MySQL 如何从 Doctrine 中的连接表 (ManyToMany) 中删除行？
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How to delete rows from join-table (ManyToMany) in Doctrine?
提问by Dawid Ohia
I have a join-table which is created by using @ORM\ManyToManyannotation in Symfony2/Doctrine.
It joins Categoryand Parametertable.
我有一个连接表，它是通过@ORM\ManyToMany在 Symfony2/Doctrine 中使用注释创建的。它连接Category和Parameter表。
Now I want to delete all parameters from the Parameter table. Because there are foreign key constraints defined on join-table I can't just delete rows from Parameter table. First I have to delete child rows from join-table. But Dotrine's DQL syntax require to give a name of the entity, like:
现在我想从参数表中删除所有参数。因为在连接表上定义了外键约束，所以我不能只从参数表中删除行。首先，我必须从连接表中删除子行。但是 Dotrine 的 DQL 语法需要给出实体的名称，例如：
DELETE Project\Entity\EntityName
But what is the name of the join-table entity generated by using ManyToMany association? How to deal with it?
但是使用 ManyToMany 关联生成的连接表实体的名称是什么？如何处理？
Alternately, how can I set ON UPDATE CASCADE and ON DELETE CASCADE on foreign key constraints in join-table defined by @ORM\ManyToManyannotation.
或者，如何在@ORM\ManyToMany注释定义的连接表中的外键约束上设置 ON UPDATE CASCADE 和 ON DELETE CASCADE 。
EDIT:
编辑：
join-table schema:
连接表架构：
CREATE TABLE `categories_params` (
`category_id` INT(11) NOT NULL,
`param_id` INT(11) NOT NULL,
PRIMARY KEY (`category_id`, `param_id`),
INDEX `IDX_87A730CB12469DE2` (`category_id`),
INDEX `IDX_87A730CB5647C863` (`param_id`),
CONSTRAINT `categories_params_ibfk_1` FOREIGN KEY (`category_id`) REFERENCES `allegro_category` (`id`),
CONSTRAINT `categories_params_ibfk_2` FOREIGN KEY (`param_id`) REFERENCES `category_param` (`id`)
)
COLLATE='utf8_general_ci'
ENGINE=InnoDB;
on UPDATEand on DELETEby default are set to RESTRICT
on UPDATE并且on DELETE默认设置为RESTRICT
THE FINAL SOLUTION WOULD BE:
最终的解决方案是：
* @ORM\ManyToMany(targetEntity="CategoryParam", cascade={"persist","remove"})
* @ORM\JoinTable(name="categories_params",
* joinColumns={@ORM\JoinColumn(name="category_id", referencedColumnName="id", onDelete="CASCADE")},
* inverseJoinColumns={@ORM\JoinColumn(name="param_id", referencedColumnName="id", onDelete="CASCADE")})
回答by Inoryy
To set cascade on doctrine level:
在学说级别设置级联：
@ORM\ManyToMany(targetEntity="Target", inversedBy="inverse", cascade={"remove", "persist"})
More info: Doctrine2 Annotation Reference.
更多信息：Doctrine2 注释参考。
To set cascade on mysql level:
在 mysql 级别设置级联：
@ORM\JoinColumn(onDelete="CASCADE", onUpdate="CASCADE")
