Laravel关联模型

1.多对多关联.如收藏.用户表users，产品表products，收藏中间表user_favorite_products.那么在用户模型下则

    public function favoriteProducts()
    {
        return $this->belongsToMany(Product::class, 'user_favorite_products')
            ->withTimestamps() //中间表时间
            ->orderBy('user_favorite_products.created_at', 'desc');
    }

收藏关联新增

    public function favor(Product $product, Request $request)
    {
        $user = $request->user();
        if ($user->favoriteProducts()->find($product->id)) {
            return [];
        }

        $user->favoriteProducts()->attach($product);

        return [];
    }

示例2：关联新增加时，附加新增其它数据

$user = App\User::find(1);

$user->roles()->attach($roleId);
//增加一个过期时间字段
$user->roles()->attach($roleId, ['expires' => $expires]);