Laravel 三向多对多 Eloquent 关系

Question

我有这样的数据库
accounts

id
名字

contacts
- 编号
- account_id
account_communications
- 编号
- account_id

并联系模型：

class Contact extends Model
{ 
    public function Account()
    {
       return $this->belongsTo('App\Account');
    }
   public function AccountCommunication()
   {
      return $this->hasManyThrough( 'App\AccountCommunication','App\Account');
   }
}

账户模型

 class Account extends Model
 {
     public function AccountCommunication()
      {
          return $this->hasMany('App\AccountCommunication');
      } 
    public function Contact()
    {
        return $this->hasMany('App\Contact');
     }
 }

AccountCommunication 模型

class AccountCommunication extends Model
 {
      public function Account()
     {
          return $this->belongsToMany('App\Account');
      }
  }

在我的控制器上

class ContactController extends Controller
  {
     public function index()
     {
        $contacts = Contact::with('Account')->with('AccountCommunication')->paginate(10);
      dd($contacts);
     }
  }

告诉我这个错误

SQLSTATE[42S22]: Column not found: 1054 Unknown column 'accounts.contact_id' in 'field list' (SQL: select account_communications.*, accounts.contact_id from account_communications inner join accounts on accounts.id = account_communications.account_id where accounts.contact_id in (20))

Answer 1

我觉得你误解了HasManyThrough的关系，把它和hasMany混在一起了。如果您只看一眼 laravel HasManyThrough 示例，您会更好地了解它的实际用途

countries
  id - integer
  name - string

users
    id - integer
    country_id - integer --> here is the key role for countries posts
    name - string

posts
    id - integer
    user_id - integer
    title - string

由于您的结构与其用途大不相同。两边都有account_id，还等什么呢？

只需通过 account_id e.x

映射它们

class Contact extends Model
{ 
    public function Account()
    {
       return $this->belongsTo('App\Account');
    }
   public function AccountCommunication()
   {
      return $this->hasMany( 'App\AccountCommunication', 'account_id', 'account_id');
   }
}

Laravel 三向多对多 Eloquent 关系

Laravel Three-way Many-to-Many Eloquent Relationship

php

laravel

eloquent

laravel-5

laravel-eloquent