尝试创建一个每天运行的事件，如下所示

Try creating a event which runs every day like below

CREATE EVENT myevent
  ON SCHEDULE AT CURRENT_TIMESTAMP + INTERVAL 1 DAY
  DO
    UPDATE my_table SET status ='closed'
    WHERE post_date > DATE_ADD(now(), INTERVAL -30 DAY)
    AND status='open'

-更新更改的语法

  CREATE EVENT myevent
  ON SCHEDULE EVERY 24 HOUR
  DO
    UPDATE my_table SET status ='closed'
    WHERE post_date > DATE_ADD(now(), INTERVAL -30 DAY)
    AND status='open'