Function find_unit_handler

sql/sql_union.cc:1365–1378

*/

static select_handler *find_unit_handler(THD *thd,
                                         SELECT_LEX_UNIT *unit)
{
  if (unit->outer_select())
    return nullptr;

  for (SELECT_LEX *sl= unit->first_select(); sl; sl= sl->next_select())
  {
    select_handler *uh= find_unit_handler_for_lex(thd, sl, unit);
    if (uh)
      return uh;
  }
  return nullptr;
}


inline bool st_select_lex_unit::rename_item_list(TABLE_LIST *derived_arg)