find items not rated by this user

Videos
+------+------------------+
| id   | uploaded_by_user |
+------+------------------+
|    1 | tom              |
|    2 | mark             |
|    3 | tom              |
|    4 | mark             |
|    5 | tom              |
|    6 | john             |
+------+------------------+

Video_ratings:
+----------+--------+---------------+
| video_id | rating | rated_by_user |
+----------+--------+---------------+
|        1 |      5 | tom           |
|        1 |      4 | mark          |
|        5 |      2 | mark          |
+----------+--------+---------------+

The simplest query we could come up with was:

select id from videos
where not exists
  (select video_id as id from video_ratings
   where videos.id=video_ratings.video_id
   and video_ratings.rated_by_user='mark'
  )
and uploaded_by_user != 'mark'