public Users_Data AddUsers_Data(int user_goalId, DateTime date, double value)
 {
     try
     {
         var user_data = new Users_Data();
         user_data.Date = date;
         user_data.User_GoalId = user_goalId;
         user_data.Value = value;
         db.Users_Data.InsertOnSubmit(user_data);
         db.SubmitChanges();
         return user_data;
     }
     catch (Exception e)
     {
         return null;
     }
 }
 partial void DeleteUsers_Data(Users_Data instance);
 partial void InsertUsers_Data(Users_Data instance);
 partial void UpdateUsers_Data(Users_Data instance);
		private void detach_Users_Data(Users_Data entity)
		{
			this.SendPropertyChanging();
			entity.Users_Goals = null;
		}