# Guest data extension

A guest data extension is an object that lets you specify any key-value pairs you want. Guest data extensions are optional and enable your organization to capture more robust information about your guests.

 To get started with this API, create a data extension for the guest you previously created, then find the data in Sitecore CDP in the guest profile.

 - [POST /v2.1/guests/{guestRef}/extensions](https://api-docs.sitecore.com/cdp/guest-rest-api/guest-data-extension/createguestdataextension.md): Creates a data extension for a guest. You can create up to six data extensions. To avoid creating key-value pairs in a data extension that already exist within a guest profile, first retrieve a guest'
 - [GET /v2.1/guests/{guestRef}/extensions](https://api-docs.sitecore.com/cdp/guest-rest-api/guest-data-extension/retrieveguestdataextensions.md): Retrieves the URLs for each of the guest's data extensions. We recommend that you retrieve the URLs using the `expand=true` query parameter to check that the keys you intend to create when you Create
 - [GET /v2.1/guests/{guestRef}/extensions/{dataExtensionName}](https://api-docs.sitecore.com/cdp/guest-rest-api/guest-data-extension/retrieveguestdataextension.md): Retrieves a data extension for a guest.
 - [PUT /v2.1/guests/{guestRef}/extensions/{dataExtensionName}](https://api-docs.sitecore.com/cdp/guest-rest-api/guest-data-extension/putguestdataextension.md): Fully updates a data extension for a guest, replacing the entire resource including all the key-value pairs with the data you send in the request. To update certain key-value pairs only, use the Part
 - [PATCH /v2.1/guests/{guestRef}/extensions/{dataExtensionName}](https://api-docs.sitecore.com/cdp/guest-rest-api/guest-data-extension/updateguestdataextension.md): Partially updates a data extension for a guest, replacing only those key-value pairs in the resource that you provide in the request. If multiple source systems use the same data extension, use this
 - [DELETE /v2.1/guests/{guestRef}/extensions/{dataExtensionName}](https://api-docs.sitecore.com/cdp/guest-rest-api/guest-data-extension/deleteguestdataextension.md): Deletes the data extension for a guest, including all the key-value pairs in the data extension. To delete certain key-value pairs only, use the Delete key-value pairs from a data extension endpoint
 - [DELETE /v2.1/guests/{guestRef}/extensions/{dataExtensionName}/fields](https://api-docs.sitecore.com/cdp/guest-rest-api/guest-data-extension/deleteguestdataextensionfields.md): Deletes the key-value pairs you provide in the `name` query parameter from a data extension for a guest. For example, if your data extension contains the `vipMember` and `loyaltyMember` keys, you can