---
title: stateTracking() function
description: stateTracking() returns the cumulative count and duration of consecutive rows that match a predicate function that defines a state.
url: https://docs.influxdata.com/flux/v0/stdlib/universe/statetracking/
estimated_tokens: 3863
product: Flux
version: v0
---

# stateTracking() function

-   Flux 0.7.0+
-   View InfluxDB support

`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

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

For more information, see [Function type signatures](/flux/v0/function-type-signatures/).

## 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-count)
-   [Return a cumulative state duration in milliseconds](#return-a-cumulative-state-duration-in-milliseconds)
-   [Return a cumulative state count and duration](#return-a-cumulative-state-count-and-duration)

### Return a cumulative state count

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

[](#view-example-input-and-output)

View example input and output

#### Input data

| _time | _value | *tag | state |
| --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | -2 | t1 | ok |
| 2021-01-01T00:00:10Z | 10 | t1 | crit |
| 2021-01-01T00:00:20Z | 7 | t1 | crit |
| 2021-01-01T00:00:30Z | 17 | t1 | crit |
| 2021-01-01T00:00:40Z | 15 | t1 | crit |
| 2021-01-01T00:00:50Z | 4 | t1 | ok |

| _time | _value | *tag | state |
| --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | 19 | t2 | crit |
| 2021-01-01T00:00:10Z | 4 | t2 | ok |
| 2021-01-01T00:00:20Z | -3 | t2 | ok |
| 2021-01-01T00:00:30Z | 19 | t2 | crit |
| 2021-01-01T00:00:40Z | 13 | t2 | crit |
| 2021-01-01T00:00:50Z | 1 | t2 | ok |

#### Output data

| _time | _value | *tag | state | count |
| --- | --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | -2 | t1 | ok | -1 |
| 2021-01-01T00:00:10Z | 10 | t1 | crit | 1 |
| 2021-01-01T00:00:20Z | 7 | t1 | crit | 2 |
| 2021-01-01T00:00:30Z | 17 | t1 | crit | 3 |
| 2021-01-01T00:00:40Z | 15 | t1 | crit | 4 |
| 2021-01-01T00:00:50Z | 4 | t1 | ok | -1 |

| _time | _value | *tag | state | count |
| --- | --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | 19 | t2 | crit | 1 |
| 2021-01-01T00:00:10Z | 4 | t2 | ok | -1 |
| 2021-01-01T00:00:20Z | -3 | t2 | ok | -1 |
| 2021-01-01T00:00:30Z | 19 | t2 | crit | 1 |
| 2021-01-01T00:00:40Z | 13 | t2 | crit | 2 |
| 2021-01-01T00:00:50Z | 1 | t2 | ok | -1 |

### Return a cumulative state duration in milliseconds

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

[](#view-example-input-and-output)

View example input and output

#### Input data

| _time | _value | *tag | state |
| --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | -2 | t1 | ok |
| 2021-01-01T00:00:10Z | 10 | t1 | crit |
| 2021-01-01T00:00:20Z | 7 | t1 | crit |
| 2021-01-01T00:00:30Z | 17 | t1 | crit |
| 2021-01-01T00:00:40Z | 15 | t1 | crit |
| 2021-01-01T00:00:50Z | 4 | t1 | ok |

| _time | _value | *tag | state |
| --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | 19 | t2 | crit |
| 2021-01-01T00:00:10Z | 4 | t2 | ok |
| 2021-01-01T00:00:20Z | -3 | t2 | ok |
| 2021-01-01T00:00:30Z | 19 | t2 | crit |
| 2021-01-01T00:00:40Z | 13 | t2 | crit |
| 2021-01-01T00:00:50Z | 1 | t2 | ok |

#### Output data

| _time | _value | *tag | state | duration |
| --- | --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | -2 | t1 | ok | -1 |
| 2021-01-01T00:00:10Z | 10 | t1 | crit | 0 |
| 2021-01-01T00:00:20Z | 7 | t1 | crit | 10000 |
| 2021-01-01T00:00:30Z | 17 | t1 | crit | 20000 |
| 2021-01-01T00:00:40Z | 15 | t1 | crit | 30000 |
| 2021-01-01T00:00:50Z | 4 | t1 | ok | -1 |

| _time | _value | *tag | state | duration |
| --- | --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | 19 | t2 | crit | 0 |
| 2021-01-01T00:00:10Z | 4 | t2 | ok | -1 |
| 2021-01-01T00:00:20Z | -3 | t2 | ok | -1 |
| 2021-01-01T00:00:30Z | 19 | t2 | crit | 0 |
| 2021-01-01T00:00:40Z | 13 | t2 | crit | 10000 |
| 2021-01-01T00:00:50Z | 1 | t2 | ok | -1 |

### Return a cumulative state count and duration

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

[](#view-example-input-and-output)

View example input and output

#### Input data

| _time | _value | *tag | state |
| --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | -2 | t1 | ok |
| 2021-01-01T00:00:10Z | 10 | t1 | crit |
| 2021-01-01T00:00:20Z | 7 | t1 | crit |
| 2021-01-01T00:00:30Z | 17 | t1 | crit |
| 2021-01-01T00:00:40Z | 15 | t1 | crit |
| 2021-01-01T00:00:50Z | 4 | t1 | ok |

| _time | _value | *tag | state |
| --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | 19 | t2 | crit |
| 2021-01-01T00:00:10Z | 4 | t2 | ok |
| 2021-01-01T00:00:20Z | -3 | t2 | ok |
| 2021-01-01T00:00:30Z | 19 | t2 | crit |
| 2021-01-01T00:00:40Z | 13 | t2 | crit |
| 2021-01-01T00:00:50Z | 1 | t2 | ok |

#### Output data

| _time | _value | *tag | state | count | duration |
| --- | --- | --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | -2 | t1 | ok | -1 | -1 |
| 2021-01-01T00:00:10Z | 10 | t1 | crit | 1 | 0 |
| 2021-01-01T00:00:20Z | 7 | t1 | crit | 2 | 10 |
| 2021-01-01T00:00:30Z | 17 | t1 | crit | 3 | 20 |
| 2021-01-01T00:00:40Z | 15 | t1 | crit | 4 | 30 |
| 2021-01-01T00:00:50Z | 4 | t1 | ok | -1 | -1 |

| _time | _value | *tag | state | count | duration |
| --- | --- | --- | --- | --- | --- |
| 2021-01-01T00:00:00Z | 19 | t2 | crit | 1 | 0 |
| 2021-01-01T00:00:10Z | 4 | t2 | ok | -1 | -1 |
| 2021-01-01T00:00:20Z | -3 | t2 | ok | -1 | -1 |
| 2021-01-01T00:00:30Z | 19 | t2 | crit | 1 | 0 |
| 2021-01-01T00:00:40Z | 13 | t2 | crit | 2 | 10 |
| 2021-01-01T00:00:50Z | 1 | t2 | ok | -1 | -1 |

[transformations](/flux/v0/tags/transformations/)