一次从多个表中选择（多对多关系） - MySQL

Question

我有这些表：

电影信息：

• filminfo_id (int)
• filminfo_author (int)
• filminfo_title (varchar)
• filminfo_releaseYear (int)

类型：

• genre_id (int)
• genre_name (varchar)

电影流派：

• filmGenre_id (int)
• filmGenre_filmId (int)
• filmGenre_genreId (int)

用户

• user_id (int)
• user_firstname (varchar)
• user_lastname (varchar)

董事：

• director_id (int)
• director_firstname (varchar)
• director_lastname (varchar)

电影导演：

• filmDirector_id (int)
• filmDirector_filmId (int)
• filmDirector_directorId (int)

我想选择以下：

• filminfo_id
• 电影信息标题
• filminfo_releaseYear
• 流派名称（匹配电影流派）
• user_firstname（匹配 filminfo_author）
• user_lastname（匹配 filminfo_author）
• director_firstname（匹配电影导演）
• director_lastname（匹配电影导演）

我一整天都被这个问题困扰着。我喜欢能帮我解决这个问题的人！

到目前为止我做了什么：

SELECT
f.filminfo_title,
f.filminfo_releaseYear,
u.user_id,
u.user_firstName,
u.user_lastName,
d.director_firstname,
d.director_lastname,
GROUP_CONCAT(g.genre_name SEPARATOR ', ') genre
FROM (filmGenres fg, filmDirectors fd,filmActors fa) 
INNER JOIN filminfo f ON f.filminfo_id = fg.filmGenre_filmId  
INNER JOIN genres g ON g.genre_id = fg.filmGenre_genreId
INNER JOIN users u ON u.user_id = f.filminfo_author
INNER JOIN directors d ON d.director_id = fd.filmDirector_directorId
GROUP BY
f.filminfo_title,
f.filminfo_releaseYear
ORDER BY f.filminfo_releaseYear DESC
LIMIT 0,10;

请帮忙！

---

编辑：
我非常接近：

SELECT
    f.filminfo_title,
    f.filminfo_originalTitle,
    f.filminfo_suggestedAge,
    f.filminfo_runtime,
    f.filminfo_releaseYear,
    f.filminfo_description,
    f.filminfo_youtubeId,
    user_firstname,
    user_lastname,
    fi.filmImage_image,
    GROUP_CONCAT(genre_name SEPARATOR ', ') as genrenames,
    GROUP_CONCAT(CONCAT(director_firstname, ' ',
                        director_lastname) SEPARATOR ', ') as directors
FROM filmGenres fg
JOIN filminfo f ON f.filminfo_id = fg.filmGenre_filmId
JOIN users u ON u.user_id = f.filminfo_author
JOIN genres g ON g.genre_id = fg.filmGenre_genreId
JOIN filmDirectors fd ON fd.filmDirector_filmId = f.filminfo_id
JOIN directors d ON d.director_id = fd.filmDirector_directorId
JOIN filmImages fi ON fi.filmImage_id = f.filminfo_id
GROUP BY f.filminfo_title

但这会多次返回导演（例如：Ridley Scott、Ridley Scott）。我做错了什么？

Answer 1

Select 

    fi.filminfo_id,
    fi.filminfo_title,
    fi.filminfo_releaseYear,
    g.genre_name, -- (matching filmGenres)
    u.user_firstname, -- (matching filminfo_author)
    u.user_lastname, -- (matching filminfo_author)
    d.director_firstname, -- (matching filmDirectors)
    d.director_lastname -- (matching filmDirectors)

From filminfo fi, genres g, filmGenres fg, users u, directors d, filmdirectors fd

Where
        fg.filmGenre_filmId  = fi.filminfo_id
    and fd.filmId=fi.filmInfo_id
    and g.genre_id=fg.filmGenre_genreId
    and u.user_id=fi.filminfo_author
    and d.director_id=filmDirector_directorId

如果电影有多种类型、作者或导演，这将为同一部电影返回多行。我没有添加顺序，因为它似乎与回答问题无关紧要。

编辑

针对您编辑的问题，添加关键字 distinct，以便仅选择不同的行。如果您仍然得到重复的导演姓名，那是因为您的数据表明该电影只有一位导演，但有多个作者或流派。

SELECT DISTINCT
    f.filminfo_title,
    f.filminfo_originalTitle,
    f.filminfo_suggestedAge,
    f.filminfo_runtime,
    f.filminfo_releaseYear,
    f.filminfo_description,
    f.filminfo_youtubeId,
    user_firstname,
    user_lastname,
    fi.filmImage_image,
    GROUP_CONCAT(genre_name SEPARATOR ', ') as genrenames,
    GROUP_CONCAT(CONCAT(director_firstname, ' ',
                        director_lastname) SEPARATOR ', ') as directors
FROM filmGenres fg
JOIN filminfo f ON f.filminfo_id = fg.filmGenre_filmId
JOIN users u ON u.user_id = f.filminfo_author
JOIN genres g ON g.genre_id = fg.filmGenre_genreId
JOIN filmDirectors fd ON fd.filmDirector_filmId = f.filminfo_id
JOIN directors d ON d.director_id = fd.filmDirector_directorId
JOIN filmImages fi ON fi.filmImage_id = f.filminfo_id
GROUP BY f.filminfo_title

Answer 2

这里的问题是，由于多个导演与电影的关系，单独输出它们没有意义。我也连接了导演：

SELECT
    filmGenre_filmId,
    filminfo_title,
    filminfo_releaseYear,
    user_firstname,
    user_lastname,
    GROUP_CONCAT(genre_name SEPARATOR ', ') as genrenames,
    GROUP_CONCAT(CONCAT(director_firstname, ' ',
                        director_lastname) SEPARATOR ', ') as directors
FROM filmGenres fg
JOIN filminfo f ON filmGenre_filmId = filminfo_id
JOIN users u ON filminfo_author = user_id
JOIN genres g ON filmGenre_genreId = genre_id
JOIN filmDirectors fd ON filmGenre_filmId = filmDirector_filmId
JOIN directors d ON filmDirector_directorId = director_id 
GROUP BY filmGenre_filmId

UPD1：

这是一个需要一些优化的简化查询：

SELECT
    filminfo_id,
    filminfo_title,
    filminfo_releaseYear,
    user_firstname,
    user_lastname,
    genrenames,
    directors
FROM filminfo f
JOIN users u ON filminfo_author = user_id
JOIN (
    SELECT
        filmGenre_filmId,
        GROUP_CONCAT(genre_name SEPARATOR ', ') as genrenames
    FROM filmGenres
    JOIN genres g ON filmGenre_genreId = genre_id
    GROUP BY filmGenre_filmId
) as g ON filminfo_id = filmGenre_filmId
JOIN (
    SELECT
        filmDirector_filmId,
        GROUP_CONCAT(CONCAT(director_firstname, ' ',
                            director_lastname) SEPARATOR ', ') as directors
    FROM filmDirectors
    JOIN directors d ON filmDirector_directorId = director_id
    GROUP BY filmDirector_filmId
) as d ON filminfo_id = filmDirector_filmId