Amount of content added to articles by top users in FA WP

SQL

use fawiki_p;
select rev_user_text, rev_year, sum(rev_id) / (1024 * 1024) content_added
from
(
select
  new.rev_id,
  substr(new.rev_timestamp, 1, 4) rev_year,
  new.rev_user_text,
  case
    when old.rev_len is null then new.rev_len
    when new.rev_len > old.rev_len then new.rev_len - old.rev_len
    else null
  end expansion
from revision new
join page
  on new.rev_page = page_id
left join revision old
  on old.rev_id = new.rev_parent_id
left join user_groups
  on ug_user = new.rev_user
  and ug_group = 'bot'
where
  page_namespace = 0
  and ug_user is null
  and new.rev_user_text in (
    select rev_user_text from
    (
      select rev_user_text, count(*)
      from revision
      where rev_user <> 0
      group by rev_user_text
      having count(*) > 15000
      order by 2 desc
    ) users_by_edits
  )
) exp
group by rev_user_text, rev_year
order by content_added desc
SQL

Checking query status...
