Bad links from wikis to Commons categories: broken

SQL

#USE stop;
USE dewiki_p;
SELECT now() AS timestamp;
#empty links, no target given
(SELECT CONCAT ('# [[', REPLACE (wp.page_title, '_', ' '), ']]') AS wpage,
        CONCAT('→ [[:c:', REPLACE (iwl_title, '_', ' '), "]] → '''leer'''") AS commonscat
FROM iwlinks
INNER JOIN page wp
ON wp.page_id = iwl_from
AND wp.page_namespace = 0
WHERE iwl_prefix ='commons'
AND iwl_title = 'Category:'
)
UNION
#broken interwikilinks
(SELECT CONCAT ('# [[', REPLACE (wp.page_title, '_', ' '), ']]') AS wpage,
        CONCAT('→ [[:c:', REPLACE (iwl_title, '_', ' '), ']]',
               IF (iwl_title LIKE 'Category:', " → '''leer'''", ''),
               IF (iwl_title LIKE 'Category: %', " → '''Leerzeichen'''", ''),
               IF (iwl_title REGEXP '^Category\:Q\d+$', " → '''Murks'''", ''),
               IF (iwl_title REGEXP '\#', " → '''Murks'''", ''),
               IF (iwl_title REGEXP '[\,\.\?\"\(]$', " → '''Murks'''", ''),
               IF (iwl_title REGEXP '^Category\:[a-z]', " → '''Kleinbuchstabe'''", '')
              ) AS commonscat
FROM iwlinks
INNER JOIN page wp
ON wp.page_id = iwl_from
AND wp.page_namespace = 0
AND wp.page_is_redirect = 0
WHERE iwl_prefix ='commons'
AND iwl_title LIKE 'Category:%'
AND NOT EXISTS (SELECT 1 FROM commonswiki_p.page cp
                WHERE cp.page_title = SUBSTRING(iwl_title, 10)
                AND cp.page_namespace = 14)
)
UNION
#broken external interwiki links
(SELECT CONCAT('# [[', REPLACE (wp.page_title, '_', ' '), ']]') AS wpage,
        CONCAT('→ [[:c:', REPLACE ((SUBSTRING(REPLACE (el_to, '?uselang=de', ''), 36)), '_', ' '), ']]',
               IF (REPLACE (el_to, '?uselang=de', '') = 'https://commons.wikimedia.org/wiki/Category:', " → '''leer'''", ''),
               IF (el_to = 'https://commons.wikimedia.org/wiki/Category:?uselang=de', " → '''leer'''", ''),
               IF (el_to REGEXP '^https\:\/\/commons\.wikimedia\.org\/wiki\/Category\:Q\d+\?uselang\=de$', " → '''Murks'''", ''),
               IF (el_to REGEXP '^https\:\/\/commons\.wikimedia\.org\/wiki\/Category\:.*\#', " → '''Murks'''", ''),
               IF (el_to REGEXP '^https\:\/\/commons\.wikimedia\.org\/wiki\/Category\:[a-z]', " → '''Kleinbuchstabe'''", '')
              ) AS commonscat
 FROM externallinks
 INNER JOIN page wp
 ON wp.page_id = el_from
 AND wp.page_namespace = 0
 AND wp.page_is_redirect = 0
 WHERE el_to LIKE 'https://commons.wikimedia.org/wiki/Category:%'
 AND el_to NOT LIKE '%\%%' #temp
 AND NOT EXISTS (SELECT 1 FROM commonswiki_p.page cp
                 WHERE cp.page_namespace = 14
                 AND cp.page_title = SUBSTRING(REPLACE (el_to, '?uselang=de', ''), 45)
                )
)
ORDER BY wpage
LIMIT 3000;
SQL

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