docs-v2/content/flux/v0/stdlib/universe/set.md

title	description	menu	weight	flux/v0/tags	introduced
set() function	`set()` assigns a static column value to each row in the input tables.	flux_v0_ref name parent identifier set universe universe/set	101	transformations	0.7.0

set() assigns a static column value to each row in the input tables.

set() may modify an existing column or add a new column. If the modified column is part of the group key, output tables are regrouped as needed. set() can only set string values.

Function type signature

(<-tables: stream[A], key: string, value: string) => stream[A] where A: Record

{{% caption %}} For more information, see Function type signatures. {{% /caption %}}

Parameters

key

({{< req >}}) Label of the column to modify or set.

value

({{< req >}}) String value to set.

tables

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

Examples

Set a column to a specific string value

import "sampledata"

sampledata.int()
    |> set(key: "host", value: "prod1")

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

Input data

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

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

Output data

_time	_value	*tag	host
2021-01-01T00:00:00Z	-2	t1	prod1
2021-01-01T00:00:10Z	10	t1	prod1
2021-01-01T00:00:20Z	7	t1	prod1
2021-01-01T00:00:30Z	17	t1	prod1
2021-01-01T00:00:40Z	15	t1	prod1
2021-01-01T00:00:50Z	4	t1	prod1

_time	_value	*tag	host
2021-01-01T00:00:00Z	19	t2	prod1
2021-01-01T00:00:10Z	4	t2	prod1
2021-01-01T00:00:20Z	-3	t2	prod1
2021-01-01T00:00:30Z	19	t2	prod1
2021-01-01T00:00:40Z	13	t2	prod1
2021-01-01T00:00:50Z	1	t2	prod1

{{% /expand %}} {{< /expand-wrapper >}}