in reply to Processing ~1 Trillion records

I've only glanced at the various answers quickly, so maybe I'm off the mark, but:

My immediate reaction to needing to process that many rows is to try to parallelize the process. It will put a higher load on the DB, but that's what the DB is really good at. Obviously your dataset needs to be partitionable, but I can't imagine a dataset of that size that can't be split in some way.