Before that he was a researcher in the Database Group at Microsoft Research (2003-2008), a visiting researcher in the Stanford Database Group (1999-2002), and served as an invited expert at the World-Wide Web Consortium. He got an M.S. and a Ph.D. in Computer Science from the University of Leipzig, Germany. He received best paper awards at SIGMOD, ICDE and OSDI conferences, a 10-year Most Influential Paper Award at ICDE, and a best dissertation award from the German C.S. Society.