How Handle BUG while web application is run


actually this is not a YII function problem … i want to know ,

the programmer see error(bug) after he upload site live (ex:login faild).in local machine doesn’t display like this bug while develop & testing . problem is, now this web application use by viewers. what is best way handle like this problem .how to debug live code & fixed without site is down

thank you

Sometimes, on really small systems, I usually add some code in Error page which sends me an email containing stack output and error in general. Other approach is to write errors in file or in DB depending on your preferences.