presto-base-jdbc/src/main/java/io/prestosql/plugin/jdbc/JdbcConnector.java/JdbcConnector/rollback
class JdbcConnector:    @Override
    public void rollback(ConnectorTransactionHandle transaction)
    {
        JdbcMetadata metadata = transactions.remove(transaction);
        checkArgument(metadata != null, "no such transaction: %s", transaction);
        metadata.rollback();
    }