题解 | #推荐内容准确的用户平均评分#

select sum(score)/count(user_id)
from
(select t2.user_id,t2.score
from      recommend_tb t1
inner join user_action_tb t2
on        t1.rec_user=t2.user_id
and       t1.rec_info_l=t2.hobby_l
group by t2.user_id,t2.score)t 
#考虑同一用户有多个爱好标签，推送内容推送多个爱好也算一个的情况，对用户和分数进行分组去重
;