code: public List executeScalarQuery(String cqlQuery) {
          CqlResult cqlResult = null;
          List results = new ArrayList();
          try {
              if (log.isDebugEnabled()) {
                  log.debug("Executing query {}.", cqlQuery);
              }
              cqlResult = (CqlResult) executeCQLQuery(cqlQuery, true);
  
              if (cqlResult != null && (cqlResult.getRows() != null || cqlResult.getRowsSize() > 0)) {
                  results = new ArrayList<Object>(cqlResult.getRowsSize());
                  Iterator<CqlRow> iter = cqlResult.getRowsIterator();
                  while (iter.hasNext()) {
                      Map<String, Object> entity = new HashMap<String, Object>();
  
                      CqlRow row = iter.next();
                      for (Column column : row.getColumns()) {
                          if (column != null) {
                              String thriftColumnName =
                                  PropertyAccessorFactory.STRING.fromBytes(String.class, column.getName());
  
                              if (column.getValue() == null) {
                                  entity.put(thriftColumnName, null);
                              } else {
                                  entity.put(thriftColumnName,
                                      composeColumnValue(cqlResult.getSchema(), column.getValue(), column.getName()));
                              }
                          }
                      }
                      results.add(entity);
                  }
              }
          } catch (Exception e) {
              log.error("Error while executing native CQL query Caused by {}.", e);
              throw new PersistenceException(e);
          }
          return results;
      }
docs: Execute scalar query.
  
  @param cqlQuery
  the cql query
  @return the list