Load table values into objects variable without mapping - php

Question

I have the following data model
Product: id, description, price
ProductExtraField: id, name
ProductExtraFieldData: product_id, extra_field_id, value
I want to use this datamodel so users of my application can add extra properties to a product on the fly. Let's say the add the property 'Color'. When they do so a row will be created in the ProductExtraField table with a value like this: 6, 'Color'. Now the can add values for this property to there products. When the do so a new row will be created in the ProductExtraFieldData table with a value like this: 4, 6, 'Green'. Now I want to represent this model in a class called Product. I use the following code:
<?php
use Doctrine\Common\Collections\ArrayCollection;
/** #Entity #Table(name="product") **/
class Product
public function __construct() {
$this->extraFieldData = new ArrayCollection();
$this->extraField = new ArrayCollection();
}
/** #Id #Column(name="id", type="integer") #GeneratedValue **/
private $id;
/** #Column(name="description", type="string") **/
private $description;
/** #Column(name="price", type="float") **/
private $price;
/**
* #OneToMany(targetEntity="ProductExtraFieldData", mappedBy="product", cascade={"persist"})
* #JoinColumn(name="product_id", referencedColumnName="id")
* #var extraFieldData[]
**/
protected $extraFieldData = null;
/**
* #OneToMany(targetEntity="ProductExtraField", mappedBy="??????")
* #var extraField[]
**/
protected $extraField = null;
Offcourse the last couple of lines are not correct. I don't know how to load this data. I want the names of the extra fields to be available with every product. I think $extraField should even be static. How can I configure Doctrine to load these values? Persisting the $extraField values from the Product class is not requirement.

Answer 1

Perhaps a structure like the following:
Product
id
description
etc...
ProductExtraField
product_id
extra_field_id
value
ExtraField
id
label
(anything else? type?)
So your Product will have a OneToMany mapping on ProductExtraField, which will have a ManyToOne mapping to ExtraField. Allowing you to use code such as...
$extraValues = array();
foreach ($product->getExtraFields() as $productExtraField) {
$extraValues[$productExtraField->getExtraField()->getLabel()] = $productExtraField->getValue();
}
// builds array such as array('colour' => 'blue', 'size' => 'small)