题解 | 网易云音乐推荐(网易校招笔试真题)

with likes as (
        select
            user_id,
            music_id,
            music_name
        from
            music_likes
            left join music on music_likes.music_id = music.id
)
select
    music_name
from
    likes
where
    (likes.user_id in (select follower_id from follow where user_id = '1'))
    and 
    (music_name not in (select music_name from likes where user_id = '1'))
group by music_id
order by music_id