多个表的Laravel Eloquent关系问题
In Laravel 5.5 I try to create a small application to manage products of a couple of sellers/stores.
Therefore, I have four different models like this:
Seller.php
class Attribute extends Model
{
public function items()
{
return $this->belongsToMany(Item::class);
}
}
Item.php
class Item extends Model
{
public function seller()
{
return $this->belongsTo(Seller::class);
}
public function category()
{
return $this->belongsTo(Category::class);
}
public function attributes()
{
return $this->belongsToMany(Item::class);
}
}
Category.php
class Category extends Model
{
public function items()
{
return $this->hasMany(Item::class);
}
}
Attribute.php
class Attribute extends Model
{
public function items()
{
return $this->belongsToMany(Item::class);
}
}
For the many-to-many relation between Attributes & Items, I created a pivot table:
Schema::create('attribute_item', function (Blueprint $table) {
$table->integer('attribute_id')->unsigned()->index();
$table->foreign('attribute_id')->references('id')->on('attributes')->onDelete('cascade');
$table->integer('item_id')->unsigned()->index();
$table->foreign('item_id')->references('id')->on('items')->onDelete('cascade');
$table->primary(['attribute_id', 'item_id']);
});
The goal of the entire application is to:
- fetch all items of a seller by category with attributes (for filtering or something)
- Fetch a specific item of an seller and get its attributes and category
I'm a little bit confused by Laravels relationhip methods and which one to use in that case.
May it is better to hasManyThrough or polymorphic relationhips?
I have to admit that I have a little logic problem here. Hopefully you can help me.
Thank you!
在Laravel 5.5中，我尝试创建一个小应用程序来管理几个卖家/商店的产品。 p >
因此，我有四种不同的模型： p>
Seller.php p>
class Attribute extends Model
{
公共函数项目（）
{
返回$ this-＆gt; belongsToMany（Item :: class）;
}
}
code> pre> \ n
Item.php p>
class Item extends Model
{
public function seller（）
{
返回$ this- ＆gt; belongsTo（Seller :: class）;
}
公共函数类别（）
{
返回$ this-＆gt; belongsTo（Category :: class）;
}
public function attributes（）
{
返回$ this-＆gt; belongsToMany（Item :: class）;
}
}
code> pre>
类别 .php p>
类类别扩展Model
{
公共函数项目（）
{
返回$ this-＆gt; hasMany（Item :: class）;
}
}
code> pre>
Attribute.php p>
class属性扩展Model
{
公共函数项（）
{
返回$ this-＆gt; belongsToMany（Item :: class）;
}
}
code> pre>
对于属性和属性之间的多对多关系 项目，我创建了一个数据透视表： p>
Schema :: create（'attribute_item'，function（Blueprint $ table）{
$ table-＆gt; integer（'attribute_id'） ） - ＆gt; unsigned（） - ＆gt; index（）;
$ table-＆gt; foreign（'attribute_id'） - ＆gt; references（'id'） - ＆gt; on（'attributes'） - ＆gt; onDelete（ 'cascade'）;
$ table-＆gt;整数（'item_id'） - ＆gt; unsigned（） - ＆gt; index（）;
$ table-＆gt; foreign（'item_id'） - ＆gt; references（' id'） - ＆gt; on（'items'） - ＆gt; onDelete（'cascade'）;
$ table-＆gt; primary（['attribute_id'，'item_id']）;
}）;
pre>
整个申请的目标是： p>
- 按类别提取卖家的所有商品（ li>
- 获取卖家的特定商品并获取其属性和类别 li>
ul>
我有一点点 Laravels关系方法和在这种情况下使用的方法相混淆。 p>
hasManyThrough code>或多态关系可能更好吗？ p>
我必须承认我有一点兴趣 这里有gic问题。 希望你能帮帮我。 p>
谢谢！ p>
div>
You can use whereHas method to find the nested relationship let's for example your first goal
fetch all items from a seller by category with attributes (for filtering or something)
You may write the following:
$items = Item::whereHas('seller.items', function ($query) {
$query->whereHas('categories', function ($categories) {
$categories->where('name', '=', 'Mens');
})
->orWhereHas('attributes', function ($attributes) {
$attriutes->where('size', '=', 'large');
});
})->get();
Find out more about this: https://laravel.com/docs/5.5/eloquent-relationships#querying-relationship-existence
This will give you the list of items if you want to get items with categories and attributes you can use with method to get the relational data:
$items = Item::whereHas('seller.items', function ($query) {
$query->whereHas('categories', function ($caegories) {
$categories->where('name', '=', 'Mens');
})
->orWhereHas('attributes', function ($attributes) {
$atributes->where('size', '=', 'large');
});
})
->with('categories', 'attributes')
->get();
Hope this guide you the problem which you are facing.