Looking through the Bulk Extract API documentation, I think the marketoGUID represents the UID for that particular object? So, for example, if exporting the Activity "Clicks Link in Email," the marketoGUID would stand for the unique identifier for that Activity and really represents a "moment in time". This is also then the field which we would want to dedupe. Also, if that's correct, then I think the marketoGUID should not be related to across different activities? So, for example, if user X opened and clicked an email, then the marketoGUID in the click activity record and the marketoGUID in the open activity record for that user would be different and thus not relatable.
Am I understanding it correctly? Any insight would be appreciated.