This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
You could add a field to your database. If the amount of data you need to store is both small and not sensitive in nature, you could store it in a cookie as well. Of course, if you use a cookie, this information will only be seen if the user logs in from the same machine next time.