/**
	 * Execute the query
	 *
	 * @access	private called by the base class
	 * @param	string	an SQL query
	 * @return	object
	 */
	function _execute($sql)
	{
		$sql = $this->_prep_query($sql);
		$result_id = $this->conn_id->prepare($sql);

		if (is_object($result_id) && $result_id->execute())
		{
			if (is_numeric(stripos($sql, 'SELECT')))
			{
				$this->affect_rows = count($result_id->fetchAll());
				$result_id->execute();
			}
			else
			{
				$this->affect_rows = $result_id->rowCount();
			}
			
			$result = $result_id;
		}
		else
		{
			$this->affect_rows = 0;
			$result = FALSE;
		}

		return $result;
	}