Categories who are under hidden categories only (zhwiki_p)

SQL

/* WITH hc AS (
    -- list of hidden categories
	SELECT p.page_title, pp.pp_propname
	FROM page_props pp 
	LEFT JOIN page p ON (p.page_id = pp.pp_page)
	WHERE pp.pp_propname = 'hiddencat'
), p AS (
    -- list of categories
    SELECT page_id, page_title
    FROM page
    WHERE page_namespace = 14
)
SELECT p.page_title
FROM page p 
LEFT JOIN categorylinks cl ON p.page_id = cl.cl_from
LEFT JOIN hc ON cl.cl_to = hc.page_title
WHERE hc.pp_propname IS NULL
LIMIT 100
*/
SELECT count(*)
    FROM page
    WHERE page_namespace = 14

SQL

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