raw_aggregate round-trip.
Expected output
percentile accepts only latency / node_latency and n in (50, 75, 95, 99). A single-dim group_by(...) flattens to a dict[str, float]; add a second dimension and you get an AggregationResult with nested buckets. group_by(GroupBy.TIME, ...) requires an interval.
See also
Query basics
Scope before you aggregate.
Table & export
Project raw rows and export them.
Reference
AggregationField, GroupBy, Interval, Percentile.