docs-v2/content/enterprise_influxdb/v1/flux/guides/first-last.md

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---
title: Query first and last values
seotitle: Query first and last values in Flux
list_title: First and last
description: >
Use the `first()` or `last()` functions to return the first or last point in an input table.
weight: 10
menu:
enterprise_influxdb_v1:
parent: Query with Flux
name: First & last
list_query_example: first_last
canonical: /influxdb/v2/query-data/flux/first-last/
v2: /influxdb/v2/query-data/flux/first-last/
---
Use the [`first()`](/flux/v0/stdlib/universe/first/) or
[`last()`](/flux/v0/stdlib/universe/last/) functions
to return the first or last record in an input table.
```js
data
|> first()
// OR
data
|> last()
```
{{% note %}}
By default, InfluxDB returns results sorted by time, however you can use the
[`sort()` function](/flux/v0/stdlib/universe/sort/)
to change how results are sorted.
`first()` and `last()` respect the sort order of input data and return records
based on the order they are received in.
{{% /note %}}
### first
`first()` returns the first non-null record in an input table.
{{< flex >}}
{{% flex-content %}}
**Given the following input:**
| _time | _value |
|:----- | ------:|
| 2020-01-01T00:01:00Z | 1.0 |
| 2020-01-01T00:02:00Z | 1.0 |
| 2020-01-01T00:03:00Z | 2.0 |
| 2020-01-01T00:04:00Z | 3.0 |
{{% /flex-content %}}
{{% flex-content %}}
**The following function returns:**
```js
|> first()
```
| _time | _value |
|:----- | ------:|
| 2020-01-01T00:01:00Z | 1.0 |
{{% /flex-content %}}
{{< /flex >}}
### last
`last()` returns the last non-null record in an input table.
{{< flex >}}
{{% flex-content %}}
**Given the following input:**
| _time | _value |
|:----- | ------:|
| 2020-01-01T00:01:00Z | 1.0 |
| 2020-01-01T00:02:00Z | 1.0 |
| 2020-01-01T00:03:00Z | 2.0 |
| 2020-01-01T00:04:00Z | 3.0 |
{{% /flex-content %}}
{{% flex-content %}}
**The following function returns:**
```js
|> last()
```
| _time | _value |
|:----- | ------:|
| 2020-01-01T00:04:00Z | 3.0 |
{{% /flex-content %}}
{{< /flex >}}
## Use first() or last() with aggregateWindow()
Use `first()` and `last()` with [`aggregateWindow()`](/flux/v0/stdlib/universe/aggregatewindow/)
to select the first or last records in time-based groups.
`aggregateWindow()` segments data into windows of time, aggregates data in each window into a single
point using aggregate or selector functions, and then removes the time-based segmentation.
{{< flex >}}
{{% flex-content %}}
**Given the following input:**
| _time | _value |
|:----- | ------:|
| 2020-01-01T00:00:00Z | 10 |
| 2020-01-01T00:00:15Z | 12 |
| 2020-01-01T00:00:45Z | 9 |
| 2020-01-01T00:01:05Z | 9 |
| 2020-01-01T00:01:10Z | 15 |
| 2020-01-01T00:02:30Z | 11 |
{{% /flex-content %}}
{{% flex-content %}}
**The following function returns:**
{{< code-tabs-wrapper >}}
{{% code-tabs %}}
[first](#)
[last](#)
{{% /code-tabs %}}
{{% code-tab-content %}}
```js
|> aggregateWindow(
every: 1h,
fn: first,
)
```
| _time | _value |
|:----- | ------:|
| 2020-01-01T00:00:59Z | 10 |
| 2020-01-01T00:01:59Z | 9 |
| 2020-01-01T00:02:59Z | 11 |
{{% /code-tab-content %}}
{{% code-tab-content %}}
```js
|> aggregateWindow(
every: 1h,
fn: last,
)
```
| _time | _value |
|:----- | ------:|
| 2020-01-01T00:00:59Z | 9 |
| 2020-01-01T00:01:59Z | 15 |
| 2020-01-01T00:02:59Z | 11 |
{{% /code-tab-content %}}
{{< /code-tabs-wrapper >}}
{{%/flex-content %}}
{{< /flex >}}