Ownerless user and user talk pages

SQL

use enwiktionary_p;

select * from (select
                 page_id as id,
                 page_namespace as ns,
                 page_title as title,
                 page_content_model as content_model,
                 page_len as len,
                 replace(regexp_replace(page_title, "/.*", ""), "_", " ") as potential_user_name,
               	 page_is_redirect as is_redirect
               from page 
               where page_namespace = 2
                 and page_title like "%/%"
               limit 1000)
as user_subpage
where
	potential_user_name not rlike '^[0-9]{1,3}[.][0-9]{1,3}[.][0-9]{1,3}[.][0-9]{1,3}$'
    and potential_user_name not rlike '(^([0-9]{1,3}[.]){3}[0-9]{1,3}$|^([[:alnum:]]{1,4}[:]){7})'
    and not exists (select 1 from user where user_name = potential_user_name limit 1);
SQL

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