Webmaster Forum / ColdFusion / Advanced Techniques / September 2006

Hello,
I am working on an applicationt that is basically a virtual lineup to book
appointments.  Basically, users log in and are presented with the next
available time slot from the database.  They can either confirm the time or log
out.  When they confirm the time, the time is then marked as "taken" in the
database..

"times table"
slot_id
date
time
taken (bit)
offered (bit)

I realized yesterday that if Person A logged in and was offered time_slot = 1,
then if person B logged in before person A finished registering (confirm) then
Person B would also be offered time_slot = 1.  To overcome this, I created the
"offered" field.  Basically, as soon as a time is offered, the "offered" field
turns from 0 to 1.  So now, when Person A logs in, the time they are offered is
set to "1" and when person B logs in, they are given the next available time
that is not "offered" or "taken".  

I hope you are following.

What I am having trouble doing now is the following...
If person A logs in, is offered a time_slot and that time_slot becomes marked
"offered"...when they logout or close the window the time_slot remains marked
as "offered" i.e. "offered = 1".  I am trying to figure out a way to
automatically change the specific time_slot's "offered" field back to 0 in the
case that it is not confirmed.  Does this make any sense?  
Please help,
Thank you.