That is the only German phrase I ever used. I was on the island of Ischia, in the Gulf of Naples back in 1969. I passed a little out door bar/cafe on a walkway. The owner and his son were speaking German. I thought I would try out the only phrase I felt comfortable with. He didn't hesitate or look at me funny and I got my beer. I thought, WOW! that semester of German was finally good for something.