Eloquent 模型关系不返回子关系特定的列值

Question

当产品名称等于“糟糕”时，我试图实现拉取用户信息和产品详细信息（指定昵称和名称），但我不知道为什么 getProducts 不返回任何东西。

用户模型

 public function getProducts(){
        return $this->hasMany('App\Models\Product','users_id');
    }

产品型号

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

拉取数据的代码：

$products = User::with(['getProducts' => function($query){
            $query->select("users_id","name","nickname");
        }])->get();

当前输出：

"data": [
    {
      "id": 1,
      "name": "John Smith",
      "email": "john.smith@hotmail.com",
      "email_verified_at": null,
      "created_at": "2021-04-08T13:29:13.000000Z",
      "updated_at": "2021-04-08T13:29:13.000000Z",
      "role": 0,
      "get_products": [
        
      ]
    },
    {
      "id": 2,
      "name": "Kelvin Ooi",
      "email": "kelvin.ooi@hotmail.com",
      "email_verified_at": null,
      "created_at": "2021-04-08T13:29:13.000000Z",
      "updated_at": "2021-04-13T12:07:11.000000Z",
      "role": 1,
      "get_products": [
            {
                "nickname":"MCD",
                "name":"Oops"
            },
            {
                "nickname":"Mary Brown",
                "name":"Oops"
            },
            {
                "nickname":"Kentucy",
                "name":"KFC"
            },
            {
                "nickname":"Texas Chicken",
                "name":"TXS"
            }            
      ]
    }
  ]

预期输出

"data": [
    {
      "id": 1,
      "name": "John Smith",
      "email": "john.smith@hotmail.com",
      "email_verified_at": null,
      "created_at": "2021-04-08T13:29:13.000000Z",
      "updated_at": "2021-04-08T13:29:13.000000Z",
      "role": 0,
      "get_products": [
        
      ]
    },
    {
      "id": 2,
      "name": "Kelvin Ooi",
      "email": "kelvin.ooi@hotmail.com",
      "email_verified_at": null,
      "created_at": "2021-04-08T13:29:13.000000Z",
      "updated_at": "2021-04-13T12:07:11.000000Z",
      "role": 1,
      "get_products": [
            {
                "nickname":"MCD",
                "name":"Oops"
            },
            {
                "nickname":"Mary Brown",
                "name":"Oops"
            }
      ]
    }
  ]

Answer 1

getProducts 不是一个好的关系名称，我们直接称它为products。

public function products()
{
    return $this->hasMany('App\Models\Product','users_id');
}

注释中的代码不起作用，因为您在主查询中指定了 where 子句，而不是子查询。

return User::with(['products' => function ($query) { 
    $query->select("users_id","name","nickname"); 
}])
// This got to be in the sub query.
->where("products.name","Oops")
->get();

所以让我们将您的代码更新为：

$productName = 'Oops';

return User::with(['products' => function ($query) use ($productName) { 
    $query->select("users_id","name","nickname", "price")
        ->where("name","LIKE", "%{$productName}%"); 
}])
->get();

我已经看到您对此答案的评论。让我们为 User 模型定义一个 total custom attribute：

class User extends Model
{
    protected $appends = ['total'];

    public function getTotalAttribute()
    {
        // This is higher order message, if you haven't used it: https://laravel.com/docs/8.x/collections#higher-order-messages
        return $this->products->sum->price;
    }
}

那么total 属性将成为任何用户的一部分。