public function flush()
	{
		$this->where = null;
		$this->_aSelect = array();
		$this->_sFrom = '';
		$this->_sFromAs = '';
		$this->_aJoin = array();
		$this->_sUpdate = '';
		$this->_mWhere = array();
		$this->_aSet = array();
		$this->_sInsertInto = '';
		$this->_aValues = array();
		$this->_sDelete = '';
		$this->_aOrderBy = array();
		$this->_aGroupBy = array();
		$this->_iLimit = null;
		return $this;
	}