Thanks for the feedback blabla_bingo, I see the error. Yes, this is a mistake.

Here’s a working query for that example:

SELECT m.product_id, m.latest, MAX(b1.bug_id) AS latest_bug_id
FROM Bugs b1
JOIN BugsProducts p USING (bug_id)
JOIN (
  SELECT product_id, MAX(date_reported) AS latest
   FROM Bugs b2 JOIN BugsProducts USING (bug_id)
   GROUP BY product_id
) m
  ON (b1.date_reported = m.latest AND p.product_id = m.product_id)
GROUP BY m.product_id, m.latest;

I’ll try to get this correction into the next printing of the book.