nlwiki Atypical displaytitle usage

SQL

USE nlwiki_p;
SELECT 
	page_namespace, 
    page_title, 
    pp_value AS displaytitle,
    LENGTH(page_title) as strlen1,
    LENGTH(CONVERT(page_title USING utf8mb4)) as strlen2,
    LOWER(LEFT(CONVERT(page_title USING utf8mb4), 1)) as c0,
    RIGHT(CONVERT(REPLACE(page_title,'_',' ') USING utf8mb4),LENGTH(CONVERT(page_title USING utf8mb4))-1) as 'right'
    CONCAT(LOWER(LEFT(CONVERT(page_title USING utf8mb4), 1)),RIGHT(CONVERT(REPLACE(page_title,'_',' ') USING utf8mb4),LENGTH(CONVERT(page_title USING utf8mb4))-1)) as lcfirst
FROM page, page_props
WHERE 
	page_namespace=0 AND
	page_id=pp_page AND 
    pp_propname='displaytitle' AND 
    /*pp_value=CONVERT(REPLACE(page_title,'_',' ') USING utf8mb4) OR */
    (
    	NOT (pp_value REGEXP '\\<i\\>' AND pp_value REGEXP '\\</i\\>' AND LENGTH(pp_value)=LENGTH(page_title)+7) AND
    	CONCAT(LOWER(LEFT(CONVERT(page_title USING utf8mb4), 1)),RIGHT(CONVERT(REPLACE(page_title,'_',' ') USING utf8mb4),LENGTH(CONVERT(page_title USING utf8mb4))-1))!=pp_value
	)
SQL

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