Crontab Extension

hi all ,

  i am trying to use crontab to schedule update in my Db and had read through  [url="http://www.yiiframew...ion/yii-crontab"]crontab[/url],but i was little confused where to use the given codes 

Thanks in advance

It works while using Command prompt manually ,but how can i do it without manual process?.

please guide me in this