code: @BetaApi(
        "The surface for long-running operations is not stable yet and may change in the future.")
    public final OperationFuture<Database, CreateDatabaseMetadata> createDatabaseAsync(
        InstanceName parent, String createStatement) {
  
      CreateDatabaseRequest request =
          CreateDatabaseRequest.newBuilder()
              .setParent(parent == null ? null : parent.toString())
              .setCreateStatement(createStatement)
              .build();
      return createDatabaseAsync(request);
    }
docs: Creates a new Cloud Spanner database and starts to prepare it for serving. The returned
  [long-running operation][google.longrunning.Operation] will have a name of the format
  `&lt;database_name&gt;/operations/&lt;operation_id&gt;` and can be used to track preparation of
  the database. The [metadata][google.longrunning.Operation.metadata] field type is
  [CreateDatabaseMetadata][google.spanner.admin.database.v1.CreateDatabaseMetadata]. The
  [response][google.longrunning.Operation.response] field type is
  [Database][google.spanner.admin.database.v1.Database], if successful.
  
  <p>Sample code:
  
  <pre><code>
  try (DatabaseAdminClient databaseAdminClient = DatabaseAdminClient.create()) {
  InstanceName parent = InstanceName.of("[PROJECT]", "[INSTANCE]");
  String createStatement = "";
  Database response = databaseAdminClient.createDatabaseAsync(parent, createStatement).get();
  }
  </code></pre>
  
  @param parent Required. The name of the instance that will serve the new database. Values are
  of the form `projects/&lt;project&gt;/instances/&lt;instance&gt;`.
  @param createStatement Required. A `CREATE DATABASE` statement, which specifies the ID of the
  new database. The database ID must conform to the regular expression
  `[a-z][a-z0-9_\-]&#42;[a-z0-9]` and be between 2 and 30 characters in length. If the
  database ID is a reserved word or if it contains a hyphen, the database ID must be enclosed
  in backticks (`` ` ``).
  @throws com.google.api.gax.rpc.ApiException if the remote call fails