本文介绍了在 MySQL 中使用 Join 删除的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
这是创建我的表的脚本:
Here is the script to create my tables:
CREATE TABLE clients (
client_i INT(11),
PRIMARY KEY (client_id)
);
CREATE TABLE projects (
project_id INT(11) UNSIGNED,
client_id INT(11) UNSIGNED,
PRIMARY KEY (project_id)
);
CREATE TABLE posts (
post_id INT(11) UNSIGNED,
project_id INT(11) UNSIGNED,
PRIMARY KEY (post_id)
);
在我的 PHP 代码中，删除客户端时，我想删除所有项目帖子:
In my PHP code, when deleting a client, I want to delete all projects posts:
DELETE
FROM posts
INNER JOIN projects ON projects.project_id = posts.project_id
WHERE projects.client_id = :client_id;
posts 表没有外键 client_id，只有 project_id.我想删除项目中传递了 client_id 的帖子.
The posts table does not have a foreign key client_id, only project_id. I want to delete the posts in projects that have the passed client_id.
这现在不起作用，因为没有帖子被删除.
This is not working right now because no posts are deleted.
推荐答案
您只需要指定要从 posts 表中删除条目:
You just need to specify that you want to delete the entries from the posts table:
DELETE posts
FROM posts
INNER JOIN projects ON projects.project_id = posts.project_id
WHERE projects.client_id = :client_id
有关更多信息，您可以查看此替代答案
For more information you can see this alternative answer
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