Laravel RelationShip 选择字段无效

Question

我正在尝试从表之间的关系中获取属性，但它似乎不起作用，我尝试了网络上的其他解决方案但仍然不起作用，这里是我调用的代码：

$data = Employer::with(['contratClient'=>function($query){$query->select("idcontrat");}])
                ->where("id_entre",1)
                ->get();
echo "<pre>";
dd($data[0]->contratClient);
echo "</pre>";

雇主模型：

class Employer extends Model{
    protected $primaryKey = 'id_em';
    protected $table = 'employers';
    protected $guarded = array();

    public function contratClient(){
         return $this->hasMany("App\ContratClient","id_emp");
    }
 }

ContratClient 模型：

class ContratClient extends Model
{
     protected $primaryKey = 'idcontrat';
     protected $table = 'contratClients';

     public function employer(){
         return $this->belongsTo('App\Employer','id_em');
     }
}

结果如下：

如果我遗漏了什么，请列出，我仍然是 Laravel

的初学者

谢谢

Answer 1

我认为您的主键不是 laravel 所需要的。例如：

在 employers table 中，laravel 需要 employer_id 但您的主键是 id_em。请将您的关系更新为以下并再次检查：

class Employer extends Model{
    protected $primaryKey = 'id_em';
    protected $table = 'employers';
    protected $guarded = array();

    public function contratClient(){

         return $this->hasMany('App\ContratClient','foreign_key_in_this_table', 'idcontrat');
    }
 }

class ContratClient extends Model
{
     protected $primaryKey = 'idcontrat';
     protected $table = 'contratClients';

     public function employer(){

         return $this->belongsTo('App\Employer','foreign_key_in_this_table', 'id_em');
     }
}

还要检查它是否是 contratClients 类型，您的意思是 contractClients 吗？

Answer 2

模型关系应该是：

class Employer extends Model{
    protected $primaryKey = 'id_em';
    protected $table = 'employers';
    protected $guarded = array();

    public function contratClient(){
         return $this->hasMany("App\ContratClient","id_emp", "id_em");
    }
}

class ContratClient extends Model
{
     protected $primaryKey = 'idcontrat';
     protected $table = 'contratClients';

     public function employer(){
         return $this->belongsTo('App\Employer','id_emp', 'id_em');
     }
}

要验证关系，首先尝试获取行：

$data = Employer::with('contratClient')->get();

Laravel RelationShip 选择字段无效

Laravel RelationShip Selecting Fileds Not Working

php

laravel

eloquent

laravel-query-builder