code: public static void updateIndex(String indexName,
                                        List<FieldSort> fieldNames,
                                        Database database,
                                        SQLDatabaseQueue queue) throws QueryException {
          IndexUpdater updater = new IndexUpdater(database, queue);
  
          updater.updateIndex(indexName, fieldNames);
      }
docs: Update a single index.
  
  This index is assumed to already exist.
  
  @param indexName Name of index to update
  @param fieldNames List of field names in the sort format
  @param database The local {@link Database}
  @param queue The executor service queue
  @return index update success status (true/false)