protected function _reset()
    {
        $this->_table = '';
        $this->_prepare_sql = '';
        $this->_cols_str = ' * ';
        $this->_where_str = '';
        $this->_orderby_str = '';
        $this->_groupby_str = '';
        $this->_having_str = '';
        $this->_join_str = '';
        $this->_limit_str = '';
        $this->_insert_str = '';
        $this->_update_str = '';
        $this->_bind_params = [];
    }
protected function _reset()
    {
        $this->_table = '';
        $this->_prepare_sql = '';
        $this->_cols_str = ' * ';
        $this->_where_str = '';
        $this->_orderby_str = '';
        $this->_groupby_str = '';
        $this->_having_str = '';
        $this->_join_str = '';
        $this->_limit_str = '';
        $this->_insert_str = '';
        $this->_update_str = '';
        $this->_bind_params = [];
    }
protected function _reset ( ) { $ this -> _table = '' ; $ this -> _prepare_sql = '' ; $ this -> _cols_str = ' * ' ; $ this -> _where_str = '' ; $ this -> _orderby_str = '' ; $ this -> _groupby_str = '' ; $ this -> _having_str = '' ; $ this -> _join_str = '' ; $ this -> _limit_str = '' ; $ this -> _insert_str = '' ; $ this -> _update_str = '' ; $ this -> _bind_params = [ ] ; }
reset all attribute
memory-resident mode , need manual reset attr

@return  void
reset all attribute memory - resident mode need manual reset attr