SELECT p.id
FROM posts p,
     comments c,
     users u,
     badges b,
    (SELECT u.creationdate, MAX(u.upvotes) AS maxUpVotes FROM users u, posts p1 WHERE u.id = p1.owneruserid AND  u.creationdate > p1.creationdate GROUP BY u.creationdate) AS sub1,
    (SELECT MAX(relatedpostid) AS maxrelatedpostid  FROM postlinks) AS sub2
WHERE  c.postid = p.id
   AND u.id = p.owneruserid
   AND c.creationdate = sub1.creationdate
   AND u.upvotes = sub1.maxUpVotes
   AND sub2.maxrelatedpostid > p.id
   AND u.id = b.userid
   AND (b.name LIKE 'Research Assistant');