---
title: "Differences between v2 and v2.1 of the Guest and Guest data extension REST APIs"
slug: "differences-between-v2-and-v2-1-of-the-guest-and-guest-data-extension-rest-apis"
abstract: "Find out what's changed in version 2.1 of the Sitecore CDP Guest and the Guest data extension REST APIs, so you can upgrade."
---
# Differences between v2 and v2.1 of the Guest and Guest data extension REST APIs

If your instance of Sitecore CDP is using the [2.1 data model](https://doc.sitecore.com/cdp/en/developers/api/rest-apis/legacy-rest-apis/guest-rest-api-v2--legacy-/index-en.html#UUID-fa0730dc-dcdf-341a-4167-ecbe18758626 "Data models"), we recommend that you upgrade to the Guest and Guest data extension REST APIs version 2.1.

Here's an overview of the main differences between version 2 and version 2.1:

|  | v2 | v2.1 |
| --- | --- | --- |
| URI paths | URI paths contain `/v2/`. | URI paths contain `/v2.1/`. |
| Endpoints for partial operations | <ul><li>Partial updates and partial deletions are not available.</li><li>Updates and deletions affect the entire resource. Because of this, you must use a different data extension name for each source system so that updates from one source system do not overwrite the data from a different source system.</li></ul> | <ul><li>New `PATCH` endpoints let you [partially update guests](https://doc.sitecore.com/cdp/en/developers/guest-rest-api/index.html#tag/Guest/operation/UpdateGuests) and [partially update data extensions](https://doc.sitecore.com/cdp/en/developers/guest-rest-api/index.html#tag/Guest-data-extension/operation/UpdateGuestDataExtension). For example, you can update certain key-value pairs without affecting others.</li><li>A new `DELETE` endpoint lets you [delete certain key-value pairs from a guest data extension](https://doc.sitecore.com/cdp/en/developers/guest-rest-api/index.html#tag/Guest-data-extension/operation/deleteGuestDataExtensionFields) without affecting others.</li><li>With partial operations, you no longer have to use a different data extension name for each source system, but we still recommend it as a best practice.</li></ul> |
| Endpoints for data extensions | Endpoints for data extensions use the less developer-friendly data extension reference. | More developer-friendly data extension endpoints let you specify the name of the data extension ([see the possible values](https://doc.sitecore.com/cdp/en/developers/guest-rest-api/index.html#tag/Guest-data-extension/operation/CreateGuestDataExtension)) in the request body when you create a data extension. You can then use that name in the URI of other endpoints to work with the data extension. |