Drivetrain supports integration with BigQuery from a read-only external user account. To get started you would need to share the read-only access with [email protected] service account.
Add an external user in BigQuery
To grant an access to external user, (someone who is not listed as an employee in the company), follow these steps:
Select the Dataset/ Resource which is to be shared with the user.
From the Sharing option on the right top of the page, route to Permissions.