题解 | 推荐内容准确的用户平均评分

SELECT 
AVG(score)
FROM user_action_tb
WHERE user_id IN(
    SELECT DISTINCT t1.rec_user
    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
)
AND hobby_l IN(
    SELECT hobby_l
    FROM user_action_tb
    WHERE user_id IN(
            SELECT DISTINCT t1.rec_user
            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
    )
)