---
title: FlattenNode (Kapacitor TICKscript node)
description: FlattenNode flattens a set of points on specific dimensions.
note: Auto generated by tickdoc

menu:
  kapacitor_1_4:
    name: FlattenNode
    identifier: flatten_node
    weight: 100
    parent: TICKscript nodes
---
### Constructor

| Chaining Method | Description |
|:---------|:---------|
| **[flatten](#descr) ( )** | Flatten points with similar times into a single point.  |

### Property Methods

| Setters | Description |
|:---|:---|
| **[delimiter](#delimiter) ( `value` `string`)** | The delimiter between field name parts  |
| **[dropOriginalFieldName](#droporiginalfieldname) ( `drop` `...bool`)** | DropOriginalFieldName indicates whether the original field name should be dropped when constructing the final field name.  |
| **[on](#on) ( `dims` `...string`)** | Specify the dimensions on which to flatten the points.  |
| **[tolerance](#tolerance) ( `value` `time.Duration`)** | The maximum duration of time that two incoming points can be apart and still be considered to be equal in time. The joined data point's time will be rounded to the nearest multiple of the tolerance duration.  |



### Chaining Methods
[Alert](/kapacitor/v1.4/nodes/flatten_node/#alert), [Barrier](/kapacitor/v1.4/nodes/flatten_node/#barrier), [Bottom](/kapacitor/v1.4/nodes/flatten_node/#bottom), [Combine](/kapacitor/v1.4/nodes/flatten_node/#combine), [Count](/kapacitor/v1.4/nodes/flatten_node/#count), [CumulativeSum](/kapacitor/v1.4/nodes/flatten_node/#cumulativesum), [Deadman](/kapacitor/v1.4/nodes/flatten_node/#deadman), [Default](/kapacitor/v1.4/nodes/flatten_node/#default), [Delete](/kapacitor/v1.4/nodes/flatten_node/#delete), [Derivative](/kapacitor/v1.4/nodes/flatten_node/#derivative), [Difference](/kapacitor/v1.4/nodes/flatten_node/#difference), [Distinct](/kapacitor/v1.4/nodes/flatten_node/#distinct), [Ec2Autoscale](/kapacitor/v1.4/nodes/flatten_node/#ec2autoscale), [Elapsed](/kapacitor/v1.4/nodes/flatten_node/#elapsed), [Eval](/kapacitor/v1.4/nodes/flatten_node/#eval), [First](/kapacitor/v1.4/nodes/flatten_node/#first), [Flatten](/kapacitor/v1.4/nodes/flatten_node/#flatten), [GroupBy](/kapacitor/v1.4/nodes/flatten_node/#groupby), [HoltWinters](/kapacitor/v1.4/nodes/flatten_node/#holtwinters), [HoltWintersWithFit](/kapacitor/v1.4/nodes/flatten_node/#holtwinterswithfit), [HttpOut](/kapacitor/v1.4/nodes/flatten_node/#httpout), [HttpPost](/kapacitor/v1.4/nodes/flatten_node/#httppost), [InfluxDBOut](/kapacitor/v1.4/nodes/flatten_node/#influxdbout), [Join](/kapacitor/v1.4/nodes/flatten_node/#join), [K8sAutoscale](/kapacitor/v1.4/nodes/flatten_node/#k8sautoscale), [KapacitorLoopback](/kapacitor/v1.4/nodes/flatten_node/#kapacitorloopback), [Last](/kapacitor/v1.4/nodes/flatten_node/#last), [Log](/kapacitor/v1.4/nodes/flatten_node/#log), [Max](/kapacitor/v1.4/nodes/flatten_node/#max), [Mean](/kapacitor/v1.4/nodes/flatten_node/#mean), [Median](/kapacitor/v1.4/nodes/flatten_node/#median), [Min](/kapacitor/v1.4/nodes/flatten_node/#min), [Mode](/kapacitor/v1.4/nodes/flatten_node/#mode), [MovingAverage](/kapacitor/v1.4/nodes/flatten_node/#movingaverage), [Percentile](/kapacitor/v1.4/nodes/flatten_node/#percentile), [Sample](/kapacitor/v1.4/nodes/flatten_node/#sample), [Shift](/kapacitor/v1.4/nodes/flatten_node/#shift), [Sideload](/kapacitor/v1.4/nodes/flatten_node/#sideload), [Spread](/kapacitor/v1.4/nodes/flatten_node/#spread), [StateCount](/kapacitor/v1.4/nodes/flatten_node/#statecount), [StateDuration](/kapacitor/v1.4/nodes/flatten_node/#stateduration), [Stats](/kapacitor/v1.4/nodes/flatten_node/#stats), [Stddev](/kapacitor/v1.4/nodes/flatten_node/#stddev), [Sum](/kapacitor/v1.4/nodes/flatten_node/#sum), [SwarmAutoscale](/kapacitor/v1.4/nodes/flatten_node/#swarmautoscale), [Top](/kapacitor/v1.4/nodes/flatten_node/#top), [Union](/kapacitor/v1.4/nodes/flatten_node/#union), [Where](/kapacitor/v1.4/nodes/flatten_node/#where), [Window](/kapacitor/v1.4/nodes/flatten_node/#window)
<a id='descr'/><hr/><br/>
### Description

Flatten a set of points on specific dimensions.
For example given two points:

m,host=A,port=80 bytes=3512
m,host=A,port=443 bytes=6723

Flattening the points on `port` would result in a single point:

m,host=A 80.bytes=3512,443.bytes=6723

Example:


```javascript
        |flatten()
            .on('port')
```

If flattening on multiple dimensions the order is preserved:

m,host=A,port=80 bytes=3512
m,host=A,port=443 bytes=6723
m,host=B,port=443 bytes=7243

Flattening the points on `host` and `port` would result in a single point:

m A.80.bytes=3512,A.443.bytes=6723,B.443.bytes=7243

Example:


```javascript
        |flatten()
            .on('host', 'port')
```


Since flattening points creates dynamically named fields in general it is expected
that the resultant data is passed to a UDF or similar for custom processing.


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Properties
----------

Property methods modify state on the calling node.
They do not add another node to the pipeline, and always return a reference to the calling node.
Property methods are marked using the `.` operator.


### Delimiter

The delimiter between field name parts


```javascript
flatten.delimiter(value string)
```

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### DropOriginalFieldName

DropOriginalFieldName indicates whether the original field name should
be dropped when constructing the final field name.


```javascript
flatten.dropOriginalFieldName(drop ...bool)
```

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### On

Specify the dimensions on which to flatten the points.


```javascript
flatten.on(dims ...string)
```

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### Tolerance

The maximum duration of time that two incoming points
can be apart and still be considered to be equal in time.
The joined data point's time will be rounded to the nearest
multiple of the tolerance duration.


```javascript
flatten.tolerance(value time.Duration)
```

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Chaining Methods
----------------

Chaining methods create a new node in the pipeline as a child of the calling node.
They do not modify the calling node.
Chaining methods are marked using the `|` operator.


### Alert

Create an alert node, which can trigger alerts.


```javascript
flatten|alert()
```

Returns: [AlertNode](/kapacitor/v1.4/nodes/alert_node/)

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### Barrier

Create a new Barrier node that emits a BarrierMessage periodically

One BarrierMessage will be emitted every period duration


```javascript
flatten|barrier()
```

Returns: [BarrierNode](/kapacitor/v1.4/nodes/barrier_node/)

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### Bottom

Select the bottom `num` points for `field` and sort by any extra tags or fields.


```javascript
flatten|bottom(num int64, field string, fieldsAndTags ...string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Combine

Combine this node with itself. The data is combined on timestamp.


```javascript
flatten|combine(expressions ...ast.LambdaNode)
```

Returns: [CombineNode](/kapacitor/v1.4/nodes/combine_node/)

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### Count

Count the number of points.


```javascript
flatten|count(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### CumulativeSum

Compute a cumulative sum of each point that is received.
A point is emitted for every point collected.


```javascript
flatten|cumulativeSum(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Deadman

Helper function for creating an alert on low throughput, a.k.a. deadman's switch.

- Threshold -- trigger alert if throughput drops below threshold in points/interval.
- Interval -- how often to check the throughput.
- Expressions -- optional list of expressions to also evaluate. Useful for time of day alerting.

Example:


```javascript
    var data = stream
        |from()...
    // Trigger critical alert if the throughput drops below 100 points per 10s and checked every 10s.
    data
        |deadman(100.0, 10s)
    //Do normal processing of data
    data...
```

The above is equivalent to this
Example:


```javascript
    var data = stream
        |from()...
    // Trigger critical alert if the throughput drops below 100 points per 10s and checked every 10s.
    data
        |stats(10s)
            .align()
        |derivative('emitted')
            .unit(10s)
            .nonNegative()
        |alert()
            .id('node \'stream0\' in task \'{{ .TaskName }}\'')
            .message('{{ .ID }} is {{ if eq .Level "OK" }}alive{{ else }}dead{{ end }}: {{ index .Fields "emitted" | printf "%0.3f" }} points/10s.')
            .crit(lambda: "emitted" <= 100.0)
    //Do normal processing of data
    data...
```

The `id` and `message` alert properties can be configured globally via the 'deadman' configuration section.

Since the [AlertNode](/kapacitor/v1.4/nodes/alert_node/) is the last piece it can be further modified as usual.
Example:


```javascript
    var data = stream
        |from()...
    // Trigger critical alert if the throughput drops below 100 points per 10s and checked every 10s.
    data
        |deadman(100.0, 10s)
            .slack()
            .channel('#dead_tasks')
    //Do normal processing of data
    data...
```

You can specify additional lambda expressions to further constrain when the deadman's switch is triggered.
Example:


```javascript
    var data = stream
        |from()...
    // Trigger critical alert if the throughput drops below 100 points per 10s and checked every 10s.
    // Only trigger the alert if the time of day is between 8am-5pm.
    data
        |deadman(100.0, 10s, lambda: hour("time") >= 8 AND hour("time") <= 17)
    //Do normal processing of data
    data...
```



```javascript
flatten|deadman(threshold float64, interval time.Duration, expr ...ast.LambdaNode)
```

Returns: [AlertNode](/kapacitor/v1.4/nodes/alert_node/)

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### Default

Create a node that can set defaults for missing tags or fields.


```javascript
flatten|default()
```

Returns: [DefaultNode](/kapacitor/v1.4/nodes/default_node/)

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### Delete

Create a node that can delete tags or fields.


```javascript
flatten|delete()
```

Returns: [DeleteNode](/kapacitor/v1.4/nodes/delete_node/)

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### Derivative

Create a new node that computes the derivative of adjacent points.


```javascript
flatten|derivative(field string)
```

Returns: [DerivativeNode](/kapacitor/v1.4/nodes/derivative_node/)

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### Difference

Compute the difference between points independent of elapsed time.


```javascript
flatten|difference(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Distinct

Produce batch of only the distinct points.


```javascript
flatten|distinct(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Ec2Autoscale

Create a node that can trigger autoscale events for a ec2 autoscalegroup.


```javascript
flatten|ec2Autoscale()
```

Returns: [Ec2AutoscaleNode](/kapacitor/v1.4/nodes/ec2_autoscale_node/)

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### Elapsed

Compute the elapsed time between points


```javascript
flatten|elapsed(field string, unit time.Duration)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Eval

Create an eval node that will evaluate the given transformation function to each data point.
A list of expressions may be provided and will be evaluated in the order they are given.
The results are available to later expressions.


```javascript
flatten|eval(expressions ...ast.LambdaNode)
```

Returns: [EvalNode](/kapacitor/v1.4/nodes/eval_node/)

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### First

Select the first point.


```javascript
flatten|first(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Flatten

Flatten points with similar times into a single point.


```javascript
flatten|flatten()
```

Returns: [FlattenNode](/kapacitor/v1.4/nodes/flatten_node/)

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### GroupBy

Group the data by a set of tags.

Can pass literal * to group by all dimensions.
Example:


```javascript
    |groupBy(*)
```



```javascript
flatten|groupBy(tag ...interface{})
```

Returns: [GroupByNode](/kapacitor/v1.4/nodes/group_by_node/)

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### HoltWinters

Compute the holt-winters (/{{< latest "influxdb" "v1" >}}/query_language/functions/#holt-winters) forecast of a data set.


```javascript
flatten|holtWinters(field string, h int64, m int64, interval time.Duration)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### HoltWintersWithFit

Compute the holt-winters (/{{< latest "influxdb" "v1" >}}/query_language/functions/#holt-winters) forecast of a data set.
This method also outputs all the points used to fit the data in addition to the forecasted data.


```javascript
flatten|holtWintersWithFit(field string, h int64, m int64, interval time.Duration)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### HttpOut

Create an HTTP output node that caches the most recent data it has received.
The cached data is available at the given endpoint.
The endpoint is the relative path from the API endpoint of the running task.
For example, if the task endpoint is at `/kapacitor/v1/tasks/<task_id>` and endpoint is
`top10`, then the data can be requested from `/kapacitor/v1/tasks/<task_id>/top10`.


```javascript
flatten|httpOut(endpoint string)
```

Returns: [HTTPOutNode](/kapacitor/v1.4/nodes/http_out_node/)

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### HttpPost

Creates an HTTP Post node that POSTS received data to the provided HTTP endpoint.
HttpPost expects 0 or 1 arguments. If 0 arguments are provided, you must specify an
endpoint property method.


```javascript
flatten|httpPost(url ...string)
```

Returns: [HTTPPostNode](/kapacitor/v1.4/nodes/http_post_node/)

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### InfluxDBOut

Create an influxdb output node that will store the incoming data into InfluxDB.


```javascript
flatten|influxDBOut()
```

Returns: [InfluxDBOutNode](/kapacitor/v1.4/nodes/influx_d_b_out_node/)

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### Join

Join this node with other nodes. The data is joined on timestamp.


```javascript
flatten|join(others ...Node)
```

Returns: [JoinNode](/kapacitor/v1.4/nodes/join_node/)

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### K8sAutoscale

Create a node that can trigger autoscale events for a kubernetes cluster.


```javascript
flatten|k8sAutoscale()
```

Returns: [K8sAutoscaleNode](/kapacitor/v1.4/nodes/k8s_autoscale_node/)

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### KapacitorLoopback

Create an kapacitor loopback node that will send data back into Kapacitor as a stream.


```javascript
flatten|kapacitorLoopback()
```

Returns: [KapacitorLoopbackNode](/kapacitor/v1.4/nodes/kapacitor_loopback_node/)

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### Last

Select the last point.


```javascript
flatten|last(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Log

Create a node that logs all data it receives.


```javascript
flatten|log()
```

Returns: [LogNode](/kapacitor/v1.4/nodes/log_node/)

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### Max

Select the maximum point.


```javascript
flatten|max(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Mean

Compute the mean of the data.


```javascript
flatten|mean(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Median

Compute the median of the data. Note, this method is not a selector,
if you want the median point use `.percentile(field, 50.0)`.


```javascript
flatten|median(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Min

Select the minimum point.


```javascript
flatten|min(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Mode

Compute the mode of the data.


```javascript
flatten|mode(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### MovingAverage

Compute a moving average of the last window points.
No points are emitted until the window is full.


```javascript
flatten|movingAverage(field string, window int64)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Percentile

Select a point at the given percentile. This is a selector function, no interpolation between points is performed.


```javascript
flatten|percentile(field string, percentile float64)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Sample

Create a new node that samples the incoming points or batches.

One point will be emitted every count or duration specified.


```javascript
flatten|sample(rate interface{})
```

Returns: [SampleNode](/kapacitor/v1.4/nodes/sample_node/)

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### Shift

Create a new node that shifts the incoming points or batches in time.


```javascript
flatten|shift(shift time.Duration)
```

Returns: [ShiftNode](/kapacitor/v1.4/nodes/shift_node/)

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### Sideload

Create a node that can load data from external sources


```javascript
flatten|sideload()
```

Returns: [SideloadNode](/kapacitor/v1.4/nodes/sideload_node/)

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### Spread

Compute the difference between `min` and `max` points.


```javascript
flatten|spread(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### StateCount

Create a node that tracks number of consecutive points in a given state.


```javascript
flatten|stateCount(expression ast.LambdaNode)
```

Returns: [StateCountNode](/kapacitor/v1.4/nodes/state_count_node/)

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### StateDuration

Create a node that tracks duration in a given state.


```javascript
flatten|stateDuration(expression ast.LambdaNode)
```

Returns: [StateDurationNode](/kapacitor/v1.4/nodes/state_duration_node/)

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### Stats

Create a new stream of data that contains the internal statistics of the node.
The interval represents how often to emit the statistics based on real time.
This means the interval time is independent of the times of the data points the source node is receiving.


```javascript
flatten|stats(interval time.Duration)
```

Returns: [StatsNode](/kapacitor/v1.4/nodes/stats_node/)

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### Stddev

Compute the standard deviation.


```javascript
flatten|stddev(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Sum

Compute the sum of all values.


```javascript
flatten|sum(field string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### SwarmAutoscale

Create a node that can trigger autoscale events for a docker swarm cluster.


```javascript
flatten|swarmAutoscale()
```

Returns: [SwarmAutoscaleNode](/kapacitor/v1.4/nodes/swarm_autoscale_node/)

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### Top

Select the top `num` points for `field` and sort by any extra tags or fields.


```javascript
flatten|top(num int64, field string, fieldsAndTags ...string)
```

Returns: [InfluxQLNode](/kapacitor/v1.4/nodes/influx_q_l_node/)

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### Union

Perform the union of this node and all other given nodes.


```javascript
flatten|union(node ...Node)
```

Returns: [UnionNode](/kapacitor/v1.4/nodes/union_node/)

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### Where

Create a new node that filters the data stream by a given expression.


```javascript
flatten|where(expression ast.LambdaNode)
```

Returns: [WhereNode](/kapacitor/v1.4/nodes/where_node/)

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### Window

Create a new node that windows the stream by time.

NOTE: Window can only be applied to stream edges.


```javascript
flatten|window()
```

Returns: [WindowNode](/kapacitor/v1.4/nodes/window_node/)

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