Mysql select most recent with date desc for each artist - mysql

Question

i have 3 tables:
PK: Primary Key
FK: Foreign Key
mp3s table:
+---------+--------------+----------------------+
| id (PK) | tarck_title | date |
+---------+--------------+----------------------+
| 100 | shakira | 2001-01-12 00:00:00 |
| 101 | metallica | 2002-01-12 00:00:00 |
| 102 | james blunt | 2003-01-12 00:00:00 |
| 103 | shakira | 2004-01-12 00:00:00 |
| 104 | anathema | 2005-01-12 00:00:00 |
| 105 | nelson | 2006-01-12 00:00:00 |
| 106 | shakira | 2007-01-12 00:00:00 |
| 107 | bb king | 2008-01-12 00:00:00 |
| 108 | metallica | 2009-01-12 00:00:00 |
| 109 | nelson | 2010-01-12 00:00:00 |
| 110 | shakira | 2011-01-12 00:00:00 |
| 111 | bb king | 2012-01-12 00:00:00 |
+---------+--------------+----------------------+
artists table:
+---------+----------------+
| id (PK) | artist_name |
+---------+----------------+
| 14 | shakira |
| 221 | metallica |
| 320 | james blunt |
| 328 | shakira |
| 1004 | anathema |
| 1140 | nelson |
| 1401 | bb king |
+---------+----------------+
and tags table: PK(mp3_id, artist_id)
+-------------+----------------+
| mp3_id (FK) | artist_id (FK) |
+-------------+----------------+
| 100 | 14 |
| 101 | 221 |
| 102 | 320 |
| 103 | 14 |
| 104 | 1004 |
| 105 | 1140 |
| 106 | 14 |
| 107 | 1401 |
| 108 | 221 |
| 109 | 1140 |
| 110 | 14 |
| 111 | 1401 |
+---------+--------------------+
now, i need good query for this resaults. i want select 3 latest track from (shakira & bb king) order by date track. like this:
+---------+--------------+----------------------+
| id (PK) | tarck_title | date |
+---------+--------------+----------------------+
| 110 | shakira | 2011-01-12 00:00:00 |
| 106 | shakira | 2007-01-12 00:00:00 |
| 103 | shakira | 2004-01-12 00:00:00 |
| 111 | bb king | 2012-01-12 00:00:00 |
| 107 | bb king | 2008-01-12 00:00:00 |
+---------+--------------+----------------------+
or select 3 latest track from (shakira & bb king & metallica) order by date track. like this:
+---------+--------------+----------------------+
| id (PK) | tarck_title | date |
+---------+--------------+----------------------+
| 110 | shakira | 2011-01-12 00:00:00 |
| 106 | shakira | 2007-01-12 00:00:00 |
| 103 | shakira | 2004-01-12 00:00:00 |
| 111 | bb king | 2012-01-12 00:00:00 |
| 107 | bb king | 2008-01-12 00:00:00 |
| 108 | metallica | 2009-01-12 00:00:00 |
| 101 | metallica | 2002-01-12 00:00:00 |
+---------+--------------+----------------------+
EDIT:
this query is working but sort date desc not working:
SELECT `id`, `tarck_title`, `date`
FROM `mp3s`
WHERE `id` IN (
SELECT x.`mp3_id`
FROM `tags` x
INNER JOIN `tags` y ON y.`artist_id` = x.`artist_id` AND y.`mp3_id` <= x.`mp3_id`
INNER JOIN `mp3s` z ON z.`id` = x.`mp3_id`
WHERE x.`artist_id` IN (SELECT `artist_id` FROM `tags` WHERE `mp3_id` = 103)
GROUP BY x.`mp3_id` HAVING COUNT(*) <= 3
ORDER BY z.`date` DESC, x.`artist_id` DESC, x.`mp3_id`)

Answer 1

If I found the question, the query would be like the following:
(SELECT m.* FROM (tags as t JOIN artists as a on t.artist_id = a.id) JOIN mp3s as m on m.id = t.mp3_id
WHERE a.artist_name = 'Shakira'
ORDER BY m.date DESC
LIMIT 3)
UNION
(SELECT m.* FROM (tags as t JOIN artists as a on t.artist_id = a.id) JOIN mp3s as m on m.id = t.mp3_id
WHERE a.artist_name = 'bb King'
ORDER BY m.date DESC
LIMIT 3);
Also, If you want a compressed format of the query, you can find it in this post.

Answer 2

In MySQL, you can do this with variables:
SELECT m.*
FROM (SELECT m.*,
(#rn := if(#a = a.id, #rn + 1,
if(#a := a.id, 1, 1)
)
) as rn
FROM tags t JOIN
artists a
ON t.artist_id = a.id JOIN
mp3s m
ON m.id = t.mp3_id CROSS JOIN
(SELECT #a := -1, #rn := 0) params
WHERE . . .
ORDER BY a.id, m.date DESC
) m
WHERE rn <= 3;
In the inner WHERE, you can specify whatever artists or other conditions that you like.