Method for processing a purchase transaction using a plurality of transaction systems

Abstract

A method of processing a purchase transaction includes generating a transaction file containing a product code, which is transmitted from a user computing device when an image of a product code identifier is captured by the user computing device, a first user ID of the customer, and an indicator of whether or not the customer has opted in to receive electronic receipts. The method further includes generating an electronic receipt based on the transaction file, storing a conversion table containing the first and second user IDs of the customer, converting the first user ID contained in the transaction file to the second user ID based on the conversion table, when the indicator indicates that the customer has opted in, and storing the electronic receipt in association with the second user ID. The electronic receipt is transmitted in response to a request for electronic receipts associated with the second user ID.

What is claimed is: 
     
         1 . A memory device comprising:
 a memory unit;   a communication interface through which commands are received from a plurality of hosts; and   a controller configured to store the commands in a queue and determine an order of execution of the commands according to when the commands were added to the queue and whether or not the commands issued from a host that is designated as a priority host, wherein the controller determines the commands issued from the priority host to be executed prior to other commands that were not issued from the priority host, and determines the other commands to be executed in the order they were added to the queue.