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gistfile1.sql

SELECT username, count(distinct(document_id)) as reveditnum
FROM
(
SELECT username, document_id 
FROM wiki_revision wr 
JOIN auth_user au ON wr.creator_id = au.id
JOIN wiki_document wd ON wr.document_id = wd.id
WHERE created > '2012-10-24' and created <= '2013-04-24'
AND wd.locale = 'en-US'
UNION
SELECT username, document_id 
FROM wiki_revision wr
JOIN auth_user au ON wr.reviewer_id = au.id 
JOIN wiki_document wd ON wr.document_id = wd.id
WHERE is_approved 
AND reviewed > '2012-10-24' and reviewed <= '2013-04-24'
AND wd.locale = 'en-US'
) AS tablea
GROUP BY username ORDER BY reveditnum  DESC LIMIT 50