--创建测试表名create table job_table(run_date date);--创建存储过程create or replace procedure job_proc asbegin inser
--创建测试表名
create table job_table(run_date date);
--创建存储过程
create or replace procedure job_proc as
begin
insert into job_table (run_date) values (sysdate);
end;
--创建job并指定一分钟执行一次
declare
job number;
begin
dbms_job.submit(job,'job_proc;',sysdate,'TRUNC(sysdate,''mi'')+1/(24*60)');
end;
commit;
--暂停任务
--select job from user_jobs
找出job的id值,,然后使用下面的放语句停止任务。
begin
dbms_job.broken(584,true);
end;
--重启任务
begin
dbms_job.run(584);
end;
--删除任务
delete user_jobs where job=584;
drop procedure job_proc;
drop table job_table;
创建job后。系统即会在指定时间里自动调用该存储过程。
关于时间间隔的相关知识:
1.TRUNC(for dates)
TRUNC函数为指定元素而截去的日期值。
其具体的语法格式如下:
TRUNC(date[,fmt])
其中: date 一个日期值 fmt 日期格式,该日期将由指定的元素格式所截去。忽略它则由最近的日期截去
下面是该函数的使用情况:
TRUNC(TO_DATE('24-Nov-1999 08:00 pm'),'dd-mon-yyyy hh:mi am') ='24-Nov-1999 12:00:00 am'
TRUNC(TO_DATE('24-Nov-1999 08:37 pm','dd-mon-yyyy hh:mi am'),'hh') ='24-Nov-1999 08:00:00 am'
trunc(sysdate,'yyyy') --返回当年第一天.
trunc(sysdate,'mm') --返回当月第一天.
trunc(sysdate,'d') --返回当前星期的第一天.
trunc(sysdate,'dd')--返回当前年月日
trunc函数后面加的数字的单位是天。
每天凌晨0点0分:trunc(sysdate+1)
每天早上8点 trunc(sysdate+1)+1/3
每天早上8点30分 trunc(sysdate+1)+(8.5*60)/(24*60)
每天早上8点30分 trunc(sysdate+1)+8.5/24
每天早上8点30分 trunc(sysdate+1)+(8*60+30)/(24*60)

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