创建存储过程proc1，根据指定的商品编号，返回该商品在购物车里的总数量。语句是: CREATE_proc1(codevarchar(50),_ncart int) SELECT SUM(cnum) 8010 FROM goods JOIN cart USING(gid) WHERE gcode=_ 调用存储过程，获得编号为“G0102”的商品在购物车里的总数量，并显示为:该商品已加购物车n个。语句是 proc1(G0102，); SELECT CONCAT(该商品已加购物车'，@nc个) AS结果;

DELIMITER $$
CREATE PROCEDURE proc1(IN code VARCHAR(50), OUT ncart INT)
BEGIN
SELECT SUM(cnum) INTO ncart
FROM goods JOIN cart USING(gid)
WHERE gcode = code;
END$$
DELIMITER ;

-- 调用存储过程
CALL proc1('G0102', @nc);
SELECT CONCAT('该商品已加购物车', @nc, '个') AS 结果;