Symfony - how to make Doctrine search in abstract mapped superclass? - php

Question

I am building an online shop for plastic model makers (hence the 'model').
I have a Product mapped superclass because I want all products (models, tools, paints etc. to have name, price and description):
<?php
namespace AppBundle\Entity;
use Doctrine\ORM\Mapping as ORM;
use Doctrine\ORM\Mapping\MappedSuperclass;
use Gedmo\Mapping\Annotation as Gedmo; // gedmo annotations
/** #MappedSuperclass */
abstract class Product
{
/**
* #ORM\Column(type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #var string
* #ORM\Column(type="string", length=100, nullable=false)
*/
protected $name;
/**
* #var int
* #ORM\Column(type="decimal", scale=2, nullable=false)
*/
protected $price;
/**
* #var string
* #ORM\Column(type="text", nullable=true)
*/
protected $description;
/**
* #Gedmo\Timestampable(on="create")
* #ORM\Column(type="datetime")
*/
private $createdAt;
/**
* #ORM\Column(type="datetime")
* #Gedmo\Timestampable(on="update")
*/
private $updatedAt;
//getters and setters...
}
Then, there's a Model class, for plastic models, this extends the Product class but also has a Category for being able to search from cars, aircraft, ships etc:
<?php
namespace AppBundle\Entity;
use Doctrine\ORM\Mapping as ORM;
/**
* #ORM\Entity
* #ORM\Table(name="model")
*/
class Model extends Product
{
/**
* #var Category
* #ORM\ManyToOne(targetEntity="AppBundle\Entity\Category", inversedBy="models")
* #ORM\JoinColumn(name="category_id", referencedColumnName="id", nullable=true)
*/
private $category;
/**
* #return Category
*/
public function getCategory()
{
return $this->category;
}
/**
* #param Category $category
*/
public function setCategory($category)
{
$this->category = $category;
}
}
There will of course be more classes extending Product mapped superclass. Now I want to select the 10 most recently added products, regardless of their kind (models, tools, paints).
How can I tell Doctrine to give me the last 10 added products? Of course I tried something like:
$this->getDoctrine()->getManager()->getRepository("AppBundle:Product");
but of course it throws an exception saying that
SQLSTATE[42S02]: Base table or view not found: 1146 Table
'modeller_app.product' doesn't exist
which obviously is true, because Product is an abstract class and not actually an entity. How can I solve this problem?

Answer 1

You need to use class table inheritance.
Here is a example:
/**
* #ORM\Entity
* #ORM\Table(name="product")
* #InheritanceType("JOINED")
* #DiscriminatorColumn(name="discr", type="string")
* #DiscriminatorMap({"product" = "Product", "model" = "Model"})
*/
class Product
{
/**
* #ORM\Column(type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
protected $id;
/**
* #var string
* #ORM\Column(type="string", length=100, nullable=false)
*/
protected $name;
...
}
/**
* #ORM\Entity
* #ORM\Table(name="product")
*/
class Model extends Product
{
// Custom properties
...
}
Now you can query the Product entity and it will return the result from all entities that inherits it.