bookmarks 表似乎尚未投入使用。它是 Discourse 书签功能正在进行的某些改进的一部分。
目前，您可以通过如下查询获取有关书签的信息：
SELECT
t.user_id,
t.id AS topic_id,
COUNT(*) AS bookmark_count
FROM post_actions pa
JOIN posts p
ON p.id = pa.post_id
JOIN topics t
ON t.id = p.topic_id
WHERE pa.post_action_type_id = 1
AND t.deleted_at IS NULL
AND p.deleted_at IS NULL
GROUP BY t.id, t.user_id
ORDER BY bookmark_count DESC
LIMIT 20