title: Airflow export all tables of a postgres DB to BigQuery
body: <p>I'm currently using Airflow <code>PostgresToGoogleCloudStorageOperator</code> and <code>GoogleCloudStorageToBigQueryOperator</code> to export every table of my Postgres DB (hosted on AWS RDS) to BigQuery. It works but I have 75 tables, so Airflow creates 75 * 2 jobs. Since I'm new to Airflow, I don't know if this is a good practice. </p>
  
  <p>In any case, I'd like to find a way to export all tables at once (pg_dump?) to GCS and then import them into BigQuery.</p>