正确保留Symfony中的相关实体（外键）

你可以这样做：

    
      <?php
/* @Entity /
class Company
{
    // …
/**
 * @ManyToMany(targetEntity="Location", inversedBy="companies")
 * @JoinTable(name="company_location")
 */
private $locations;
public function __construct() {
    $this->locations = new \Doctrine\Common\Collections\ArrayCollection();
}
// ...
}
/ @Entity */
class Location
{
    // …
    /
 * @ManyToMany(targetEntity="Company", mappedBy="locations")
 */
private $companies;
public function __construct() {
    $this->companies = new \Doctrine\Common\Collections\ArrayCollection();
}
// ...
}
</code>