Question

我有一个包含3个表的MYSQL Db：

艺术家（artist_id，名称）
专辑（album_i，标题）和第三个相关表：
albums_artists（album_id，artist_id）

我的目标是显示所有艺术家的列表，并列出每个艺术家的名字旁边，这个艺术家发布的所有专辑的标题。（专辑“仅属于”一位艺术家，艺术家当然可能拥有多张专辑）

如果可以获得如下结果，那就太好了。

1“ac / dc”3“让摇滚乐” 1“交流/直流”4“高压”
2“深紫色”45“机头”
2“深紫色”49“在岩石中”
3“motorhead”666“黑桃王牌”num

（每行中的第一个数字是artist_id，第二个是album_id）。

对此有什么合适的查询？

Answer 1

SELECT ar.artist_id, ar.name, al.album_id, al.title
    FROM artists ar
        INNER JOIN albums_artists aa
            ON ar.artist_id = aa.artist_id
        INNER JOIN albums al
            ON aa.album_id = al.album_id
    ORDER BY ar.name, al.title

而且，只是为了好玩，如果有艺术家尚未发布任何专辑，那该怎么办呢？

SELECT ar.artist_id, ar.name, al.album_id, al.title
    FROM artists ar
        LEFT JOIN albums_artists aa
            INNER JOIN albums al
                ON aa.album_id = al.album_id
            ON ar.artist_id = aa.artist_id
    ORDER BY ar.name, al.title

Answer 2

select
  artist_id,
  album_id,
  ...
from
  albums_artists
join albums on albums.id = albums_artists.album_id
join artists on artists.id = albums_artists.artist_id

Answer 3

这样的事情：

select ar.artist_id, ar.name, al.album_id, al.title
  from artists ar
  join album_artists aa on aa.artist_id = ar.artist_id
  join albums al on al.album_id = aa.album_id and ar.artist_id = aa.artist_id
order by ar.artist_id

Answer 4

select a.artist_id, a.name, al.album_id, al.title
from artists a, albums al, albums_artists ala
where a.artist_id = ala.artist_id
and ala.album_id = al.album_id
order by ala.artist_id

mysql通过关联表从2个表中检索数据

4 个答案: