Converting table to insert-only acid may open a txn in an inappropriate place

HiveTxnManager txnManager = SessionState.get().getTxnMgr();
      if (txnManager.isTxnOpen()) {
        mmWriteId = txnManager.getCurrentTxnId();
      } else {
        mmWriteId = txnManager.openTxn(new Context(conf), conf.getUser());
        txnManager.commitTxn();
      }