EDIT

I tested and updated all existing users with the following queries. Delete duplicates and set inactive users to locked. Remaining 40 active users and 36 locked users.

SET @userId := 87;

 Select i.author_id, u.login from issues i join users u on ( i.author_id = u.id ) WHERE author_id = @userId ORDER BY u.login 
 ;
 Select i.assigned_to_id, u.login from issues i join users u on (  i.assigned_to_id = u.id) WHERE assigned_to_id = @userId  ORDER BY u.login 
 ;

 SELECT * From changesets cs WHERE user_id = @userId  ORDER BY user_id , committer ;

 SELECT * FROM journals WHERE user_id = @userId ORDER BY user_id
 ;
 SELECT user_id, count(*) FROM members WHERE user_id = @userId GROUP BY user_id ORDER BY user_id
 ;
 SELECT user_id, count(*) FROM members m INNER JOIN member_roles r ON r.member_id = m.id  WHERE user_id = @userId GROUP BY user_id ORDER BY user_id
 ;

  SELECT user_id user_preferences, count(*) FROM user_preferences WHERE user_id = @userId GROUP BY user_id ORDER BY user_id
  ;
  SELECT * FROM watchers WHERE user_id = @userId ORDER BY user_id
  ;
  SELECT *  FROM wiki_contents WHERE author_id = @userId ORDER BY author_id
  ;
SELECT * FROM wiki_content_versions WHERE author_id = @userId ORDER BY author_id

Open issues:

• Are the following users required?

  • trac (id = 10; author of 114 wiki_contents and wiki_content_versions); do we still need this wiki content? Probably it is Trac specific and not needed in Redmine
  • somebody (id = 22; not an owner of any content)
  • conversion (id = 125; not an owner of any content)
  • anonymous (id = 135; author of 4 wiki_content_versions; but maybe used elsewhere internally?)

• For the following locked users there is no known email address available: Magdy Zytomska, Veronika Kiss. Should we keep the foo.bar Email Adress

• Maybe we should set Email notification for all locked users to "No events". I have done this for many already but maybe not for all