start with lower and upper (cyrillic) exist same time in zhwikt

SQL

USE zhwiktionary_p;
SELECT page.page_namespace, 
	CONCAT(case
		when page.page_namespace = 10 then "Template:"
		when page.page_namespace = 11 then "Template talk:"
		when page.page_namespace = 828 then "Module:"
		when page.page_namespace = 829 then "Module talk:"
		end, page.page_title) AS 'title1',
	CONCAT(case
		when page2.page_namespace = 10 then "Template:"
		when page2.page_namespace = 11 then "Template talk:"
		when page2.page_namespace = 828 then "Module:"
		when page2.page_namespace = 829 then "Module talk:"
		end, page2.page_title) AS 'title2'
FROM page
INNER JOIN page AS page2 ON CONCAT(
  UCASE(
	SUBSTRING(
	  CONVERT(
		page.page_title USING utf8
	  ), 1, 1
	)
  ), SUBSTRING(
	page.page_title, 2, LENGTH(page.page_title)-1
  )
) = page2.page_title
WHERE page.page_title REGEXP '^[аӑӓәӛӕбвгґѓғӷҕдђеѐёӗҽҿєжӂҗӝзз́ҙӟӡѕиѝӥӣіїӏйҋјкқҟҡӄҝлӆљмӎнӊңӈҥњоӧөӫҩпҧрҏсс́ҫтҭћќуўӳӱӯүұфхҳһцҵчӵҷӌҹџшщъыӹьҍэӭюя]'
	AND (
		(page.page_namespace = 10 AND page2.page_namespace = 10) OR 
		(page.page_namespace = 11 AND page2.page_namespace = 11) OR
		(page.page_namespace = 828 AND page2.page_namespace = 828) OR
		(page.page_namespace = 829 AND page2.page_namespace = 829)
	)
SQL

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