docs-v2/content/flux/v0/stdlib/experimental/preview.md

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---
title: experimental.preview() function
description: >
`experimental.preview()` limits the number of rows and tables in the stream.
menu:
flux_v0_ref:
name: experimental.preview
parent: experimental
identifier: experimental/preview
weight: 101
flux/v0/tags: [transformations]
introduced: 0.167.0
---
<!------------------------------------------------------------------------------
IMPORTANT: This page was generated from comments in the Flux source code. Any
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To make updates to this documentation, update the function comments above the
function definition in the Flux source code:
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Contributing to Flux: https://github.com/influxdata/flux#contributing
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------------------------------------------------------------------------------->
`experimental.preview()` limits the number of rows and tables in the stream.
Included group keys are not deterministic and depends on the order
that the engine sends them.
##### Function type signature
```js
(<-tables: stream[A], ?nrows: int, ?ntables: int) => stream[A] where A: Record
```
{{% caption %}}
For more information, see [Function type signatures](/flux/v0/function-type-signatures/).
{{% /caption %}}
## Parameters
### nrows
Maximum number of rows per table to return. Default is `5`.
### ntables
Maximum number of tables to return.
Default is `5`.
### tables
Input data. Default is piped-forward data (`<-`).
## Examples
### Preview data output
```js
import "experimental"
import "sampledata"
sampledata.int()
|> experimental.preview()
```