@Override
  public List<CompactionMetricsData> getTopCompactionMetricsDataPerType(int limit)      
      throws MetaException {
    return new TopCompactionMetricsDataPerTypeFunction(limit).execute(jdbcResource);
  }
Returns the min txnid seen open by any active transaction
@deprecated remove when min_history_level is dropped
@return txnId
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/txn/CompactionTxnHandler.java