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：文章源自很文博客https://www.hinwi.com/很文博客-https://www.hinwi.com/53955.html
- 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()文章源自很文博客https://www.hinwi.com/很文博客-https://www.hinwi.com/53955.html
文章源自很文博客https://www.hinwi.com/很文博客-https://www.hinwi.com/53955.html
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