stateTracking() function

stateTracking() returns the cumulative count and duration of consecutive rows that match a predicate function that defines a state.

To return the cumulative count of consecutive rows that match the predicate, include the countColumn parameter. To return the cumulative duration of consecutive rows that match the predicate, include the durationColumn parameter. Rows that do not match the predicate function fn return -1 in the count and duration columns.

Function type signature

(
    <-tables: stream[A],
    fn: (r: A) => bool,
    ?countColumn: string,
    ?durationColumn: string,
    ?durationUnit: duration,
    ?timeColumn: string,
) => stream[B] where A: Record, B: Record

Parameters

fn

(Required) Predicate function to determine state.

countColumn

Column to store state count in.

If not defined, stateTracking() does not return the state count.

durationColumn

Column to store state duration in.

If not defined, stateTracking() does not return the state duration.

durationUnit

Unit of time to report state duration in. Default is 1s.

timeColumn

Column with time values used to calculate state duration. Default is _time.

tables

Input data. Default is piped-forward data (<-).

Examples

• Return a cumulative state count
• Return a cumulative state duration in milliseconds
• Return a cumulative state count and duration

Return a cumulative state count

data
    |> stateTracking(fn: (r) => r.state == "crit", countColumn: "count")

Return a cumulative state duration in milliseconds

data
    |> stateTracking(fn: (r) => r.state == "crit", durationColumn: "duration", durationUnit: 1ms)

Return a cumulative state count and duration

data
    |> stateTracking(fn: (r) => r.state == "crit", countColumn: "count", durationColumn: "duration")