@Override
    public OrcReader.FieldMapper create(OrcColumn column) {
      Map<Integer, OrcColumn> nestedColumns =
          uniqueIndex(column.getNestedColumns(), IcebergPageSourceProvider::getIcebergFieldId);

      int icebergId = getIcebergFieldId(column);
      return new IdBasedFieldMapper(
          nestedColumns, fieldNameToIdMappingForTableColumns.get(icebergId));
    }
Gets the index based dereference chain to get from the readColumnHandle to the
expectedColumnHandle
amoro-format-mixed/amoro-mixed-trino/src/main/java/org/apache/amoro/trino/unkeyed/IcebergPageSourceProvider.java