mysql - Event scheduler MySql without expired time

Question

I read article about the event scheduler on MySql.Then I got this structure,

CREATE
[DEFINER = { user | CURRENT_USER }]
EVENT
[IF NOT EXISTS]
event_name
ON SCHEDULE schedule
[ON COMPLETION [NOT] PRESERVE]
[ENABLE | DISABLE | DISABLE ON SLAVE]
[COMMENT 'comment']
DO event_body;

I got some interested thing to know about it, 1. Could this event schedule havent expired time? 2. What is the ENABLE | DISABLE | DISABLE ON SLAVE mean?

Any respon will be appreciate,Thx.

Answer 1

1. 这个活动时间表会不会过期？利用 -ON COMPLETION PRESERVE
2. 什么是启用 | 禁用 | DISABLE ON SLAVE 是什么意思？ENABLE/DISABLE - 表示事件处于活动/非活动状态。

DISABLE ON SLAVE（来自文档）-为复制从属上的事件状态设置，以指示该事件是在主控上创建并复制到从属，但不在从属上执行。