Hi mungyun,

Sorry, I forgot to ask: is this a bespoke/home grown application, or is it off the shelf?

This is a simple applications logic problem as far as I can see. If it is a COTS application I would look at the manual and the settings options. If not then you will need to alter the process logic to suit your requirement.

It seems reasonable to me that once you have chosen a payment method then the cart should be locked. As soon as you leave the mall and go to the payment page that should also lock it.

My advice: check the program logic documentation and data flow diagrams. You might even get mileage out of the data dictionary as I presume the system sets flags? Of course you do use a structured design development and documentation methodology?..........don't you?

I think that it might be a good idea to walk through the whole business process logic?

To be honest I don't see what the problem is........... if people have enough brains to shop on line, they have the brains to know when to close their trolley? Then all they have to do is accept and pay, or cancel the whole transaction.