带有额外字段的 Laravel PIVOT 表

Question

我的数据库中有以下结构。

users
--
id
...

products
--
id
...

licenses (pivot table with some extra informations these data are grabbed via API)
--
user_id
product_id
license_key
license_type
url
purchased_at (datetime)
supported_until (datetime)
...

这是我模型中的代码：

# User has many licenses
# User has many products through licenses
User
  // User has many licenses.
  public function licenses()
  {
    return $this->hasMany(License::class);
  }
  
  // User has many products
  // Expected: products
  // Outcome: not getting
  public function products()
  {
     return $this->belongsToMany(Product::class, 'licenses', 'user_id', 'product_id')
            ->using(License::class);
  }

产品型号。

# Product has many licenses
Product
  
  public function licenses()
  {
    return $this-hasMany(License::class);
  }

许可模式

# License belongs to an user.
# License belongs to a product.
License

  public function user()
  {
    return $this->belongsTo(User::class);
  }
  
  public function product()
  {
    return $this->belongsTo(Product::class);
  }
  

路线

// 导入这些类命名空间并应用所有必要的中间件。 Route::get('/my-products', [ProductController::class, 'index']);

在产品控制器中

ProductController

  public function index()
  {
    $user = Auth::user();
    
    // This doesn't get any products. Which is what I want to use.
    $products = $user->products;
    
    // This works but I want to display more efficiently and using less DB query. 
    $licenses = $user->licenses;
    $products = [];
    foreach ($licenses as $license) {
        array_push( $products, $license->product)
    }
    
    // Get unique products of an user through licenses relation.
    $products = collect($products)->unique();
  }

使用$user->products 时，我没有从许可关系中获得任何产品 如果页面中有超过 5 个产品，我想对产品进行分页，并减少额外的数据库查询和模型加载层。请建议一些更好的方法。

Answer 1

我建议通过许可对属于用户的产品执行单独的单一查询

$products = Product::whereHas('licenses.user', function (Builder $query) use($user) {
                       $query->where('id', $user->id);
                     })->paginate(5);

或

$products = Product::whereHas('licenses', function (Builder $query) use($user) {
                       $query->where('user_id', $user->id);
                     })->paginate(5);

这样，您不必遍历所有数据来从延迟加载的关系中提取产品，也不需要独特的操作