sql - Laravel Eloquent ORM "whereHas"通过表

Question

嘿，我的网站Phones number lookup上的Laravel有问题。我尝试通过联系表选择具有我选择的城市的地方。

我的模型课:
地方类(class):

class Places extends Eloquent {
    public function contacts()
    {
        return $this->hasOne('Contacts');
    }
     public function clubs()
     {
        return $this->hasOne('Clubs');
     }    
}

联系人类别:

 class Contacts extends Eloquent {
     public function cities()
     {
         return $this->hasOne('Cities');
     }
   }

城市类别:

 class Cities extends Eloquent {

 }

我的查询:

$view->clubs = Places::whereHas('contacts',function ($q) use($city_id){
           $q->where('contacts', function ($q) use($city_id){
               $q->where('id', $city_id);
            });
        })->get();

错误消息:

MySQL server version for the right syntax to use near 'where id = ?)) >= 1' at line 1 (SQL: select * from places where (select count(*) from contacts where contacts.places_id = places.id and contacts = (select * where id = 2223)) >= 1)

我知道它缺少“from” citites，但是我不知道如何实现。

Answer 1

您有3个使用关系的选项:

1个最简单的解决方案:

Places::whereHas('contacts',function ($q) use ($city_id){
       $q->whereHas('cities', function ($q) use ($city_id){
           $q->where('id', $city_id);
        });
    })->get();

2与上面相同，但使用此PR:https://github.com/laravel/framework/pull/4954

Places::whereHas('contacts.cities', function ($q) use ($city_id){
        $q->where('id', $city_id);   
    })->get();

3使用hasManyThrough关系:

// Place model
public function cities()
{
  return $this->hasManyThrough('City', 'Contact');
}

// then
Places::whereHas('cities',function ($q) use ($city_id){
   $q->where('cities.id', $city_id);
})->get();

编辑

有了您的架构，很明显，所有建议或原始设置都无法正常工作。

这是一个多对多的关系，在Eloquent中是belongsToMany:

// Places model
public function cities()
{
  return $this->belongsToMany('Cities', 'contacts', 'places_id', 'cities_id')
    ->withPivot( .. contacts table fields that you need go here.. );
}

// Cities model
public function places()
{
  return $this->belongsToMany('Places', 'contacts', 'cities_id', 'places_id')
    ->withPivot( .. contacts table fields that you need go here.. );
}

然后，您可以像这样调用关系:

$city = Cities::first();
$city->places; // collection of Places models

// contacts data for a single city-place pair
$city->places->first()->pivot->open_hours; // or whatever you include in withPivot above

现在，还有另一种设置方法，以防您还需要Contacts模型本身:

// Places model
public function contact()
{
  return $this->hasOne('Contacts', 'places_id');
}

// Contacts model
public function city()
{
  return $this->belongsTo('Cities', 'cities_id');
}

public function place()
{
  return $this->belongsTo('Places', 'places_id');
}

// Cities model
public function contact()
{
  return $this->hasOne('Contacts', 'cities_id');
}

然后:

$city = Cities::first();
$city->contact; // Contacts model
$city->contact->place; // Places model

hasManyThrough在这里根本无法使用