protected function isUpdate($input)
    {
        return (isset($input[$this->id_field_name]) && ! empty($input[$this->id_field_name]) );
    }
protected function isUpdate($input)
    {
        return (isset($input[$this->id_field_name]) && ! empty($input[$this->id_field_name]) );
    }
protected function isUpdate ( $ input ) { return ( isset ( $ input [ $ this -> id_field_name ] ) && ! empty ( $ input [ $ this -> id_field_name ] ) ) ; }
Check if the operation is update or create
@param $input
@return booelan $update update=true create=false
Check if the operation is update or create