MySQL的存储过程写法和"Cursor"的使用

 来自:

本文中介绍了一个MySQL的存储过程，其中涉及Cursor的使用，示例如下： CREATE PROCEDURE `justifyGroupNum`() NOT DETERMINISTIC SQL SECURITY DEFINER COMMENT '' BEGIN /*how to run:call justifyGroupNum()*/ DECLARE p_group_id int; declare p_num int; declare stopFlag int; DECLARE cursor_name CURSOR FOR select c_group_id,count(*) as num from `t_group_member` where c_valid in (3,4) group by c_group_id; DECLARE CONTINUE HANDLER FOR NOT FOUND set stopFlag=1; OPEN cursor_name; REPEAT FETCH cursor_name INTO p_group_id,p_num; begin update t_groupinfo set c_member_number=p_num where c_group_id=p_group_id; end; UNTIL stopFlag = 1 END REPEAT; CLOSE cursor_name; END; 总结： 1、注意设置游标的countinue handler：DECLARE CONTINUE HANDLER FOR NOT FOUND set stopFlag=1; 2、注意REPEAT和UTILE [停止条件] END REPEAT的使用，否则不会循环； 3、如何RUN，输入并执行：call justifyGroupNum()