private void closeConn(HiveConnection conn) {
    if (conn != null) {
      try {
        conn.close();
      } catch (SQLException e) {
        LOG.debug("Error closing connection {}", e.toString());
      }
    }
  }
Set the specified schema to the resultset
@param colNames
@param colTypes
jdbc/src/java/org/apache/hive/jdbc/HiveQueryResultSet.java