code: public List<Row> search(ExtendedFilter filter)
      {
          SecondaryIndexSearcher mostSelective = getHighestSelectivityIndexSearcher(filter.getClause());
          if (mostSelective == null)
              return Collections.emptyList();
          else
              return mostSelective.search(filter);
      }
docs: Performs a search across a number of column indexes
  
  @param filter the column range to restrict to
  @return found indexed rows