WP:NOTWEBHOST - Quarry

SQL

SELECT
	*,
    ((computed.userspace_contribs - sandbox_contribs) / computed.recent_contribs) AS contrib_ratio
FROM (
    SELECT
        raw.actor_name,
        COUNT(raw.rc_actor) AS recent_contribs,
        SUM(raw.in_userspace) AS userspace_contribs,
        SUM(raw.in_sandbox) AS sandbox_contribs
    FROM (
        SELECT
            recentchanges_userindex.*,
            actor.actor_name,
            CASE
                WHEN recentchanges_userindex.rc_namespace IN (2,3) THEN 1
                ELSE 0
            END AS in_userspace
      		CASE
      			WHEN recentchanges_userindex.rc_title LIKE '%/sandbox%' THEN 1
      			ELSE 0
      		END AS in_sandbox
        FROM recentchanges_userindex
            JOIN actor ON recentchanges_userindex.rc_actor = actor.actor_id
        WHERE recentchanges_userindex.rc_type IN (0,1)
            AND recentchanges_userindex.rc_bot = 0
        ORDER BY recentchanges_userindex.rc_timestamp DESC
    ) as raw
  	GROUP BY raw.rc_actor
  	HAVING total_contribs > 15
) as computed
WHERE contrib_ratio > 0.8
ORDER BY contrib_ratio DESC
LIMIT 500;
SQL

Checking query status...
