How can I combine two tables with my Eloquent query? - php

Question

We work on a database where table names are named locally.
table.product
-- id
-- picture
-- category_id
table.category
-- id
-- caterory_name
-- category_directory
There are some products in table. product.category_id should point category.id so system will understand that product belongs to desired table.
We could do this by using INNER JOIN but we can't do it with Laravel. We probably need to configure our models with has/belongs_to etc.
This is where we struggle.
//Controller
$products = Product::all();
return View::make('theme-admin.product_list')
->with('products', $products);
//View (in foreach)
{{ URL::to('uploads/categories/[NEED_CATEGORY.CATEGORY_DIRECTORY_HERE]/' . $products[$k]->picture) }}
We can't get Category.category_directory info in our views since we pass Product::all() only.
How can we make it so the $products array also contains category.category_directory for each value and we can access it like; $products[$k]->category_name?
Thanks!

Answer 1

Create a category relation in your Product model:
class Product extends Eloquent {
private $table = 'myProductsTableName';
public function category()
{
return $this->belongsTo('Category', 'myCategoryColumnID');
}
}
class Category extends Eloquent {
private $table = 'myCategoriesTableName';
}
Unless you need to select all products from a particular category, you don't need to create a hasMany relation on your Category model.
And you just need to use myCategoryColumnID if your products table doesn't follow the singular_table_name_id rule (product_id).
Then just use it:
//View (in foreach)
{{ URL::to('uploads/categories/'.$products[$k]->category->category_directory.'/' . $products[$k]->picture) }}

Answer 2

I would setup a relationship...
class Product extends Eloquent {
public function category()
{
return $this->belongsTo('Category');
}
}
class Category extends Eloquent {
public function product()
{
return $this->hasMany('Product');
}
}
The name you use in the realtionship is the Model name.....so be sure if you're using a different table name than your model name, that you set that in your model
protected $table = "yourtablename";
Then use it like so...
{{ URL::to('uploads/categories/'.$products[$k]->category->category_directory.'/'
You still end up querying the database multiple times this way... This is called the N+1 effect. Example, if you have 5 products, one query will be executed to get those products. Then in the loop we are executing a query to get the category. This results in 6 total queries.
To solve this problem, use eager loading, which reduces those 6 queries in our example down to 2.
$products = Product::with('category')->get();
Then send that to your view, where you can do your foreach loop..
foreach($products as $val){
//To output the directory
echo $val->category->category_directory;
}
Or in blade...
#foreach($products as $val)
{{URL::to('uploads/categories/'.$val->category->category_directory.'/'.$val->picture)}}
#endfor