This ticket will add the per (percentile) and std (standard deviation) aggregations to the stats, facet and timeseries Streaming Expressions. Syntax:
The stats function will also be reimplemented using JSON facets rather than the stats component as part of this ticket. The main reason is that JSON facets syntax is easier to work with for percentiles, but it also standardized are pushed down aggregations to JSON facets.
In a separate ticket per and std aggregations will be added to the rollup, hashRollup and nodes Streaming Expressions.