Hi, there no guarantees for the fields other than the summed field (and eventual key fields). I think in practice it's either the fields from the first or last record but I wouldn't rely on that.
Cheers, Aljoscha On Sat, 9 Apr 2016 at 03:19 Elias Levy <fearsome.lucid...@gmail.com> wrote: > I am wondering about the expected behavior of the sum method. Obviously > it sums a specific field in a tuple or POJO. But what should one expect in > other fields? Does sum keep the first field, last field or there aren't > any guarantees? >
