Grouping by events with not unique ID

[Anaisdg]

Hello @XXYYZZ,
You’re correct this is non trivial with flux.
Here I did something similar

Use "markers" to define beg. and end of a period, then do calcs on data within that period

Okay this worked: import "math" import outer "join" import "internal/debug" data = from(bucket: "noaa") |> range(start: v.timeRangeStart, stop: v.timeRangeStop) |> filter(fn: (r) => r["_measurement"] == "h2o_feet") |> filter(fn: (r) => r["_field"] == "water_level") |> filter(fn: (r) => r["location"] == "coyote_creek") |> keep(columns: ["_time", "_value"]) |> limit(n: 400) // |> yield(name: "raw") derr = data // unit for the time in between timestamps |> derivative(unit: 6m) |>…

But yikes.

I honestly would recommend querying the data with API or client library and doing this processing elsewhere and writing the data back into influxdb.

Sorry I can’t be of better assistance.