MySQL游标嵌套循环存储过程

BEGIN
   DECLARE _uuid VARCHAR(60); 
   DECLARE _labels varchar(100);
   DECLARE done int DEFAULT 0;
   DECLARE _result VARCHAR(200);
   DECLARE _name VARCHAR(60);
   DECLARE token int DEFAULT 0;
   
   #定义游标
   DECLARE rs_cursor CURSOR FOR SELECT uuid FROM product;
   #游标结束条件
   DECLARE CONTINUE HANDLER FOR NOT FOUND SET done=1;
    #打开游标
   OPEN rs_cursor;
   cursor_loop:LOOP
     FETCH rs_cursor INTO _uuid;
		 IF done = 1 THEN 
		      LEAVE cursor_loop; 
		 END IF;
     SET _result='',_name='';
     BEGIN 
         DECLARE 
		rs_cursor_item CURSOR 
	FOR 
		select f.name as name from func_prod_map p LEFT JOIN product_func f on p.func_uuid = f.uuid WHERE p.product_uuid = _uuid;
					#游标结束条件
	DECLARE CONTINUE HANDLER FOR NOT FOUND SET token=1; 
        OPEN rs_cursor_item;
	   REPEAT
		FETCH rs_cursor_item INTO _name;
           
	   #SELECT _name;
           IF token <> 1 THEN
		SET _result = CONCAT(_result,_name,',');
           END IF;
          
	 #UNTIL token=1 END REPEAT ;
         UNTIL token = 1 END REPEAT;
	 CLOSE rs_cursor_item;
         SET token=0;
         UPDATE product SET labels = _result WHERE uuid = _uuid; 
         SET _result='',_name='';
     END;
   END LOOP;
   CLOSE rs_cursor;
END