code: public ViewQuery reduce(final boolean reduce) {
          params[PARAM_REDUCE_OFFSET] = "reduce";
          params[PARAM_REDUCE_OFFSET+1] = Boolean.toString(reduce);
          return this;
      }
docs: Explicitly enable/disable the reduce function on the query.
  
  @param reduce if reduce should be enabled or not.
  @return the {@link ViewQuery} object for proper chaining.