Method check_pushable_cond

sql/item.cc:8138–8166

*/

void Item::check_pushable_cond(Pushdown_checker checker, uchar *arg)
{
  clear_extraction_flag();
  if (type() == Item::COND_ITEM)
  {
    bool and_cond= ((Item_cond*) this)->functype() == Item_func::COND_AND_FUNC;
    List_iterator<Item> li(*((Item_cond*) this)->argument_list());
    uint count= 0;
    Item *item;
    while ((item=li++))
    {
      item->check_pushable_cond(checker, arg);
      if (item->get_extraction_flag() !=  MARKER_NO_EXTRACTION)
        count++;
      else if (!and_cond)
        break;
    }
    if ((and_cond && count == 0) || item)
    {
      set_extraction_flag(MARKER_NO_EXTRACTION);
      if (and_cond)
        li.rewind();
      while ((item= li++))
        item->clear_extraction_flag();
    }
  }
  else if (!((this->*checker) (arg)))
    set_extraction_flag(MARKER_NO_EXTRACTION);
}


/**