Function transform_condition_or_part

sql/sql_derived.cc:1442–1481

*/

Item *transform_condition_or_part(THD *thd,
                                  Item *cond,
                                  Item_transformer transformer,
                                  uchar *arg)
{
  if (cond->type() != Item::COND_ITEM ||
      ((Item_cond*) cond)->functype() != Item_func::COND_AND_FUNC)
  {
    Item *new_item= cond->transform(thd, transformer, arg);
      // Indicate that the condition is not pushable
    if (!new_item)
      cond->clear_extraction_flag();
    return new_item;
  }

  List_iterator<Item> li(*((Item_cond*) cond)->argument_list());
  Item *item;
  while ((item=li++))
  {
    Item *new_item= item->transform(thd, transformer, arg);
    if (!new_item)
    {
      // Indicate that the condition is not pushable
      item->clear_extraction_flag();
      li.remove();
    }
    else
      li.replace(new_item);
  }

  switch (((Item_cond*) cond)->argument_list()->elements)
  {
  case 0:
    return NULL;
  case 1:
    return ((Item_cond*) cond)->argument_list()->head();
  default:
    return cond;
  }
}


/**