Delete all rows within transaction: what would happen to other transactions?
The comment by a_horse_with_no_name is actually the answer, but since it was not posted as an answer, I'm not able to mark it so. I've completely forgotten about transaction isolation levels, I've asked the question in VoltDB forums and it appears that as long as make sure that stored procedures are local to nodes (sorry, this is a bit of a VoltDB terminology), that is, they don't process data across partitioned tables, this should work.