PHP MySQL加入两张表

Question

我有两张表，歌曲和历史记录。歌曲表如下所示：

ID | title  | artist  | duration 
1 | some title | some artist | 83592 

历史表看起来像：

ID | title  | artist | duration | date_played 
5 | some title | some artist | 83592 | 2012-08-08 11:22:00 

我怎么会从歌曲表呼应ID，如果从历史上最新的条目标题和艺术家表匹配？

我试过SELECT * FROM history JOIN songs ON title=songs.title AND artist=songs.artist ORDER BY date_played DESC LIMIT 0, 1，但没有奏效。有任何想法吗？

Answer 1

SELECT s.ID 
FROM songs s 
INNER JOIN (SELECT * FROM history h ORDER BY date_played DESC LIMIT 1) lastHistory 
ON lastHistory.title = s.title AND lastHistory.artist = s.artist 

（Sqlfiddle）

Answer 2

入住这

select songs1.id,history1.title,history1.artist 
from songs as songs1,history as history1 
order by date_diplayed desc 

我的事情该查询解决您的问题

Answer 3

SELECT songs.* 
FROM songs, (SELECT * FROM history ORDER BY DESC date_played LIMIT 1) hist_view 
WHERE songs.title = hist_view.title 
    AND songs.artist = hist_view.artist 

上面的查询创建和最近播放的歌曲的内嵌视图称为hist_view（使用LIMIT和ORDER BY DESC）。然后，它会与歌曲表格一起在艺术家和标题的基础上找到匹配的歌曲。

我建议你在历史记录表中添加类似song_id的内容作为外键。

Answer 4

SELECT * FROM history A INNER JOIN songs B 
ON A.title=B.title AND A.artist=B.artist 
ORDER BY A.date_played DESC 

我的建议是在历史表中，您可以使用歌曲表的歌曲ID而不是艺术家和标题。

表：歌曲

ID | title  | artist  | duration 
1 | some title | some artist | 83592 

表：历史

ID | songid | date_played 
5 | 1  | 2012-08-08 11:22:00 

这样就可以把您的模式进行一些优化。

然后你可以试试这个查询。

SELECT * FROM history A INNER JOIN songs B 
ON A.songid=B.ID ORDER BY A.date_played DESC 

Answer 5

您可以使用

SELECT songs.id 
FROM  songs, 
     history 
WHERE songs.title = history.title 
AND  songs.artist = history.artist 
ORDER BY history.date_played DESC 

或

SELECT  songs.id 
FROM  songs 
INNER JOIN history ON history.title = songs.title 
        AND history.artist = songs.artist 
ORDER BY history.date_played DESC 

但它会更好，如果你组织你的表由维奈的建议。