bool Aggregator_distinct::unique_walk_function_for_count(void *element)
{
  Item_sum_count *sum= (Item_sum_count *)item_sum;
  sum->count++;
  return 0;
}
bool Aggregator_distinct::unique_walk_function_for_count(void *element)
{
  Item_sum_count *sum= (Item_sum_count *)item_sum;
  sum->count++;
  return 0;
}