题解 | 网易云音乐推荐(网易校招笔试真题)

select music_name
FROM(
    select
    music_name,
    m.id
    from music m
    join music_likes ml on m.id = ml.music_id
    where user_id in (select
    follower_id
    from follow
    where user_id = 1
    )    
)b
where music_name not  in(select
    music_name
    from music m
    join music_likes ml on m.id = ml.music_id
    where user_id = 1
    )
group by id
order by id