Many-To-Many relationship Doctrine - php

Question

I have had quite a few problems with my current entities mapping, so I wanted an opinion on what is the issue with it.
Let's say with have the following tables example with Doctrine, but also keep in mind that a Group can have many Users, and a User can be part of many Groups
User
--
id
name
Group
--
id
title
User Groups
--
id
user_id
group_id
And this is my current approach:
/**
* User
*
* #ORM\Table(name="user")
* #ORM\Entity(repositoryClass="SomeBundle\Entity\Repository\UserRepository")
*/
class User
{
/**
* #var integer
* #ORM\Id
* #ORM\Column(name="user_id", type="integer")
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $user_id;
// some other fields and functions here
}
Group
/**
* Group
*
* #ORM\Table(name="group", indexes={#ORM\Index(name="group_parent", columns={"parent_id"})})
* #ORM\Entity(repositoryClass="SomeBundle\Entity\Repository\GroupRepository")
*/
class Group
{
/**
* #var integer
*
* #ORM\Column(name="category_id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="IDENTITY")
*/
private $categoryId;
// some other functions and variables here
}
...and user_groups
/**
* User_Groups
*
* #ORM\Table(name="user_groups",
* indexes={
* #ORM\Index(name="user_group_user", columns={"user_id"}),
* #ORM\Index(name="user_group_group", columns={"group_id"})
* }
* )
* #ORM\Entity(repositoryClass="SomeBundle\Entity\Repository\UserGroupRepository")
*/
class UserGroup
{
/**
* #var integer
*
* #ORM\Id
* #ORM\Column(name="user_group_id", type="integer")
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $userGroupId;
/**
* #var \SomeBundle\Entity\User
* #ORM\Column(name="user_id")
*
* #ORM\ManyToMany(targetEntity="SomeBundle\Entity\User", inversedBy="userGroups")
* #ORM\JoinTable(name="users",
* joinColumns={#ORM\JoinColumn(name="user_id", referencedColumnName="userId")})
*/
private $user;
/**
* #var SomeBundle\Entity\Category
*
* #ORM\ManyToOne(targetEntity="SomeBundle\Entity\Group", inversedBy="groups")
* #ORM\JoinColumn(name="group_id", referencedColumnName="group_id")
*
*/
private $group;
/// etc
}
Any help would be appreciated!

Answer 1

/** #Entity **/
class User
{
// ...
/**
* #ManyToMany(targetEntity="Group", inversedBy="users")
* #JoinTable(name="users_groups")
**/
private $groups;
public function __construct() {
$this->groups = new \Doctrine\Common\Collections\ArrayCollection();
}
// ...
}
/** #Entity **/
class Group
{
// ...
/**
* #ManyToMany(targetEntity="User", mappedBy="groups")
**/
private $users;
public function __construct() {
$this->users = new \Doctrine\Common\Collections\ArrayCollection();
}
// ...
}
Your case is Many-to-Many, Bidirectional Association
Doctrine association mapping

Answer 2

In this example, I have a product and a mesureUnit they relate many to many.
In your case you only need user and group. The UserGroups is generated automatically.
Many to many relationship are done as follows:
<?php
namespace TeamERP\StoresBundle\Entity;
use Doctrine\ORM\Mapping AS ORM;
/**
* #ORM\Entity
*/
class MesureUnit
{
/**
* #ORM\Id
* #ORM\Column(type="integer")
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #ORM\Column(type="string", length=100, nullable=true)
*/
private $name;
/**
* #ORM\Column(type="string", length=10, nullable=true)
*/
private $abreviation;
/**
* #ORM\OneToMany(targetEntity="TeamERP\StoresBundle\Entity\ProductActivity", mappedBy="mesureUnit")
*/
private $pproductActivity;
/**
* #ORM\ManyToMany(targetEntity="TeamERP\StoresBundle\Entity\Product", mappedBy="mesureUnit")
*/
private $product;
/**
* Constructor
*/
public function __construct()
{
$this->pproductActivity = new \Doctrine\Common\Collections\ArrayCollection();
$this->product = new \Doctrine\Common\Collections\ArrayCollection();
}
Then the produc class could be like:
<?php
namespace TeamERP\StoresBundle\Entity;
use Doctrine\ORM\Mapping AS ORM;
/**
* #ORM\Entity
*/
class Product
{
/**
* #ORM\Id
* #ORM\Column(type="integer")
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #ORM\Column(type="string", length=50, nullable=true)
*/
private $code;
/**
* #ORM\Column(type="string", length=250, nullable=true)
*/
private $description;
/**
* #ORM\Column(type="datetime", nullable=true)
*/
private $date_received;
/**
* #ORM\OneToMany(targetEntity="TeamERP\StoresBundle\Entity\ProductActivity", mappedBy="product")
*/
private $pproductActivity;
/**
* #ORM\ManyToOne(targetEntity="TeamERP\StoresBundle\Entity\Category", inversedBy="product")
* #ORM\JoinColumn(name="category_id", referencedColumnName="id")
*/
private $category;
/**
* #ORM\ManyToOne(targetEntity="TeamERP\StoresBundle\Entity\AJob", inversedBy="product")
* #ORM\JoinColumn(name="job_id", referencedColumnName="id")
*/
private $aJob;
/**
* #ORM\ManyToMany(targetEntity="TeamERP\StoresBundle\Entity\MesureUnit", inversedBy="product")
* #ORM\JoinTable(
* name="MesureUnit2Product",
* joinColumns={#ORM\JoinColumn(name="product_id", referencedColumnName="id", nullable=false)},
* inverseJoinColumns={#ORM\JoinColumn(name="mesure_unit_id", referencedColumnName="id", nullable=false)}
* )
*/
private $mesureUnit;
/**
* Constructor
*/
public function __construct()
{
$this->pproductActivity = new \Doctrine\Common\Collections\ArrayCollection();
$this->mesureUnit = new \Doctrine\Common\Collections\ArrayCollection();
}
Yo do not need to create the table manually. It is generated by Doctrine.
Hope it helps