1 location.

i'm getting error when mvc application loads now:

system.data.sqlclient.sqlexception: invalid column name 'location_id'. 

have tried specifying fk/navigation properties explicitly?

public int locationid { get; set; } [foreignkey("locationid")] public virtual location location { get; set; } 

navigation property not loading when id of related object populated