Users by number of merges and merged data amount

SQL

USE wikidatawiki_p;
SELECT rev1.rev_user_text AS user_name, /*IFNULL(GROUP_CONCAT(DISTINCT ug_group),' ') AS user_group,*/
	COUNT(rev1.rev_id) AS number, SUM(rev1.rev_len) - SUM(rev2.rev_len) AS data_amount,
	(SUM(rev1.rev_len) - SUM(rev2.rev_len)) / COUNT(rev1.rev_id) AS ratio
	FROM (SELECT * FROM revision WHERE rev_comment LIKE '%wbmergeitems-from%') AS rev1
	JOIN revision AS rev2 ON rev2.rev_id = rev1.rev_parent_id
	#LEFT JOIN user_groups ON rev1.rev_user IS NOT NULL AND ug_user = rev1.rev_user
WHERE rev1.rev_len IS NOT NULL AND rev2.rev_len IS NOT NULL
GROUP BY rev1.rev_user_text HAVING COUNT(rev1.rev_id) > 50
ORDER BY number DESC, data_amount DESC, user_name;

SQL

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