The notable difference here is that this presents a lot more optimization potential, as the entire pipeline can conceivably be applied in one pass through the table.
The UDDSketch (default) implementation will allow rolling percentiles, though we still need a bit of work on our end to support it. There isn't a way to do this with TDigest however.
We actually haven't been running against any limits here. One thing to keep in mind is that postgres remote-fetch operations aren't tuple-at-a-time, so this shouldn't be a bottleneck for our multi-node operations.
SELECT device_id, arrow_run_pipeline(timevector(ts, val), arrow_add_element(sort(), arrow_add_element(delta(), arrow_add_element(abs(), sum())));
The notable difference here is that this presents a lot more optimization potential, as the entire pipeline can conceivably be applied in one pass through the table.