Mysql - 存储过程 - 定时删表

delimiter $
DROP PROCEDURE  if exists p_clearOldData;
/*
g_date_limit 时间限制, 如 2019_08 , 则删除 该时间之前的表 
g_date_length 时间格式的长度, 如 后缀时间是 2019_08, 则此处应该传 7  
*/
create PROCEDURE  p_clearOldData(in g_date_limit varchar(30), in g_date_length int ) 
begin 
    /*查询到的表名*/
    DECLARE g_table VARCHAR(100);

    /*查询到的表名对应的后缀时间*/
    DECLARE g_date VARCHAR(30) DEFAULT ‘‘;

    /*定义done, 用于跳出循环使用*/
    DECLARE done bit DEFAULT 0;

    /*声明游标*/
    DECLARE g_cursor CURSOR FOR select TABLE_NAME from INFORMATION_SCHEMA.TABLES  where TABLE_SCHEMA=‘tt_abc‘ and TABLE_NAME like ‘t_bk001_%‘;

    /*游标查询时, 如果找不到下一个了, 会将done置为1, 用于跳出 REPEAT 循环*/
  DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;

    /* 待执行动态sql */
    set @v_full_sql := ‘‘;

    /*打开游标*/
    open g_cursor;

    REPEAT

        FETCH g_cursor into g_table;

        set g_date = right(g_table, g_date_length);

        if g_date < g_date_limit then 

            set @v_full_sql = CONCAT(‘drop table if exists ‘,g_table);

             /*预编译此动态sql, 并存入stmt中*/
            PREPARE stmt from @v_full_sql;

            /*执行此动态sql, 此动态sql的作用, 是删除表*/
            execute stmt;    

            /*释放此资源*/
            DEALLOCATE PREPARE stmt;

        end if;

    /*结束repeat循环*/
    UNTIL done END REPEAT; 

    /*关闭游标*/
    close g_cursor;

select ‘OK‘;

end $
delimiter;

CREATE TABLE `t_bk001_2019_02` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8

call p_clearOldData(‘2019_03‘, 7);