Think credit card transactions, first, to write unionfs?

Setup a mysql database, with all the array names for credit card number, expire date, user name, user address, user statement dated, amount of credit unused, amount of credit approved to be spent for a merchandise name, store name and address for payment.

This user AT is in the local server in Massachusetts, USA. But he went to London and charged for an item, a pair of pants $2000; the store is Daks in soho district, today. The credit card issuer is in NYC. And Visa has 100 servers indexed A-Z. Which unionfs in which computer should have the updated info immediately? And how?

Once, the workflow is determined, a script is written for unionfs of Visa credit card servers. Data will be transmitted via dotnet packets on the internet with ip address of each server.

Knopper will have fun with this, but Visa runs 150,000 credit card transaction per second. Still sometimes, we have to stand in front of POS computer to wait for approval of our credit?