Upsert Row - DE Key

POST https://{{et_subdomain}}.rest.marketingcloudapis.com/hub/v1/dataeventsasync/key:{DE_External_Key}/rowset

https://developer.salesforce.com/docs/atlas.en-us.noversion.mc-apis.meta/mc-apis/postDataExtensionRowsetByKey.htm

The API upserts a single data extension row Asynchronously using Data Extension's External Key.

Request Body

{"0"=>{"keys"=>{"SubscriberKey"=>"5c68f5c7f2380288ba735091"}, "values"=>{"IsActive"=>true, "FirstName"=>"John", "LastName"=>"Smith", "LastLogin"=>"2018-05-23T14:32:00Z", "FollowerCount"=>2}}}