laravel 5从关系

Question

我试图通过关系获得平均值

我正在做的是：

$user_detail=Users::withCount('followers')->withCount('followings')->withCount('posts')->with('ratings')->with('posts')->where('user_id',$user_id)->get();

public function ratings()
{
    return $this->hasMany('\App\Reviews','review_user_id','user_id')->selectRaw('review_user_id, avg(rate) AS avg')->groupBy('review_user_id');
}

现在这是有效的，我得到的是：

"followers_count": 0,
"followings_count": 1,
"posts_count": 1,
"ratings": [
      {
        "review_user_id": "2c61d7a0-7d05-11e7-8dab-6d6ba8a72982",
        "avg": 3.25
      }
    ],

我想要的是：

"ratings": 3.25

任何帮助都将不胜感激。

PS：Laravel 5.2

Answer 1

这应该这样做

return $this->hasMany('\App\Reviews','review_user_id','user_id')->
selectRaw('review_user_id, avg(rate) AS avg')->
groupBy('review_user_id')
->pluck('avg');