> For the complete documentation index, see [llms.txt](https://docs.pentaho.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.pentaho.com/pdia-data-integration/9.3-data-integration/pdi-transformation-steps-reference-overview/elasticsearch-rest-bulk-insert/options-elasticsearch-rest-bulk-insert/document-tab-elasticsearch-rest-bulk-insert/using-an-existing-json-document-from-a-field-elasticsearch-rest-bulk-insert.md).

# Using an existing JSON document from a field

![Elasticsearch REST Bulk Insert step, Document tab - Use existing option](/files/OoEHpnm7qWZZffqXu0Qx)

Choose the **Use an existing JSON document from a field** option if the document that you want to index is already in a JSON form in a field on the input stream.

| Field          | Description                                                                                              |
| -------------- | -------------------------------------------------------------------------------------------------------- |
| **JSON Field** | Select the name of the incoming field that contains a JSON document to be indexed for each row of input. |


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