Dab pairs with titles differing only in case

SQL

SET STATEMENT max_statement_time = 1 FOR
SELECT Pl.page_title, Pu.page_title
FROM categorylinks Cl
JOIN page Pl ON Pl.page_id = Cl.cl_from AND Pl.page_namespace = 0 AND Pl.page_title REGEXP "/^[A-Z][a-z]+(_\\(disambiguation\\))?$/"
JOIN page Pu ON Pu.page_namespace = 0 AND Pu.page_title = UPPER(Pl.page_title)
JOIN categorylinks Cu ON Cu.cl_from = Pu.page_id AND Cu.cl_type = 'page' AND Cu.cl_to = "All_disambiguation_pages"
WHERE Cl.cl_type = 'page' AND Cl.cl_to = "All_disambiguation_pages"
LIMIT 1;

SQL

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