Countdown timer

[markhuntley]

Hi,
im currently trying to use a countdown timer to update a certain part of my database.
so far i have set it up so that when the users clicks button X it stores the time + X.
I then have it checking the differance between the 2 times and using javascript to do the actual timer on the site. but i have got to the point where im not sure how to actual update the database when it gets to 0. the few things i have tried i did not work and now i am a bit unsure how to continue. The only other way i can think of is running a cron every few minutes to see if there done which is not exactly how i would like to do it. any ideas?
thanks
Mark

[HalfaBee]

Create a script to update the db and use JS to call the file.
If you need help to do this, search for AJAX.

[markhuntley]

that will allow me to have a timer in the background? will have a look at that now. thanks

[dewcansam]

Well, since this is along the lines of a question i was going to ask. Thought i would just add to it. I know it would be 'simple' to add JS functionality to a php page that would call another script when the timer ran up.
But, what about if the user closes the window or navigates away from the page ? the JS would quit running and thus the call to the second script would never happen.

I guess the best example would be with the new social networking sites there are 'online games' such as "Mobsters" / "Mob Wars" that add a functionality that even though the user is not logged in the timer keeps adding money to an account every hour. How is this accomplished ?
Any reading material ?

Thanks