Articles with most langlinks in one wiki, missing from another

*** May require further optimization for huge wikis (e.g. EN as source wiki). Additional condition on temporary dataset (before sort and limit) would be helpful, maybe limit via minimal number of langlinks for page to be considered.

SQL

USE cswiki_p;  -- articles from CS with most langlinks...

SELECT 
    count(*) ll_count, 
    page_title title_cs, 
    (select ll_title from langlinks where ll_from = page_id and ll_lang = 'en') title_en,
    (select ll_title from langlinks where ll_from = page_id and ll_lang = 'de') title_de,
    (select ll_title from langlinks where ll_from = page_id and ll_lang = 'pl') title_pl,
    (select ll_title from langlinks where ll_from = page_id and ll_lang = 'hu') title_hu
  FROM 
    page, langlinks
  WHERE
    ll_from = page_id and
    -- (select count(*) from langlinks where ll_from = page_id) >= 30 and
      -- attempt to limit number of intermediate rows to fetch and sort
    page_id not in (select ll_from from langlinks where ll_lang = 'sk') and
      -- ... missing from SK (no direct iw equivalent there)
    page_namespace = 0
  GROUP BY
    page_id
  ORDER BY 
    ll_count desc, page_title
  LIMIT
    2050;  -- top N

SQL

Checking query status...