protected void addQueryAfterUse(Batchable<?, ?> b) {
    if (b.queries == null) {
      return;
    }
    if (queries == null) {
      queries = new ArrayList<>(b.queries);
    } else {
      queries.addAll(b.queries);
    }
  }
Base class to add the batch process for DirectSQL or RawStore queries.
 1. Provide the implementation of run() to process one batch
 2. Call Batchable.runBatched() to process the whole dataset

 I: input type, R: result type
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/Batchable.java