code: public List<Map<String, Object>> queryListMap(String sql, Object[] params) {
          Connection conn = getConn();
          try {
              return conn.createQuery(sql)
                      .withParams(params)
                      .setAutoDeriveColumnNames(true)
                      .throwOnMappingFailure(false)
                      .executeAndFetchTable()
                      .asList();
          } finally {
              this.closeConn(conn);
              this.clean(null);
          }
      }
docs: Querying a List<Map>
  
  @param sql    sql statement
  @param params params
  @return List<Map>