All editors on German Wikipedia by registration date 2001–2003, 1+ edits 2021+

SQL

USE dewiki_p;
SELECT
  user_name,
  edits_after,
  user_registration
FROM user
INNER JOIN (SELECT
             rev_user_text AS edit_username,
             COUNT(rev_id) AS edits_after
            FROM revision_compat
            WHERE rev_timestamp > "20210101000000"
            GROUP BY edit_username
           ) AS last_edits
           ON user.user_name = edit_username
INNER JOIN (SELECT
             rev_user_text AS edit_username2,
             COUNT(rev_id) AS edits_before
            FROM revision_compat
            WHERE rev_timestamp > "20010101000000"
            AND rev_timestamp < "20030101000000"
            GROUP BY edit_username2
           ) AS before_edits
           ON user_name = edit_username2
WHERE edits_before >= "1"
AND edits_after >= "1"
AND user_registration IS NULL
ORDER BY edits_after DESC

SQL

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