以下是表格结构。
一部电影可以映射多种类型,因此tbl_movie_genre
的情况下存在多对多关系。
我有电影详情页面,我正在获取电影ID。我必须编写查询来执行以下任务。
我必须为给定的电影ID找到具有所有匹配类型的电影。
例如我有电影ID 45,这部电影属于类型喜剧和浪漫,然后我必须找到所有其他类型喜剧和浪漫的电影。不应该填充只有喜剧或只有浪漫的电影。
是否可以在单个查询中执行此操作?
更新
在以下示例中,只有前2部电影符合标准。 “Hum tum ke pyar”和“housefull”。
drop table if exists tbl_movie_master, tbl_genre_master, tbl_movie_genre ;
create table tbl_movie_master (movie_id int, title varchar(100));
insert into tbl_movie_master values (1, 'Hum tum ke pyar'), (2, 'housefull'), (3, 'ek vakta ke liye'), (4, 'chalo pyar kare');
create table tbl_genre_master (genre_id int, genre varchar(100));
insert into tbl_genre_master values (1, 'horror'), (2, 'remoance'), (3, 'suspense'), (4, 'social');
create table tbl_movie_genre (movie_id int, genre_id int);
insert into tbl_movie_genre values (1, 1), (1, 2), (2, 1), (2, 2), (3, 3), (4, 1), (4,4);
mysql> select * from tbl_movie_master;
+----------+------------------+
| movie_id | title |
+----------+------------------+
| 1 | Hum tum ke pyar |
| 2 | housefull |
| 3 | ek vakta ke liye |
| 4 | chalo pyar kare |
+----------+------------------+
4 rows in set (0.00 sec)
mysql> select * from tbl_genre_master;
+----------+----------+
| genre_id | genre |
+----------+----------+
| 1 | horror |
| 2 | remoance |
| 3 | suspense |
| 4 | social |
+----------+----------+
4 rows in set (0.00 sec)
mysql> select * from tbl_movie_genre;
+----------+----------+
| movie_id | genre_id |
+----------+----------+
| 1 | 1 |
| 1 | 2 |
| 2 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 1 |
| 4 | 4 |
+----------+----------+
7 rows in set (0.00 sec)
SELECT m.*
FROM tbl_movie_master m
JOIN tbl_movie_genre mg ON mg.movie_id = m.movie_id
WHERE mg.genre_id = ALL (SELECT mg.genre_id FROM tbl_movie_genre mg WHERE mg.movie_id = 1);
Empty set (0.00 sec)
SELECT m.title
FROM tbl_movie_master m
JOIN tbl_movie_genre allgenres
ON m.movie_id= allgenres.movie_id
JOIN
(SELECT genre_id FROM tbl_movie_genre WHERE movie_id=1) somegenres
ON somegenres.genre_id=allgenres.genre_id;
+-----------------+
| title |
+-----------------+
| Hum tum ke pyar |
| Hum tum ke pyar |
| housefull |
| housefull |
| chalo pyar kare |
+-----------------+
5 rows in set (0.00 sec)
SELECT M.`title`, G.`genre`, M2.`title`
FROM tbl_movie_master AS M, tbl_movie_genre AS A
LEFT JOIN tbl_movie_master AS M2 ON A.`movie_id` = M2.`movie_id`
LEFT JOIN tbl_genre_master AS G ON A.`genre_id` = G.`genre_id`
WHERE M.`movie_id` = 1;
+-----------------+----------+------------------+
| title | genre | title |
+-----------------+----------+------------------+
| Hum tum ke pyar | horror | Hum tum ke pyar |
| Hum tum ke pyar | remoance | Hum tum ke pyar |
| Hum tum ke pyar | horror | housefull |
| Hum tum ke pyar | remoance | housefull |
| Hum tum ke pyar | suspense | ek vakta ke liye |
| Hum tum ke pyar | horror | chalo pyar kare |
| Hum tum ke pyar | social | chalo pyar kare |
+-----------------+----------+------------------+
7 rows in set (0.00 sec)
答案 0 :(得分:2)
SELECT m.*
FROM movie m
JOIN movie_genre mg ON mg.movie_id = m.id
WHERE mg.id = ALL (SELECT mg.genre_id FROM movie_genre mg WHERE mg.movie_id = ?)
而?
是给定的电影ID
答案 1 :(得分:1)
尝试:
SELECT m.title
FROM tbl_movie_master m
JOIN tbl_movie_genre allgenres
ON m.movie_id= allgenres.movie_id
JOIN
(SELECT genre_id FROM tbl_movie_genre WHERE movie_id=45) somegenres
ON somegenres.genre_id=allgenres.genre_id;
答案 2 :(得分:0)
这个问题为JOINs大声呼喊。
这样的事情会起作用:
SELECT M.`title`, G.`genre`, M2.`title`
FROM tbl_movie_master AS M, tbl_movie_genre AS A
LEFT JOIN tbl_movie_master AS M2 ON A.`movie_id` = M2.`movie_id`
LEFT JOIN tbl_genre_master AS G ON A.`genre_id` = G.`genre_id`
WHERE M.`movie_id` = A.`movie_id`
AND M.`title` = "Your Movie";
答案 3 :(得分:0)
需要在dnagirl的答案中添加“group by”以获得完全相同的类别数量。我想这就是我要找的......
SELECT mg1.movie_id,
mm1.title,
COUNT(*) AS cnt
FROM tbl_movie_genre AS mg1
INNER JOIN tbl_movie_master AS mm1
ON mg1.movie_id = mm1.movie_id
INNER JOIN (SELECT genre_id
FROM tbl_movie_genre
WHERE movie_id = 1) AS tt1
ON mg1.genre_id = tt1.genre_id
GROUP BY movie_id
HAVING cnt = (SELECT COUNT(*) AS mycnt
FROM tbl_movie_genre
WHERE movie_id = 1);