Many to many relationships with ON DELETE CASCADE with Symfony and Doctrine

I want many people to have a lot of relationship with Symfony and Doctrine. This really one-to-many unidirectional association can be displayed through the join table as the docs indicate I am using a YAML file to set this up with the following code:

In Content.orm.yml file:

manyToMany:
  comments:
    cascade: ["persist","remove"]
    onDelete: CASCADE
    options:
      cascade:
        remove: true
        persist: true
        #refresh: true
        #merge: true
        #detach: true
    orphanRemoval: false
    orderBy: null
    targetEntity: Comment
    joinTable:
      name: content_comments
      joinColumns:
        content_id:
          referencedColumnName: id
      inverseJoinColumns:
        comment_id:
          referencedColumnName: id
          unique: true

      

        
        
        
      

    

This creates the following SQL commands:

$ php app/console doctrine:schema:update --dump-sql | grep -i "comment\|content"
CREATE TABLE comment (id INT AUTO_INCREMENT NOT NULL, text LONGTEXT NOT NULL, content_id INT NOT NULL, creation_date DATETIME NOT NULL, PRIMARY KEY(id)) DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci ENGINE = InnoDB;
CREATE TABLE contents (id INT AUTO_INCREMENT NOT NULL, user INT DEFAULT NULL, user_id INT NOT NULL,file VARCHAR(255) DEFAULT NULL, INDEX IDX_B4FA11778D93D649 (user), PRIMARY KEY(id)) DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci ENGINE = InnoDB;
CREATE TABLE content_comments (content_id INT NOT NULL, comment_id INT NOT NULL, INDEX IDX_D297CC584A0A3ED (content_id), UNIQUE INDEX UNIQ_D297CC5F8697D13 (comment_id), PRIMARY KEY(content_id, comment_id)) DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci ENGINE = InnoDB;
ALTER TABLE contents ADD CONSTRAINT FK_B4FA11778D93D649 FOREIGN KEY (user) REFERENCES users (id);
ALTER TABLE content_comments ADD CONSTRAINT FK_D297CC584A0A3ED FOREIGN KEY (content_id) REFERENCES contents (id);
ALTER TABLE content_comments ADD CONSTRAINT FK_D297CC5F8697D13 FOREIGN KEY (comment_id) REFERENCES comment (id);

      

        
        
        
      

    

But as you can see, FOREIGN KEY statements do not have an "ON DELETE CASCADE" batch, even I am trying to fit all the YAML annotations I found.

Because in code I am trying to remove the "content" object and all the "comments" associated with this code:

        $comments = $content->getComments();

        // Remove first the parent
        $entity_manager->remove($content);
        $entity_manager->flush();

        // Remove the childs
        foreach($comments as $comment)
        {
            $entity_manager->remove($comment);
        }

        $entity_manager->flush();

      

        
        
        
      

    

This will result in the following exception.

An exception occurred while executing 'DELETE FROM comment WHERE id = ?' with params [1]:\n\nSQLSTATE[23000]: Integrity constraint violation: 1451 Cannot delete or update a parent row: a foreign key constraint fails (`bb2server`.`content_comments`, CONSTRAINT `FK_D297CC5F8697D13` FOREIGN KEY (`comment_id`) REFERENCES `comment` (`id`))

      

        
        
        
      

    

So what am I doing wrong? Or how to get the doctrine to put "DELETE CASCADE" in many ways?

My only dirty workaround: It drops the SQL query and rebuilds itself, but I need this Doctrine to create the query in the: update schema to avoid my fix:

mysql> show create table content_comments;
+------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table            | Create Table                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
+------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| content_comments | CREATE TABLE `content_comments` (
  `content_id` int(11) NOT NULL,
  `comment_id` int(11) NOT NULL,
  PRIMARY KEY (`content_id`,`comment_id`),
  UNIQUE KEY `UNIQ_D297CC5F8697D13` (`comment_id`),
  KEY `IDX_D297CC584A0A3ED` (`content_id`),
  CONSTRAINT `FK_D297CC584A0A3ED` FOREIGN KEY (`content_id`) REFERENCES `contents` (`id`),
  CONSTRAINT `FK_D297CC5F8697D13` FOREIGN KEY (`comment_id`) REFERENCES `comment` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci |
+------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

mysql> ALTER TABLE content_comments DROP FOREIGN KEY FK_D297CC5F8697D13;
Query OK, 0 rows affected (0.04 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> ALTER TABLE content_comments ADD CONSTRAINT FK_D297CC5F8697D13 FOREIGN KEY (`content_id`) REFERENCES `contents` (`id`) ON DELETE CASCADE;
Query OK, 10 rows affected (0.07 sec)
Records: 10  Duplicates: 0  Warnings: 0

      

        
        
        
      

    

Edit: workaround. I need to put onDelete: CASCADE under JoinColumns

manyToMany:
  comments:
    cascade: ["persist","remove"]
    onDelete: CASCADE
    options:
      cascade:
        remove: true
        persist: true
        #refresh: true
        #merge: true
        #detach: true
    orphanRemoval: false
    orderBy: null
    targetEntity: Comment
    joinTable:
      name: content_comments
      joinColumns:
        content_id:
          referencedColumnName: id
          onDelete: CASCADE
      inverseJoinColumns:
        comment_id:
          referencedColumnName: id
          unique: true
          onDelete: CASCADE