monthly statistics of jawiki

SQL

use jawiki_p;
select
  a.month, 
  number_of_editor_include_anonymous_user,
  number_of_editor_exclude_anonymous_user,
  number_of_edits,
  number_of_edits_by_registered_user,
  number_of_edits_by_anonymous_user

from (
  select
    left( rev_timestamp, 6 ) as month,
    count( distinct rev_user ) as number_of_editor_include_anonymous_user
  from revision
  group by left(rev_timestamp, 6);
) as a

left outer join (
  select
    left( rev_timestamp, 6 ) as month,
    count( distinct rev_user ) as number_of_editor_exclude_anonymous_user
  from revision
  where
    rev_user != 0
  group by left(rev_timestamp, 6);
) as b on a.month = b.month

left outer join (
  select
    left( rev_timestamp, 6 ) as month,
    count(*) as number_of_edits
  from revision
  group by left(rev_timestamp, 6);
) as c on a.month = c.month

left outer join (
  select
    left( rev_timestamp, 6 ) as month,
    count(*) as number_of_edits_by_registered_user
  from revision
  where
    rev_user != 0
  group by left(rev_timestamp, 6);
) as d on a.month = d.month

left outer join (
  select
    left( rev_timestamp, 6 ) as month,
    count(*) as number_of_edits_by_anonymous_user
  from revision
  where
    rev_user = 0
  group by left(rev_timestamp, 6);
) as e on a.month = e.month
SQL

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