Laravel 4关系排序一对多计数急切加载

不确定这是否可能。我可以对当前表艺术家(标题，身体等)内的所有内容进行排序，但还没有弄清楚如何将其排序到与之相关的表。我想根据他/她拥有DESC, ASC的歌曲总数对艺术家进行排序。

如何动态排序来自艺术家的歌曲总数?

管理/艺术家? sortby = songs&订单= asc

artists: id, name, body, slug

songs: id, title, body, slug, hits, artist_id

在此之前，我在控制器中使用了eager loading, Artist::with('songs)…然后在视图中，我可以在foreach循环中使用count($artist->songs)表示歌曲总数。然后我找到了一个更干净的方法http://laravel.io/forum/05 - 03 - 2014 -口才得到数关系

艺术家模型

public function songs()
    {
        return $this->hasMany('Song');
    }
public function songsCountRelation()
{
    return $this->hasOne('Song')->selectRaw('artist_id, count("id") as count')->groupBy('artist_id');
}
public function getSongsCountAttribute()
{
    return $this->songsCountRelation->count;
}

歌模型

public function artist()
{
    return $this->belongsTo('Artist');
}   

public function index()
{
    // Sortby and order variables from url 
    $this->data['sortby'] = Input::get('sortby');
    $this->data['order'] = Input::get('order');
    // If the sortby and order exists in url, fetch the data and order it accordingly
    if ($this->data['sortby'] && $this->data['order'])
    {
        // Order the data based on keys from url
        $this->data['artists'] = Artist::with('songsCountRelation')->orderBy($this->data['sortby'], $this->data['order'])->get(['id', 'name', 'body', 'slug']);
    }
    else
    {
        $this->data['artists'] = Artist::with('songsCountRelation')->get(['id', 'name', 'body', 'slug']);
    }
    $this->layout->content = View::make('admin.artists.index', $this->data);
}

<th>
    {{--Sort by slug--}}
    @if ($sortby == 'slug' && $order == 'asc')
        {{ link_to_route('admin.artists.index', 'Slug', ['sortby' => 'slug', 'order' => 'desc']) }}
    @else
        {{ link_to_route('admin.artists.index', 'Slug', ['sortby' => 'slug', 'order' => 'asc']) }}
    @endif
</th>
<th>
    {{--Sort by total songs--}}
    @if ($sortby == 'songs' && $order == 'asc')
        {{ link_to_route('admin.artists.index', 'Songs', ['sortby' => 'songs', 'order' => 'desc']) }}
    @else
        {{ link_to_route('admin.artists.index', 'Songs', ['sortby' => 'songs', 'order' => 'asc']) }}
    @endif
</th>
...¨
@foreach($artists as $artist)
    <tr>
...
        <td>{{ $artist->songsCount; }}</td>
...     
    </tr>
@endforeach

提前感谢!