class FlatMapNode extends SingleSourcePlanNode {

  @Override
  public Expression resolveSelect(final int idx, final Expression expression) {
    final Expression resolved = columnMappings.get(idx);
    return resolved == null ? expression : resolved;
  }

  public  FlatMapNode(
      final PlanNodeId id,
      final PlanNode source,
      final FunctionRegistry functionRegistry,
      final ImmutableAnalysis analysis
  );

}