创建job 报错 PLS-00103: 出现符号 "MI"

VARIABLE jobno number;
begin
DBMS_JOB.SUBMIT(:jobno, 'MYPROC; ', SYSDATE, 'trunc(SYSDATE, 'mi ') + 1/1440 ');
commit;
end;

------解决方法--------------------------------------------------------
VARIABLE jobno number;
BEGIN
dbms_job.submit(:jobno,
'MYPROC; ',
SYSDATE,
'trunc(SYSDATE, ' 'mi ' ') + 1/1440 ');
COMMIT;
END;

字符串常量中的单引号要用两个单引号来跳脱.