class SubqueryFlattener {

    public DMLStatementNode flatten(DMLStatementNode stmt) throws StandardException {
        ResultSetNode resultSet = stmt.getResultSetNode();
        if (resultSet.getNodeType() == NodeTypes.SELECT_NODE) {
            selectStack = new Stack<>();
            currentSelectNode = null;
            selectNode((SelectNode)resultSet, stmt);
        }
        return stmt;
    }

    public  SubqueryFlattener(SQLParserContext parserContext);

}