Is it possible to set up dbt so that you build models directly off instances in CloudSQL?
Or do you need to create an external table in BigQuery with a connection to CloudSQL first as a federate query?
I have not seen examples of the former being done so I assume it's not possible because of the storage and application differences but want to confirm with smarter people out there.
You can use dbt to build models directly with CloudSQL. Currently dbt has a verified adapter for Postgres and community adapters for MySQL and SQL Server.
More info: https://docs.getdbt.com/docs/supported-data-platforms