Laravel realtionship sometimes not functional - php

Question

I have Laravel 5. framework for bacis e-shop, i try use relationship I have Order, Order_item, Product, Customer model
Order model has realationship with
class Order extends Model
{
protected $fillable = ['user_id', 'status'];
protected $dates = ['created_at'];
/**
* Get the items for the order.
*/
public function items()
{
return $this->hasMany('App\Order_item');
}
public function customer()
{
return $this->hasOne('App\Customer','id');
}
}
Order item
class Order_item extends Model
{
protected $fillable = ['order_id', 'product_id', 'quantity', 'price'];
public function product()
{
return $this->hasOne('App\Product','id');
}
}
in controller
public function detail($id)
{
$order = Order::with('customer','items')->findOrFail($id);
return view('admin.detail', ['order' => $order]);
}
and in view I have
<h2>Objednávka č. {{ $order->id }}</h2>
<h3>Zákazník:</h3>
{{ $order->customer->firstname }} {{ $order->customer->lastname }}
<p>{{ $order->customer->email }}</p>
{{ $order->customer->phone }}
<h3>Adresa:</h3>
<p>{{ $order->customer->street }}</p>
<p>{{ $order->customer->city }}</p>
<p>{{ $order->customer->psc }}</p>
<h3>Položky:</h3>
<table class="table table-bordered table-striped">
<thead>
<th>Název</th>
<th>Počet</th>
<th>Cena</th>
</thead>
<tbody>
#foreach($order->items as $item)
<tr>
<th>{{ $item->product->name }}</th>
<th>{{ $item->quantity }}</th>
<th>{{ $item->price }}</th>
</tr>
#endforeach
</tbody>
</table>
and now when i test the code for someone order is function but for someone no, the problem is on {{ $item->product->name }}
is my realationship ok? Its a better solution for my e-shop relationship
i post my complete code to github https://github.com/mardon/MaMushashop

Answer 1

Your order item table is a pivot table. There for the relationships to order and product should be declared as belongsToMany.
belongsToMany is used in Many To Many.
hasMany is used in a One To Many
hasOne is used in One To One
The naming of your table Order_item should be order_product to better reflect what it actually contains.
class order_product extends Model
{
protected $fillable = ['order_id', 'product_id', 'quantity', 'price'];
public function product()
{
return $this->belongsToMany('App\Product', 'order_product', 'order_id', 'product_id);
}
public function order()
{
return $this->belongsToMany('App\Order', 'order_product', 'product_id', 'order_id);
}
}

Answer 2

Do like this
$order = DB::table('order')
->join('customer', 'order.customer_id', '=', 'customer.id')
->select('order.*', 'customer.*')
->where('order.id', '=', $id)
->first();
$order_items = Order_item::where('order_id', $id)->get();
return view('admin.detail', ['order' => $order, 'order_items' => $order_items]);
And generate item like this
#foreach($order_items as $item)
<tr>
<th>{{ $item->product->name }}</th>
<th>{{ $item->quantity }}</th>
<th>{{ $item->price }}</th>
</tr>
#endforeach