docs-v2/content/flux/v0.x/stdlib/universe/tail.md

title	description	aliases	menu	weight	flux/v0.x/tags	related	introduced
tail() function	The `tail()` function limits each output table to the last `n` records.	/influxdb/v2.0/reference/flux/functions/built-in/transformations/tail/ /influxdb/v2.0/reference/flux/stdlib/built-in/transformations/tail/ /influxdb/cloud/reference/flux/stdlib/built-in/transformations/tail/	flux_0_x_ref name parent tail universe	102	transformations	/flux/v0.x/stdlib/universe/limit/	0.39.0

The tail() function limits each output table to the last n records. The function produces one output table for each input table. Each output table contains the last n records before the offset. If the input table has less than offset + n records, tail() outputs all records before the offset.

tail(n: 10, offset: 0)

Parameters

n

({{< req >}}) The maximum number of records to output.

offset

The number of records to skip at the end of a table table before limiting to n. Default is 0.

tables

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

Examples

{{% flux/sample-example-intro %}}

• Output the last three rows in each input table
• Output the last three rows before the last row in each input table

Output the last three rows in each input table

import "sampledata"

sampledata.int()
    |> tail(n: 3)

{{< expand-wrapper >}} {{% expand "View input and output" %}} {{< flex >}} {{% flex-content %}}

Input data

{{% flux/sample "int" %}}

{{% /flex-content %}} {{% flex-content %}}

Output data

_time	tag	_value
2021-01-01T00:00:30Z	t1	17
2021-01-01T00:00:40Z	t1	15
2021-01-01T00:00:50Z	t1	4

_time	tag	_value
2021-01-01T00:00:30Z	t2	19
2021-01-01T00:00:40Z	t2	13
2021-01-01T00:00:50Z	t2	1
{{% /flex-content %}}
{{< /flex >}}
{{% /expand %}}
{{< /expand-wrapper >}}

Output the last three rows before the last row in each input table

import "sampledata"

sampledata.int()
    |> tail(n: 3, offset: 1)

{{< expand-wrapper >}} {{% expand "View input and output" %}} {{< flex >}} {{% flex-content %}}

Input data

{{% flux/sample "int" %}}

{{% /flex-content %}} {{% flex-content %}}

Output data

_time	tag	_value
2021-01-01T00:00:20Z	t1	7
2021-01-01T00:00:30Z	t1	17
2021-01-01T00:00:40Z	t1	15

_time	tag	_value
2021-01-01T00:00:20Z	t2	-3
2021-01-01T00:00:30Z	t2	19
2021-01-01T00:00:40Z	t2	13
{{% /flex-content %}}
{{< /flex >}}
{{% /expand %}}
{{< /expand-wrapper >}}