如何在用户不活动、注销或会话结束后清除数据库字段

Question

I have a pivot table that is holding shopping cart type information like so

I set processing= true while I am getting payment information and count them along with the registered ones so inventory does not get oversold by simultaneous purchases. I can set processing=false if payment fails.

However in the cases where I don't get to finish payment processing...How do I reset processing to false when the user logs out, times out or ends their session or any other cases?

Answer 1

Depending on the user activity you could do all of the following:

1. Set SESSION variable and keep track of the time, if time expires then set the value to false
2. When user disconnects set value to false
3. Depending on the database you are using you could add a timed event to set the value to false.
   • For postgresql see pgAgent
   • For mysql see Event Scheduler