docs: @Override
      protected UniversalIdIntQueueMessage readFromEphemeralStorage(Connection conn,
              IQueueMessage<Long, byte[]> msg) {
          Map<String, Object> dbRow = getJdbcHelper().executeSelectOne(conn, SQL_READ_FROM_EPHEMERAL,
                  msg.getId());
          if (dbRow != null) {
              UniversalIdIntQueueMessage myMsg = new UniversalIdIntQueueMessage();
              return myMsg.fromMap(dbRow);
          }
          return null;
      }