docs-v2/content/flux/v0.x/stdlib/experimental/first.md

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---
title: experimental.first() function
description: >
The `experimental.first()` function returns the first record with a non-null
value in the `_value` column.
menu:
flux_0_x_ref:
name: experimental.first
parent: experimental
weight: 302
aliases:
- /influxdb/v2.0/reference/flux/stdlib/experimental/first/
- /influxdb/cloud/reference/flux/stdlib/experimental/first/
related:
- /{{< latest "inflxudb" >}}/query-data/flux/first-last/
- /flux/v0.x/stdlib/universe/first/
- /{{< latest "influxdb" "v1" >}}/query_language/functions/#first, InfluxQL FIRST()
flux/v0.x/tags: [transformations, selectors]
introduced: 0.112.0
---
The `experimental.first()` function returns the first record with a non-null
value in the `_value` column.
_`experimental.first()` is a [selector function](/flux/v0.x/function-types/#selectors)._
```js
import "experimental"
experimental.first()
```
{{% warn %}}
#### Empty tables
`experimental.first()` drops empty tables.
{{% /warn %}}
## Parameters
### tables {data-type="stream of tables"}
Input data.
Default is piped-forward data (`<-`).
## Examples
#### Return the first non-null value
```js
import "experimental"
data
|> experimental.first()
```
{{< flex >}}
{{% flex-content %}}
##### Input data
| _time | _value |
|:----- | ------:|
| 2021-01-01T00:00:00Z | 1.2 |
| 2021-01-01T00:01:00Z | 0.6 |
| 2021-01-01T00:02:00Z | 2.3 |
| 2021-01-01T00:03:00Z | 0.9 |
{{% /flex-content %}}
{{% flex-content %}}
##### Output data
| _time | _value |
|:----- | ------:|
| 2021-01-01T00:00:00Z | 1.2 |
{{% /flex-content %}}
{{< /flex >}}