---
title: stack es transform preview-transform cli command
description: Preview a transform. Behaviour flags: --dry-run — validate all inputs and exit without performing any action 
url: https://www.elastic.co/elastic/docs-builder/docs/4089/reference/elastic-cli/cli/stack/es/transform/preview-transform
applies_to:
  - Elastic Cloud Serverless: Preview
  - Elastic Stack: Preview
---

# stack es transform preview-transform cli command
<cli-modifiers>
</cli-modifiers>

```bash
elastic stack es transform preview-transform [options]
```

Preview a transform.
**Behaviour flags:**
`--dry-run` — validate all inputs and exit without performing any action

## Options

<definitions>
  <definition term="--timeout string">
    Period to wait for a response. If no response is received before the
    timeout expires, the request fails and returns an error.
  </definition>
  <definition term="--dest string">
    The destination for the transform.
  </definition>
  <definition term="--description string">
    Free text description of the transform.
  </definition>
  <definition term="--frequency string">
    The interval between checks for changes in the source indices when the
    transform is running continuously. Also determines the retry interval in
    the event of transient failures while the transform is searching or
    indexing. The minimum value is 1s and the maximum is 1h.
  </definition>
  <definition term="--pivot string">
    The pivot method transforms the data by aggregating and grouping it.
    These objects define the group by fields and the aggregation to reduce
    the data.
  </definition>
  <definition term="--source string">
    The source of the data for the transform.
  </definition>
  <definition term="--settings string">
    Defines optional transform settings.
  </definition>
  <definition term="--sync string">
    Defines the properties transforms require to run continuously.
  </definition>
  <definition term="--retention-policy string">
    Defines a retention policy for the transform. Data that meets the defined
    criteria is deleted from the destination index.
  </definition>
  <definition term="--latest string">
    The latest method transforms the data by finding the latest document for
    each unique key.
  </definition>
  <definition term="--transform-id string">
    Identifier for the transform to preview. If you specify this path parameter, you cannot provide transform
    configuration details in the request body.
  </definition>
  <definition term="--error-trace">
    When set to `true` Elasticsearch will include the full stack trace of errors
    when they occur.
  </definition>
  <definition term="--filter-path string">
    Comma-separated list of filters in dot notation which reduce the response
    returned by Elasticsearch.
    **Repeatable:** pass `--filter-path` multiple times to supply more than one value
  </definition>
  <definition term="--human">
    When set to `true` will return statistics in a format suitable for humans.
    For example `"exists_time": "1h"` for humans and
    `"exists_time_in_millis": 3600000` for computers. When disabled the human
    readable values will be omitted. This makes sense for responses being consumed
    only by machines.
  </definition>
  <definition term="--pretty">
    If set to `true` the returned JSON will be "pretty-formatted". Only use
    this option for debugging only.
  </definition>
  <definition term="--input-file string">
    path to a JSON file to use as command input
  </definition>
  <definition term="--dry-run">
    validate all inputs and exit without performing any action (preview changes without applying them)
  </definition>
</definitions>


## Global Options

<definitions>
  <definition term="--json">
    output as JSON
  </definition>
</definitions>