use hewiki_p;

select concat('# [[:קט:', replace(page_title, "_", " "), ']]') as category from page as p1

where page_namespace = 14

and not exists

(select * from categorylinks as c1

 where cl_from = page_id

 and exists

 (select * from page as p3

  where cl_to = page_title

  and page_namespace = 14

  and not exists

  (select * from categorylinks as c3

   where page_id = cl_from

   and cl_to = "קטגוריות_מוסתרות")))

and exists

(select * from categorylinks c5

 where cl_from = page_id)

​