title: BigQuery Dataset/Table expiration by Policy
body: <p>I'm trying to figure out if I can create multiple service accounts and for each service account create a different Policy (or even a generic policy).
  In this policy I want to set the default retention for a dataset/table.
  Only I (admin) can change the retention after table creation.</p>
  
  <p>This is very important to control costs.</p>
  
  <p>Did anyone managed to do this?</p>