---
title: Add a runtime field to a data view from Discover
description: Add a runtime field to a data view from Discover when your data lacks a value you need, then use it in the table and in visualizations.
url: https://www.elastic.co/docs/explore-analyze/discover/add-fields-to-data-views
products:
  - Elastic Documentation
  - Kibana
applies_to:
  - Elastic Cloud Serverless: Generally available
  - Elastic Stack: Generally available
---

# Add a runtime field to a data view from Discover
When your data doesn't have a field you need, such as a value that is part of another field or a combination of two fields, you can add a [runtime field](https://www.elastic.co/docs/manage-data/data-store/mapping/runtime-fields), a field whose value Elasticsearch calculates from a script when you search, to your [data view](https://www.elastic.co/docs/explore-analyze/find-and-organize/data-views) without leaving **Discover**. You can then use the new field for analysis and visualizations the same way you use other fields.

## Before you begin

- Open **Discover** in classic mode, select the data view that you want to add the field to, and run a search so the fields list in the sidebar appears. If **Discover** opens in ES|QL mode, refer to [Switch to Discover's classic mode](/docs/explore-analyze/discover/switch-esql-mode#revert-to-classic-mode).
- Have a role with the **Data View Management** Kibana privilege and the `view_index_metadata` Elasticsearch privilege. Refer to [Defining roles](https://www.elastic.co/docs/deploy-manage/users-roles/cluster-or-deployment-auth/defining-roles).

<tip>
  In ES|QL mode, you don't need a runtime field. You can [calculate a field in the query](/docs/explore-analyze/discover/esql-results#esql-kibana-results-eval) instead.
</tip>


## Add a runtime field

1. Start from either location:
   - In the fields list in the sidebar, select **Add a field**.
   - In the data view menu, select **Add a field to this data view**.
2. Select the **Type** of value that the field holds:
   - **Keyword** for text, such as names or labels.
   - **Long** for whole numbers and **Double** for numbers with decimals.
   - **Date** for dates and times.
   - **IP** for IP addresses.
   - **Boolean** for true or false.
   - **Geo point** for locations.
   - **Composite** to produce several fields from one script. Refer to [Return multiple fields with a composite runtime field](/docs/explore-analyze/find-and-organize/data-views/runtime-fields#composite-runtime-field).
3. Enter a **Name** for the field. Use a name that follows the way the other fields of the data view are named. Changing the name or the type later can break searches and visualizations that use the field.
4. Turn on the options you need:
   - **Set custom label**: Show a label in place of the field name in Discover and other Kibana apps. This is useful for shortening a long field name. Queries and filters keep using the original field name.
   - **Set custom description**: Add a description that appears next to the field in Discover, Lens, and the Data Views management page.
   - **Set value**: Define a script that determines the value of the field, instead of retrieving it from the field with the same name in `_source`. The script must return a value of the **Type** you selected, or the data view fails wherever it's used. For Painless scripting language examples, refer to [Explore your data with runtime fields](https://www.elastic.co/docs/explore-analyze/find-and-organize/data-views/runtime-fields).
   - **Set format**: Set how the value is displayed. Changing the format can affect the value and prevent highlighting in Discover.
   - **Show advanced settings** → **Set popularity**: Adjust the popularity to make the field appear higher or lower in the fields list. By default, Discover orders fields from most selected to least selected.
5. To check what your script returns before you save, look at the **Preview**. Use the **Document ID** arrows to see the value for other documents.
6. Select **Save** to save your new field.

**Result:** The new field appears in the list of fields, and you can add it to the table. It's available wherever the data view is used. It doesn't change the index mapping in Elasticsearch, so your indexed data stays as it is.

## Examples

The following examples use the [sample ecommerce data](https://www.elastic.co/docs/manage-data/ingest/sample-data). The first adds a "Hello world" field. The second combines the `customer_first_name` and `customer_last_name` fields into a single "customer" field.

### Hello world field example

- **Name**: `hello`
- **Type**: `Keyword`
- **Set value**: Enabled
- **Script**:
  ```java
  emit("Hello World!");
  ```


### Customer field example

- **Name**: `customer`
- **Type**: `Keyword`
- **Set value**: Enabled
- **Script**:
  ```java
  String str = doc['customer_first_name.keyword'].value;
  char ch1 = str.charAt(0);
  emit(doc['customer_last_name.keyword'].value + ", " + ch1);
  ```


## Next steps

- To show the new field as a column, refer to [Explore fields in Discover](https://www.elastic.co/docs/explore-analyze/discover/explore-fields).
- To chart the new field, refer to [Visualize a field from Discover](https://www.elastic.co/docs/explore-analyze/discover/visualize-field).


## Related pages

- [How to query in Discover's classic mode](https://www.elastic.co/docs/explore-analyze/discover/use-classic-mode)
- [Explore your data with runtime fields](https://www.elastic.co/docs/explore-analyze/find-and-organize/data-views/runtime-fields)