Doctrine Relationship on a namespaced table - database

Question

I have several doctrine models that have relationships to other models. Let's call those ItemsOne, ItemsTwo, ItemsThree. Each has a relationship defined to the Products doctrine class (products table) and the relationship is defined as:
$this->hasMany(
'Models_Products as Products',
array(
'local' => 'id',
'foreign' => 'product_id',
)
);
Nothing out of the ordinary there.
I also have another table (prices) which stores namespaced data. By that I mean that the particular table stores data based on a predefined key (i.e. Vinyl, CD, DVD) so the rows would show something like this:
media_namespace entity_id quantity unit_price
CD 4 1000 0.99
DVD 4 2500 1.25
CD 7 3750 0.25
Vinyl 15 75 4.25
The entity_id is the id of each of the models accessing this table. So for instance CD/entity_id = 4 refers to ItemsOne model, DVD/entity_id = 4 refers to the ItemsTwo model, etc.
I want to create a relationship - and I don't know if this can be done - whereas it will be namespaced in the model. So in the above snipped for the products relationship I need something like (for the ItemsOne model):
$this->hasMany(
'Models_Prices as Prices',
array(
'local' => 'id',
'foreign' => 'entity_id',
)
);
However the above will return all the prices with the entity_id matching the ItemsOne table which is partly correct. In the above example if entity_id = 4, it will return the CD record but also the DVD one which is not what I need. I want it to be filtering the data based on the media_namespace table. So in short what I need is:
prices.media_namespace = 'CD' AND prices.entity_id = itemsone.id
Can the above be reflected in a hasMany relationship in Doctrine? I have searched and cannot something that would help.
Any pointers are more than appreciated!

Answer 1

You need to use Doctrine subclasses. Create a subclass for each namespace. This will let you reference a specific set of data by class name.
class Models_Price
subclass Models_Price_CD
subclass Models_Price_DVD
subclass Models_Price_Vinyl
In the Price class, you'll need to specify the following:
public function setUp()
{
parent::setUp();
$this->setSubclasses(
array(
'Price_CD' => array(
'media_namespace' => 'CD',
),
'Price_DVD' => array(
'media_namespace' => 'DVD',
),
'Price_Vinyl' => array(
'media_namespace' => 'Vinyl',
),
)
);
}
Let's make the assumption that ItemsOne uses namespace CD, ItemsTwo uses namespace DVD, and ItemsThree uses namespace Vinyl.
For this situation, you would add the following relationship to each class:
ItemsOne:
$this->hasMany(
'Models_Price_CD as Prices',
array(
'local' => 'id',
'foreign' => 'entity_id',
)
);
ItemsTwo:
$this->hasMany(
'Models_Price_DVD as Prices',
array(
'local' => 'id',
'foreign' => 'entity_id',
)
);
ItemsThree:
$this->hasMany(
'Models_Price_Vinyl as Prices',
array(
'local' => 'id',
'foreign' => 'entity_id',
)
);
Now, each of the Prices relations will return only what you expect. Doctrine, seeing the subclass, will automatically namespace all the queries you perform on that table.