> Portal Navigation:
> 
> - Append `.md` to any URL under `https://dev.wix.com/docs/` to get its markdown version.
> - Pages are either content pages (article or reference text) or menu pages (a list of links to child pages).
> - To get a menu page, truncate any URL to a parent path and append `.md` (e.g. `https://dev.wix.com/docs/sdk.md`, `https://dev.wix.com/docs/sdk/core-modules.md`).
> - Top-level index of all portals: https://dev.wix.com/docs/llms.txt
> - Full concatenated docs: https://dev.wix.com/docs/llms-full.txt

## Resource: Sample Flows

## Article: Sample Flows

## Article Link: https://dev.wix.com/docs/api-reference/business-management/data-extension-schema/sample-flows.md

## Article Content:

# Sample Flows

This article shares some possible use cases you could support, as well as an example flow that could support each use case. 
You're certainly not limited to these use cases, but they can be a helpful jumping off point as you plan your implementation.

## Retrieve a list of all data extension schemas for the Wix eCommerce Checkout object 
If your functionality requires access to fields that have been added to an object, you might want to retrieve all of the schemas at once. For example, displaying the returned fields to site visitors. 

1. Collect the FQDN of the relevant Wix API service object that [supports schema plugin extensions](https://dev.wix.com/docs/build-apps/develop-your-app/extensions/backend-extensions/schema-plugins/about-schema-plugin-extensions.md#see-also). FQDNs are also returned as `entityFqdn` in most events. The Wix eCommerce Checkout FQDN is `wix.ecom.*.checkout`.
   > **Note:** Use a wildcard (*) in place of the FQDN's version number to ensure your code will continue to work when Wix updates the service object to a newer version.
2. Choose the namespaces you would like to retrieve the data for. You can pass multiple namespaces in one call, or leave it blank to retrieve all available namespaces.
3. Call [List Data Extension Schemas](https://dev.wix.com/docs/rest/business-management/data-extension-schema/list-data-extension-schemas.md) with the FQDN, namespace data, and fields set to `"ARCHIVED"`. This ensures that any archived fields are returned and provides a complete schema.
4. Display the returned data as relevant.


## Add a field to a user-defined data extension schema for the Wix eCommerce Order object
Display a site-specific field, such as alcohol by volume (ABV) for whiskey orders, alongside fields from Wix eCommerce Orders, to site visitors.

1.  Collect the FQDN of the relevant Wix API object that [supports schema plugin extensions](https://dev.wix.com/docs/build-apps/develop-your-app/extensions/backend-extensions/schema-plugins/about-schema-plugin-extensions.md#see-also). FQDNs are also returned as `entityFqdn` in most events. The Wix eCommerce Order FQDN is `wix.ecom.*.order`.   
    > **Note:** Use a wildcard (*) in place of the FQDN's version number to ensure your code will continue to work when Wix updates the service object to a newer version.
2. Call [List Data Extension Schemas](https://dev.wix.com/docs/rest/business-management/data-extension-schema/list-data-extension-schemas.md) with the `wix.ecom.*.order` FQDN and `_user_fields` namespace to check if a user-defined schema exists.
3. Create or update the `_user_fields` namespace, as relevant:
    + If no `_user_fields` namespace schema exists, call [Create Data Extension Schema](https://dev.wix.com/docs/rest/business-management/data-extension-schema/create-data-extension-schema.md) with the `wix.ecom.*.order` FQDN, the `_user_fields` namespace and the new JSON schema.
    + If a `_user_fields` namespace schema already exists, call [Update Data Extension Schema](https://dev.wix.com/docs/rest/business-management/data-extension-schema/update-data-extension-schema.md) with the `wix.ecom.*.order` FQDN, the `_user_fields` namespace and the updated JSON schema.  Make sure to specify the entire schema, as any field not specified will be deleted.
4. Display the user-defined field as relevant.

> **Note**: Once you've added a user-defined field to the site's schema, you should call the relevant GET call for the target API object - in this case, [Get Order](https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/orders/orders/get-order.md) - every time a visitor navigates to your UI to collect and display the user fields.