Bad links from dewiki to other wikis: redirects

SQL

USE dewiki_p;
#SET @w = LEFT (DATABASE(), LENGTH(DATABASE()) - 2); SET @l = (SELECT lang FROM meta_p.wiki WHERE dbname = @w);
SET @l = 'de';
SET @lenb = LENGTH('https://de.wikibooks.org/wiki/');
SELECT now() AS timestamp;
##### Wikibooks #####
#interwiki links to article redirects
(SELECT CONCAT ('# [[', IF (wp.page_namespace = 14, ':Kategorie:', ''), REPLACE (wp.page_title, '_', ' '), ']] ',
                '→ [[b:', REPLACE (iwl_title, '_', ' '), ']]') AS wikipage
FROM iwlinks
INNER JOIN page wp
ON wp.page_id = iwl_from
AND wp.page_namespace IN (0, 14)
INNER JOIN dewikibooks_p.page cp
ON cp.page_title = iwl_title
AND cp.page_namespace = 0
AND cp.page_is_redirect = 1
WHERE iwl_prefix IN ('b', 'wikibooks')
AND iwl_title NOT LIKE 'Kategorie:%'
)
UNION
#external links to article redirects
(SELECT CONCAT('# [[', IF (wp.page_namespace = 14, ':Kategorie:', ''), REPLACE (wp.page_title, '_', ' '), ']] ',
               '→ [[b:', REPLACE (cp.page_title, '_', ' '), ']]') AS wikipage
FROM externallinks
INNER JOIN page wp
ON wp.page_id = el_from
AND wp.page_namespace IN (0, 14)
INNER JOIN dewikibooks_p.page cp
ON cp.page_title = SUBSTRING(REPLACE (el_to, CONCAT('?uselang=', @l), ''), IF ((LEFT (el_to, 5) = 'https'), @lenb + 1, @lenb))
AND cp.page_namespace = 0
AND cp.page_is_redirect = 1
WHERE ((el_to LIKE 'https://de.wikibooks.org/wiki/%') OR (el_to LIKE 'http://de.wikibooks.org/wiki/%'))
AND el_to NOT LIKE '%//de.wikibooks.org/wiki/Category:%'
AND el_to NOT LIKE '%\%%' #temp
)
#UNION
ORDER BY wikipage
LIMIT 100;
SQL

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