Delete Relationship Doctrine

In its simplest for I have a User and Category class, a User can belong to multiple Categories, defined as such

 class Application_Model_User {

    public function __construct() {
        $this->userCategory = new ArrayCollection();
    }
 /**
 * Unidirectional - Users have multiple categories they belong开发者_如何学JAVA to
 *
 * @ManyToMany(targetEntity="Application_Model_Category")
 * @JoinTable(name="user_category",
 *   joinColumns={@JoinColumn(name="user", referencedColumnName="id")},
 *   inverseJoinColumns={@JoinColumn(name="category", referencedColumnName="id")}
 * )
 */
}
    private $userCategory;

    public function getUserCategories() {
       return $this->userCategory;
  }
 }

Adding a Category for a user is easy, but I cannot understand or see from the doc's how I would delete a particular relationship... For instance if I did

    $thing = $em->getRepository('Application_Model_User');


$result = $thing->findOneBy(array(
  'id' => (int) 5
));
foreach($result->getUserCategories() as $category) {
    if($category->getName() == 'Another Sub Cat') {
        // Delete this relationship
    }               
}
$em->flush();

I would be able to delete the relationship, if I delete the entity using remove, the whole category is removed?

You should check out Working with Associations from the reference guide. It explains this.

<?php

class Application_Entity_User
{

            // ... snipped for brevity

    public function deleteCategory(Application_Entity_Category $category)
    {
        $this->userCategories->removeElement($category);
    }

}