findColumn() function

findColumn() returns an array of values in a specified column from the first table in a stream of tables that matches the specified predicate function.

The function returns an empty array if no table is found or if the column label is not present in the set of columns.

Function type signature
(<-tables: stream[B], column: string, fn: (key: A) => bool) => [C] where A: Record, B: Record
For more information, see Function type signatures.



(Required) Column to extract.


(Required) Predicate function to evaluate input table group keys.

findColumn() uses the first table that resolves as true. The predicate function requires a key argument that represents each input table’s group key as a record.


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


Extract a column as an array

import "sampledata"
    |> findColumn(fn: (key) => key.tag == "t1", column: "_value")// Returns [-2, 10, 7, 17, 15, 4]

Was this page helpful?

Thank you for your feedback!

Linux Package Signing Key Rotation

All signed InfluxData Linux packages have been resigned with an updated key. If using Linux, you may need to update your package configuration to continue to download and verify InfluxData software packages.

For more information, see the Linux Package Signing Key Rotation blog post.

State of the InfluxDB Cloud (IOx) documentation

The new documentation for InfluxDB Cloud backed by InfluxDB IOx is a work in progress. We are adding new information and content almost daily. Thank you for your patience!

If there is specific information you’re looking for, please submit a documentation issue.