1. 先执行下面的语句将维护计划的ID查出。

　　select * from sysmaintplan_plans

　　2. 将查出的ID填入到下面几句话中的''中，并执行。

　　delete from sysmaintplan_log where plan_id = ''

　　delete from sysmaintplan_subplans where plan_id = ''

　　delete from sysmaintplan_plans where id = ''