Upsert Row by Key - DE Key
PUT https://{{et_subdomain}}.rest.marketingcloudapis.com/hub/v1/dataeventsasync/key:{DE_External_Key}/rows/Email:example@example.com
Upserts a data extension row by primary key using Data Extension's External Key.
Request Body
{"values"=>{"LastLogin"=>"2013-05-23T14:32:00Z", "IsActive"=>true, "FirstName"=>"John", "FollowerCount"=>2, "LastName"=>"Smith"}}