presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/storage/OrcStorageManager.java/OrcStorageManager/columnIdIndex
class OrcStorageManager:    private static Map<Long, OrcColumn> columnIdIndex(List<OrcColumn> columns)
    {
        return uniqueIndex(columns, column -> Long.valueOf(column.getColumnName()));
    }