Question

我有一个关于Laravel口才的问题。

数据库表

类别：id root_id名称

产品ID名称等。

product_categories id product_id category_id

因此它可能是具有子类别B的CategoryA，而类别B本身具有子类别C。

当我单击CategoryA时，我想查找属于CategoryA，CategoryB，CategoryC的所有产品

Category Model

   public function cats()
    {
        return $this->hasMany(Category::class);
    }


    public function childrenCategories()
    {
        return $this->hasMany(Category::class)->with('cats');
    }

产品型号

public function categories()
    {
        return $this->belongsToMany(Category::class);
    }

控制器

//首先，我得到所有类别的所有ID，所有级别的子类别。

        $categories = Category::where('category_id',$category_id)->with('childrenCategories')->get();
        $all_cat_array=array();$all_prod=array();

foreach ($categories as $category)
{
    foreach ($category->childrenCategories as $childCategory) {
        array_push($all_cat_array, $childCategory->id);
    }
    array_push($all_cat_array,$category->id);

}

//然后我得到了产品的所有ID

foreach ($all_cat_array as $cat)
{
    if(CategoryProduct::where('category_id',$cat)->exists()) {
        $prod=CategoryProduct::where('category_id',$cat)->pluck('product_id');
        array_push($all_prod,$prod );
    }
}

但是我不想使用所有这些foreach，因为我想优化代码。我可以做些什么来简化它？

Answer 1

有关更多信息，请阅读Laravel Docs

数据库

类别数据库

Schema::create('category_as', function (Blueprint $table) {
  $table->bigIncrements('id');
  $table->unsignedBigInteger('product_id');
  ...
  $table->timestamps();

  $table->foreign('product_id')->references('id')->on('products')->onDelete('cascade');
});

类别B数据库

Schema::create('category_bs', function (Blueprint $table) {
  $table->bigIncrements('id');
  $table->unsignedBigInteger('category_a_id');
  ...
  $table->timestamps();

  $table->foreign('category_a_id')->references('id')->on('category_as')->onDelete('cascade');
});

模型

产品型号

public function categories_a() {
  return $this->hasmany(Category_a::class);
}

类别A模型

public function categories_b() {
  return $this->hasmany(Category_b::class);
}

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

B类模型

public function category_a() {
  return $this->belongsTo(Category_a::class);
}

public function clients() {
   return $this->hasManyThrough(Client::class, Code::class);
}

CONTROLLER

public function index() {
  $products = Product::all();
  $query = $products->categories_a->categories_b;
  dd($query);
}

已编辑

数据库

类别数据库

Schema::create('categories', function (Blueprint $table) {
  $table->bigIncrements('id');
  $table->unsignedBigInteger('product_id');
  ...
  $table->timestamps();

  $table->foreign('product_id')->references('id')->on('products')->onDelete('cascade');
});

模型

产品型号

public function categories() {
  return $this->hasmany(Category::class);
}

类别模型

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

CONTROLLER

public function index() {
  $products = Product::all();
  $query = $products->categories;
  dd($query);
}

Answer 2

我建议您在类别模型中使用嵌套集结构。

此软件包https://github.com/lazychaser/laravel-nestedset中的实现很好。

通过2个查询，您可以获得类别及其所有后代的产品（具有无限嵌套）。

如果类别属于许多产品：

$categoryIds = Category::descendantsAndSelf($categoryId)->pluck('id');

$products = Product::whereHas('categories', function ($query) use ($categoryIds) {
    $query->whereIn('categories.id', $categoryIds);
});

如果类别中有很多产品

$categoryIds = Category::descendantsAndSelf($categoryId)->pluck('id');

$products = Product::whereIn('category_id', $categoryIds);

Laravel雄辩地与类别

2 个答案: