title: How to specify fully identified database qualifier in Google Spanner
body: <p><a href="https://cloud.google.com/sdk/gcloud/reference/spanner/databases/execute-sql" rel="nofollow noreferrer">https://cloud.google.com/sdk/gcloud/reference/spanner/databases/execute-sql</a> says that the database positional parameter in an execute-sql command can be "ID of the database or fully qualified identifier for the database". </p>
  
  <p>I can't find the syntax for such a fully qualified identifier. Looked/searched anywhere I could think of in the documentation.</p>
  
  <p>Trying standard separators (slash, dot, colon, etc) produces random error messages. </p>
  
  <p>Any ideas?</p>