$sql = <<< __EOS__
        (
            SELECT dtb_products.*,
                dtb_products_class.product_class_id,
                dtb_products_class.product_type_id,
                dtb_products_class.product_code,
                dtb_products_class.stock,
                dtb_products_class.stock_unlimited,
                dtb_products_class.sale_limit,
                dtb_products_class.price01,
                dtb_products_class.price02,
                dtb_products_class.deliv_fee,
                dtb_products_class.point_rate,
                dtb_products_class.down_filename,dtb_products_class.down_realfilename,
                dtb_products_class.room1,
                dtb_products_class.classcategory_id1 AS classcategory_id, /* 削除 */
                dtb_products_class.classcategory_id1,
                dtb_products_class.classcategory_id2 AS parent_classcategory_id, /* 削除 */
                dtb_products_class.classcategory_id2,
                Tcc1.class_id as class_id,
                Tcc1.name as classcategory_name,
                Tcc2.class_id as parent_class_id,
                Tcc2.name as parent_classcategory_name
            FROM dtb_products
                LEFT JOIN dtb_products_class
                    ON dtb_products.product_id = dtb_products_class.product_id
                LEFT JOIN dtb_classcategory as Tcc1
                    ON dtb_products_class.classcategory_id1 = Tcc1.classcategory_id
                LEFT JOIN dtb_classcategory as Tcc2
                    ON dtb_products_class.classcategory_id2 = Tcc2.classcategory_id
            $where_clause
        ) as prdcls
__EOS__;