134 lines
3.4 KiB
Markdown
134 lines
3.4 KiB
Markdown
---
|
|
title: limit() function
|
|
description: >
|
|
`limit()` returns the first `n` rows after the specified `offset` from each input table.
|
|
menu:
|
|
flux_v0_ref:
|
|
name: limit
|
|
parent: universe
|
|
identifier: universe/limit
|
|
weight: 101
|
|
flux/v0/tags: [transformations, selectors]
|
|
introduced: 0.7.0
|
|
---
|
|
|
|
<!------------------------------------------------------------------------------
|
|
|
|
IMPORTANT: This page was generated from comments in the Flux source code. Any
|
|
edits made directly to this page will be overwritten the next time the
|
|
documentation is generated.
|
|
|
|
To make updates to this documentation, update the function comments above the
|
|
function definition in the Flux source code:
|
|
|
|
https://github.com/influxdata/flux/blob/master/stdlib/universe/universe.flux#L1674-L1674
|
|
|
|
Contributing to Flux: https://github.com/influxdata/flux#contributing
|
|
Fluxdoc syntax: https://github.com/influxdata/flux/blob/master/docs/fluxdoc.md
|
|
|
|
------------------------------------------------------------------------------->
|
|
|
|
`limit()` returns the first `n` rows after the specified `offset` from each input table.
|
|
|
|
If an input table has less than `offset + n` rows, `limit()` returns all rows
|
|
after the offset.
|
|
|
|
##### Function type signature
|
|
|
|
```js
|
|
(<-tables: stream[A], n: int, ?offset: int) => stream[A]
|
|
```
|
|
|
|
{{% caption %}}
|
|
For more information, see [Function type signatures](/flux/v0/function-type-signatures/).
|
|
{{% /caption %}}
|
|
|
|
## Parameters
|
|
|
|
### n
|
|
({{< req >}})
|
|
Maximum number of rows to return.
|
|
|
|
|
|
|
|
### offset
|
|
|
|
Number of rows to skip per table before limiting to `n`.
|
|
Default is `0`.
|
|
|
|
|
|
|
|
### tables
|
|
|
|
Input data. Default is piped-forward data (`<-`).
|
|
|
|
|
|
|
|
|
|
## Examples
|
|
|
|
- [Limit results to the first three rows in each table](#limit-results-to-the-first-three-rows-in-each-table)
|
|
- [Limit results to the first three rows in each input table after the first two](#limit-results-to-the-first-three-rows-in-each-input-table-after-the-first-two)
|
|
|
|
### Limit results to the first three rows in each table
|
|
|
|
```js
|
|
import "sampledata"
|
|
|
|
sampledata.int()
|
|
|> limit(n: 3)
|
|
|
|
```
|
|
|
|
{{< 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 |
|
|
| -------------------- | ------- | ---- |
|
|
| 2021-01-01T00:00:00Z | -2 | t1 |
|
|
| 2021-01-01T00:00:10Z | 10 | t1 |
|
|
| 2021-01-01T00:00:20Z | 7 | 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 |
|
|
|
|
{{% /expand %}}
|
|
{{< /expand-wrapper >}}
|
|
|
|
### Limit results to the first three rows in each input table after the first two
|
|
|
|
```js
|
|
import "sampledata"
|
|
|
|
sampledata.int()
|
|
|> limit(n: 3, offset: 2)
|
|
|
|
```
|
|
|