A field called
_id appears in the table that Webhooks are written to. This was not sent as part of the event payload. Where does it come from?
_id field is generated by Google Pub/Sub which Fivetran uses to manage topic subscriptions.
This is an id that is guaranteed to be unique within a topic. In the context of Fivetran, a topic will often correlate to the Webhook endpoint in your Webhook connector. Google's definition of that ID is shared below. Please find the documentation here, under
ID of this message, assigned by the server when the message is published. Guaranteed to be unique within the topic. This value may be read by a subscriber that receives a
Pullcall or a push delivery. It must not be populated by the publisher in a