---
title: "Send additional guest data"
slug: "send-additional-guest-data"
abstract: "Overview of sending additional guest data to Sitecore CDP using the Batch API."
---
# Send additional guest data

::::tabs
:::tab{title="2.1"}

A guest data extension is an array that enables you to specify whatever name/value pairs (attributes) you want. Guest data extensions are optional and enable your organization to capture more robust information about your guests.

The [guest extension data model](https://doc.sitecore.com/cdp/en/developers/api/batch-api/batch-api-guest/guest-extension-data-model.html "Guest extension data model") is linked to a guest object that enables you to extend your own requirements and custom attributes onto the guest object. You can insert one data extension within the array.

The following is a list of guidelines for using the guest data extension:

- Place the data extension data in the `extensions` array of objects.
- The `name` attribute must be `ext`. Or, if you are sending guest extension data from multiple sources, it must be `ext1`, `ext2`, `ext3`, `ext4` or `ext5`.
- The `key` attribute must be `default`.
- A guest data extension has a maximum of 100 attributes.

The following is a list of guidelines for using attributes in the data extension:

- The attribute name must be alphanumeric \[A-Z,a-z,0-9\] as per the [JSON RFC 7159](https://www.rfc-editor.org/rfc/rfc7159) specification.
- You must write the attribute name of the data extension in camel case.
- The attribute name must be unique across all guest data extension groups.
- We recommend making the attribute name meaningful.

sidebar. Sending guest extension data from multiple source systems

Your organization can send guest extension data from multiple source systems to Sitecore CDP. You can include a maximum 100 custom attributes in each guest data extension group.

For example, your organization might want to send guest data extensions from a loyalty system to capture loyalty data and a Customer Relationship Management (CRM) system to capture email preferences, alternative mailing addresses, and so on.

> [!warning]
> To send data from multiple source systems, you must use a different extension group name for each source system. If you do not do this, each time a source system sends guest extension data to Sitecore CDP, it will overwrite guest extension data sent from other source systems.

Your organization can use a maximum of six guest data extension groups. Each group name represents a different source system. You must use the extension group names as follows:

- `ext`
- `ext1`
- `ext2`
- `ext3`
- `ext4`
- `ext5`

You must specify the guest data extension group in the name attribute.

For example, if you want to send data from a loyalty system to Sitecore CDP, your organization must always use the same guest extension group name as the value in the key-value pair. Do not use the same guest extension group name to send extensions from other source systems.

> [!note]
> Use a consistent prefix in the key name of the key-value pair. This helps users quickly find all guest data extensions from a particular source system in the batch segmentation UI. For example, if you use `member` as a prefix, all `member` guest data extensions display together in the UI in alphabetical order. This also ensures that you do not overwrite key-value pairs sent from other source systems. For example, a key with `number` might exist for a loyalty membership and CRM system.

sidebar. Accessing guest data extensions in batch segmentation

Users can access guest data extensions in batch segmentation, as shown in the following example:

![Accessing guest data extensions in batch segmentation](https://doc.sitecore.com/api/markdown-image/cdp/en/developers/api/images/guestDataExt.png)

In this example, `memberCardBalance`, `memberCardCategory`, and `memberCardType`, become guest data extensions sent from your orgnaization's loyalty system:

```json
{
   "ref":"9d94ee11-7043-4b71-980c-a777d00a7b46",
   "schema":"guest",
   "mode":"upsert",
   "value":{
      "guestType":"customer",
      "firstSeen":"2010-03-07T16:`15:11`.000Z",
      "lastSeen":"2012-08-23T16:`17:16`.000Z",
      "identifiers":[
         {
            "provider":"IDENTITY_SYSTEM",
            "id":"B7524AE6-CF1C-440F-B1A2-0C9D42F5CB41",
            "expiryDate":"2016-08-23T16:`17:16`.000Z"
         }
      ],
      "extensions":[
         {
            "name":"ext",
            "key":"default",
            "memberCardBalance": 5012.25,
            "memberCardType":"vip",
            "memberCardType":"platinum"
         }
      ]
   }
}

```

:::
:::tab{title="2.0"}

2.0 data model does not support this functionality.

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