How would I list the students who started later than start year of student with id = 8871?
This is what I have so far:
SELECT sid s1
WHERE s1.started <= sid = '8871';
I'd use a self join where one side of the join contains the students you want and the the reference student 8871:
SELECT a.* FROM student a JOIN student b ON b.sid = '8871' AND a.started > b.started