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我在 mysql 中有一个带有多个表的数据库,并且希望将多个表连接到一个视图中,以使我不必在 php 中构建 3 或 4 个 sql 语句甚至是一个大型连接语句来获取相同的信息。

这是我想加入的所有表格

track_title               
+----+------------------+
| ID |      TITLE       |
+----+------------------+
|  1 | Title Here       |
|  2 | Another Title    |
|  3 | Some Other Title |
+----+------------------+

track_artist
+----+----------------+-----------+-----------+
| ID | TRACK_TITLE_ID | ARTIST_ID | SYMBOL_ID |
+----+----------------+-----------+-----------+
| 1  | 1              | 1         | 2         |
| 2  | 1              | 2         | 1         |
| 3  | 3              | 1         | 1         |
+----+----------------+-----------+-----------+

artist

+----+-------------+
| ID | ARTIST      |
+----+-------------+
| 1  | Linkin Park |
| 2  | Metallica   |
+----+-------------+

symbol
+----+--------+
| ID | SYMBOL |
+----+--------+
| 1  |        |
| 2  | Feat.  |
+----+--------+

tracklisting
+----+----------+----------+---------------+---------+
| ID | TRACK NO | TITLE_ID | VERSION       | DISC NO |
+----+----------+----------+---------------+---------+
| 1  | 1        | 1        |               | 1       |
| 2  | 1        | 2        | Album Version | 1       |
| 3  | 1        | 3        | Live Version  | 1       |
+----+----------+----------+---------------+---------+

这是我正在寻找的最终视图

+----+----------+------------------+---------------+-----------------------------+---------+
| ID | TRACK NO | TITLE            | VERSION       | ARTIST                      | DISC NO |
+----+----------+------------------+---------------+-----------------------------+---------+
| 1  | 1        | Title Here       |               | Linkin Park Feat. Metallica | 1       |
| 2  | 1        | Another Title    | Album Version |                             | 1       |
| 3  | 1        | Some Other Title | Live Version  | Linkin Park                 | 1       |
+----+----------+------------------+---------------+-----------------------------+---------+

在过去的 3 天里,我一直在用左、右、加入和完全加入来抨击我的头,但似乎无法让它发挥作用。

基本上我想要发生的是 track_artist 表将从各自的表中获取艺术家和符号,并将它们连接到一列中。然后加入 title 和 concat 列来获得这个视图。

full_artist_view
+----------+------------------+-----------------------------+
| TITLE_ID | TITLE            | FULL_ARTIST                 |
+----------+------------------+-----------------------------+
| 1        | Title Here       | Linkin Park Feat. Metallica |
| 2        | Another Title    |                             |
| 3        | Some Other Title | Linkin Park                 |
+----------+------------------+-----------------------------+

我已经做到了这一点,但是当我尝试将其加入跟踪列表时,我似乎使我的服务器崩溃,这变得非常痛苦。没有mysql错误所以我猜我使用了错误的连接或者这是不可能的。(虽然我看不出这是不可能的)

tracklisting 表每周持续增长 1000 条记录,并且保持在 +- 75000 条记录。

对我来说,这是应该工作的 sql,但没有

FROM full_artist_view LEFT JOIN tracklisting ON 
full_artist_view.TITLE_ID = tracklisting.TITLE_ID
4

2 回答 2

1

虽然我只有你的小数据样本,但我看不到你的full_artist_view代码是什么样的。您应该能够使用以下方法获得结果:

select tt.id,
  tl.`track no`,
  tt.title,
  coalesce(tl.version, '') version,
  group_concat(concat(coalesce(a.artist, ''), ' ', coalesce(s.symbol, '')) order by a.artist SEPARATOR ' ') artist,
  tl.`disc no`
from track_title tt
inner join tracklisting tl
  on tt.id = tl.TITLE_ID
left join track_artist ta
  on tt.id = ta.TRACK_TITLE_ID
left join artist a
  on ta.artist_id = a.id
left join symbol s
  on ta.symbol_id = s.id
group by tt.id, tl.`track no`, tt.title, tl.version, tl.`disc no`

请参阅SQL Fiddle with Demo。这将返回:

| ID | TRACK NO |            TITLE |       VERSION |                       ARTIST | DISC NO |
---------------------------------------------------------------------------------------------
|  1 |        1 |       Title Here |               | Linkin Park Feat. Metallica  |       1 |
|  2 |        1 |    Another Title | Album Version |                              |       1 |
|  3 |        1 | Some Other Title |  Live Version |                 Linkin Park  |       1 |
于 2013-03-06T12:55:44.737 回答
0

快速播放,我认为(但不确定)你需要这样的东西:-

SELECT a.Id, a.Track_No, b.Title, a.Version, GROUP_CONCAT(CONCAT(d.Artists, e.Symbol)), a.Disc_No
FROM tracklisting a
INNER JOIN track_title b ON a.Title_id = b.Id
LEFT OUTER JOIN track_artist c ON b.Id = c.Track_Title_Id
LEFT OUTER JOIN artist d ON c.Artist_Id = d.Id
LEFT OUTER JOIN symbol e ON d.SymbolId = e.Id
GROUP BY a.Id, a.Track_No, b.Title, a.Version, a.Disc_No

但我可能错过了一些东西,所以让我知道!

于 2013-03-06T12:46:46.107 回答