题解 | #推荐内容准确的用户平均评分#

SELECT ROUND(AVG(score), 3) AS avg_score
FROM (SELECT DISTINCT user_id, rec_info_l, score
      FROM recommend_tb r
               JOIN user_action_tb u ON r.rec_user = u.user_id
      WHERE rec_info_l = u.hobby_l) t;