code: @Override
      public <T> void postProcess(T anyContext) {
          Tuple2<List<String>, List<String>> dimsAndMetrics = (Tuple2<List<String>, List<String>>)anyContext;
          List<String> dims = dimsAndMetrics._1();
          List<String> metrics = dimsAndMetrics._2();
          Iterator<Map.Entry<String, String>> colIter = fetchDimensions.entrySet().iterator();
          while (colIter.hasNext()) {
              Map.Entry<String, String> entry = colIter.next();
              if (dims.contains(entry.getKey())) {
                  //No action.
              } else if (metrics.contains(entry.getKey())) {
                  fetchMetrics.add(entry.getKey());
                  colIter.remove();
              } else {//TODO: Handle error
                  
              }
          }
      }
docs: This method must be called prior to calling {@link SelectQueryMeta#getDataMap() }.
  Essentially splits columns into Dimensions and Metrics.
  @param <T>
  @param anyContext