work with SQL Function in Entity Freamwork ?

[DbFunction("Dr_EmploEntities", "SelectEmployee")]
public virtual IQueryable<SelectEmployee_Result> SelectEmployee(Nullable<DateTime> frm_date, Nullable<DateTime> to_date)
{
    var frm_dateParameter = frm_date.HasValue ?
        new ObjectParameter("frm_date", frm_date) :
        new ObjectParameter("frm_date", typeof(DateTime));

    var to_dateParameter = to_date.HasValue ?
        new ObjectParameter("to_date", to_date) :
        new ObjectParameter("to_date", typeof(DateTime));

    return ((IObjectContextAdapter)this).ObjectContext.CreateQuery<SelectEmployee_Result>("[Dr_EmploEntities].[SelectEmployee](@frm_date, @to_date)", frm_dateParameter, to_dateParameter);
}

public DbSet<SelectEmployee_Result> SelectEmployee_Result { get; set; }

The type 'SelectEmployee_Result' is mapped as a complex type. The Set method, DbSet objects, and DbEntityEntry objects can only be used with entity types, not complex types.