presto-main/src/main/java/io/prestosql/connector/informationschema/InformationSchemaConnector.java/InformationSchemaConnector/beginTransaction
class InformationSchemaConnector:    @Override
    public ConnectorTransactionHandle beginTransaction(TransactionId transactionId, IsolationLevel isolationLevel, boolean readOnly)
    {
        return new InformationSchemaTransactionHandle(transactionId);
    }