We demonstrate our prototype of the DBO database system. DBO is designed to facilitate scalable analytic processing over large data archives. DBO’s analytic processing performance is competitive with other database systems; however, unlike any other existing research or industrial system, DBO maintains a statistically meaningful guess to the final answer to a query from start to finish during query processing. This guess may be quite accurate after only a few seconds or minutes, while answering a query exactly may take hours. This can result in significant savings in both user and computer time, since a user can abort a query as soon as he or she is happy with the guess’ accuracy.