mysql中游标在存储过程中的详细用法_MySQL
昨天写的一个东东,分享下给大家。
drop PROCEDURE if exists sp_cleanUserData;
CREATE PROCEDURE `sp_cleanUserData`()
BEGIN
/*定义游标*/
declare v_dt bigint(20) default 0 ;
declare v_num INT DEFAULT 0;
/*游标循环到末尾时给定义的常量赋值*/
declare cur_userId CURSOR FOR select userId from user_level_info where DATE_SUB(CURDATE(), INTERVAL 60 DAY) >= firstLoginDate and lvdeclare CONTINUE HANDLER FOR SQLSTATE '02000' SET v_dt = -1;
/*开游标*/
OPEN cur_userId;
/*游标赋值*/
FETCH cur_userId INTO v_dt;
set v_num=1;
/* 循环体 */
WHILE ( v_dt !=-1 ) DO
/* 用户任务表 */
delete from task_user where user_id =v_dt;
/* 玩家公告 */
delete from user_action_info where userId =v_dt;
set v_num= v_num+1;
if v_num>100 then
commit;
set v_num=1;
end if;
/*读取下一行的数据*/
FETCH cur_userId INTO v_dt;
/*循环结束*/
END WHILE;
/*关闭游标*/
CLOSE cur_userId;
END;
call sp_cleanUserData;

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