关闭。这个问题需要details or clarity .它目前不接受答案。
想改进这个问题?通过 editing this post 添加详细信息并澄清问题.
8年前关闭。
Improve this question
我想做一些内部连接但有错误 - 我做错了什么?
SELECT genre.title title1, country.title title2 FROM movie
-- genre
INNER JOIN genre ON genre.id = genreRelation.id_genre
INNER JOIN genreRelation ON movie.id = genreRelation.id_movie
-- country
INNER JOIN countryRelation ON movie.id = countryRelation.id_movie
INNER JOIN country ON country.id = countryRelation.id_country
WHERE movie.id = 1
最佳答案
您在连接中混合了未在 ON 子句中定义的表。
试试这个
SELECT genre.title title1, country.title title2 FROM movie
INNER JOIN countryRelation ON movie.id = countryRelation.id_movie
INNER JOIN genreRelation ON movie.id = genreRelation.id_movie
INNER JOIN genre ON genre.id = genreRelation.id_genre
LEFT JOIN country ON country.id = countryRelation.id_country
WHERE movie.id = 1
GROUP BY country.title
关于mysql - 几乎没有 JOIN 的 SQL,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/22284979/