code: private boolean isAggregate(String thriftColumnName)
      {
          if (thriftColumnName.startsWith(SYS_COUNT) || thriftColumnName.startsWith(SYS_MIN)
                  || thriftColumnName.startsWith(SYS_MAX) || thriftColumnName.startsWith(SYS_AVG)
                  || thriftColumnName.startsWith(SYS_SUM))
          {
              return true;
          }
          else if (thriftColumnName.startsWith(COUNT) || thriftColumnName.startsWith(MIN)
                  || thriftColumnName.startsWith(MAX) || thriftColumnName.startsWith(AVG)
                  || thriftColumnName.startsWith(SUM))
          {
              return true;
          }
          return false;
      }
docs: Checks if is aggregate.
  
  @param thriftColumnName
  the thrift column name
  @return true, if is aggregate