Hadoop and big data are often used synonymously, or at least mentioned in the same breath. I am reminded, for example, of a discussion in BITKOM's big data working group. One speaker virtually demanded that we deal almost exclusively with Hadoop, because this technology, and no other, was the basis for the entire debate. Of course, the speaker was harshly contradicted by representatives of analytical databases, sophisticated storage systems, in-memory technologies and the like. That was around two years ago.…