กิจกรรมประจำปีตามปีที่ลงทะเบียน ไม่จำเป็นต้องใช้ตารางทั้งหมด
Yearly activity by year of registration.It is not neccessary to use all the tables.
 PostLinks:  Id [ number]  CreationDate [ time]  PostId [ number]  RelatedPostId [ number]  LinkTypeId [ number] 
SELECT TIME_TO_STR(Posts.CreationDate, '%Y') AS PostYear, CAST(TIME_TO_STR(Users.CreationDate, '%Y') AS TEXT) AS RegYear, COUNT(*) AS Count FROM Posts, Users WHERE Posts.OwnerUserId = Users.Id AND Posts.CreationDate > Users.CreationDate GROUP BY TIME_TO_STR(Users.CreationDate, '%Y'), TIME_TO_STR(Posts.CreationDate, '%Y') ORDER BY RegYear, PostYear