anchor.diff:      ok = bdberl:close(?config(db, Config)),
       ok = bdberl:delete_database("api_test.db").
   
  -
   open_should_create_database_if_none_exists(Config) ->
       DbName = filename:join([?config(priv_dir, Config), "api_test.db"]),
       true = filelib:is_file(DbName).
  
positive.code: 
      {error, transaction_aborted} = bdberl:transaction(F),
      not_found = bdberl:get(Db, mykey).
  
  update_should_save_value_if_successful(Config) ->
      Db = ?config(db, Config),
  
negative.code:      transaction_should_commit_on_success,
       transaction_should_abort_on_exception,
       transaction_should_abort_on_user_abort,
       transaction_error_should_return_error, 
       update_should_save_value_if_successful,
       update_should_accept_args_for_fun,
       port_should_tune_transaction_timeouts,
  