text: -- Start transaction and plan the tests.
  BEGIN;
  SELECT plan(6);
  
  -- Run the tests.
  SELECT col_is_pk('contract_notifications', 'id');
  SELECT col_is_pk('contracts', 'id');
  SELECT col_is_pk('files', 'id');
  SELECT col_is_pk('rank_history', 'id');
  SELECT col_is_pk('roles', 'id');
  SELECT col_is_pk('users', 'id');
  
  -- Finish the tests and clean up.
  SELECT * FROM finish();
  ROLLBACK;