function lfGetRanking(){
				$conn = new SC_DBConn();
				$sql = "
				SELECT
						count(d.product_id) as rank,
						name,main_list_image,
						p.product_id as p_id
				FROM
						dtb_order_detail as d,
						vw_products_allclass as p
				WHERE
						d.product_id=p.product_id
				GROUP BY
						rank,
						name,main_list_image,
						p.product_id
				ORDER BY
						rank desc limit 10";		
						$list_data = $conn->getAll($sql);
				return $list_data;
		}