Selecting entities associated with two other entities, joining three tables in Doctrine2 - php

Question

I have three types of entities,
Users
Groups
Websites
Users can have Websites, and they also can belong to Groups
Each of these entities has a name as well.
Here are my Doctrine2 definitions:
<?php
/** #Entity */
class User
{
// ...
/**
* #Column(type="string",length=255,nullable=false)
* #var string
*/
protected $name;
/**
* #ManyToMany(targetEntity="Group", inversedBy="users")
* #JoinTable(name="users_groups")
*/
private $groups;
/**
* #ManyToMany(targetEntity="Website", inversedBy="users")
* #JoinTable(name="users_websites")
*/
private $websites;
// ...
}
/** #Entity */
class Group
{
// ...
/**
* #Column(type="string",length=255,nullable=false)
* #var string
*/
protected $name;
/**
* #ManyToMany(targetEntity="User", mappedBy="groups")
*/
private $users;
// ...
}
/** #Entity */
class Website
{
// ...
/**
* #Column(type="string",length=255,nullable=false)
* #var string
*/
protected $name;
/**
* #ManyToMany(targetEntity="User", mappedBy="websites")
*/
private $users;
// ...
}
So now if I want to find all Users in a group called "Admins", I can do this:
$group = $em->getRepository("Group")->findOneByName("Admins");
$users = $group->users;
I can also get all users that are associated with website "Google.com" by doing:
$websites = $em->getRepository("Website")->findOneByName("Google.com");
$users = $websites->users;
Now if I want to get all users who are in "Admins", and are also associated with website "Google", what can I do?
If I was using TSQL, I would join the three tables, how do I do that in Doctrine?
Must I use DQL? How would the DQL look like?

Answer 1

You should use DQL for this.
SELECT u
FROM User u
JOIN u.groups g
JOIN u.websites w
WHERE
g.name = :group_name
AND w.name = :website_name
And the php code to do so:
$dql = '...'; // What i've written above
$query = $em->createQuery($dql);
$query->setParameter('group_name', 'Admins');
$query->setParameter('website_name', 'Google');
$users = $query->getResult();
I encourage you to read the doctrine ORM DQL documentation : http://docs.doctrine-project.org/projects/doctrine-orm/en/latest/reference/dql-doctrine-query-language.html
PS: The 2 lines of code you've written, should return groups, and websites, and not users