คิดเป็นรายเดือน ไม่จำเป็นต้องใช้ทุกตาราง
s by month.It is not neccessary to use all the tables.
 ReviewTasks:  Id [ number]  ReviewTaskTypeId [ number]  CreationDate [ time]  DeletionDate [ time]  ReviewTaskStateId [ number]  PostId [ number]  SuggestedEditId [ number]  CompletedByReviewTaskId [ number] 
SELECT TIME_TO_STR(e.CreationDate, '%M') AS "month", TIME_TO_STR(e.CreationDate, '%Y') AS "year", COUNT(DISTINCT e.PostId) AS closes FROM PostHistory AS c JOIN PostHistory AS e ON e.PostId = c.PostId WHERE c.CreationDate < e.CreationDate AND c.PostHistoryTypeId = 10 AND (e.PostHistoryTypeId = 4 OR e.PostHistoryTypeId = 5) GROUP BY TIME_TO_STR(e.CreationDate, '%M'), TIME_TO_STR(e.CreationDate, '%Y') ORDER BY TIME_TO_STR(e.CreationDate, '%Y'), TIME_TO_STR(e.CreationDate, '%M')