Could someone explain the ORM used in current web frameworks?

Question

I'm very new to ORM and I kind of understand the definition. Confusion starts when I try to implement relations.

Suppose I have these two tables.

Products table:

+-------------+--------------+------+-----+---------+----------------+
| Field       | Type         | Null | Key | Default | Extra          |
+-------------+--------------+------+-----+---------+----------------+
| id          | int(11)      | NO   | PRI | NULL    | auto_increment |
| brand_id    | int(11)      | YES  |     | NULL    |                |
| name        | varchar(100) | YES  |     | NULL    |                |
| description | text         | YES  |     | NULL    |                |
+-------------+--------------+------+-----+---------+----------------+

Brand names table:

+------------+--------------+------+-----+---------+----------------+
| Field      | Type         | Null | Key | Default | Extra          |
+------------+--------------+------+-----+---------+----------------+
| id         | int(11)      | NO   | PRI | NULL    | auto_increment |
| name       | varchar(100) | YES  |     | NULL    |                |
+------------+--------------+------+-----+---------+----------------+

How do I set up the models with $_has_many $_belongs_to so that when I do $product1 = Model_Product::find('first'); It also returns the name of the brand, like in SQL joins.

Or am I going about this the wrong way.

This doesn't have to be specific to fuelphp, I just want how to setup ORMs in this case.

Answer 1

In fuelphp you can use ORM simpli define the relation in the model file:

model/brand.php

class Model_Brand extends Orm\Model {

   protected static $_has_many = array(
        'products' => array(
            'model_to' => 'Model_Product',
            'key_from' => 'id',
            'key_to' => 'brand_id',
            'cascade_save' => false,
            'cascade_delete' => true,
        )
    );
}

model/product.php

class Model_Product extends Orm\Model {
    protected static $_belongs_to = array('brand');
}

When you'll perform $brand = Model_Brand::find('first'); you can access list of products with $brand['products']

When you'll perform $product = Model_Product::find('first'); you can access the brand with $product['brand']

Answer 2

An example in a somewhat Rails-ish way would be:

class Brand
  has_many :products
end

class Product
  belongs_to :brand
end

product = Product.first
product.brand
=> <#Brand...>
brand = Brand.first
brand.products
=> [<#Product...>, <#Product...>]

This isn't complete code by any means but hopefully you'll get the idea.