$this->_select = array_merge($this->_select, $this->_customQuery->_select);
$this->_element = array_merge($this->_element, $this->_customQuery->_element);
$this->_tables = array_merge($this->_tables, $this->_customQuery->_tables);
$this->_select = array_merge($this->_select, $this->_customQuery->_select);
$this->_element = array_merge($this->_element, $this->_customQuery->_element);
$this->_tables = array_merge($this->_tables, $this->_customQuery->_tables);