php - 如何用 Eloquent 方式在数据透视表中获取具有特定属性的所有项目？

Question

我的循环表有一个“最喜欢的”功能。我试图通过数据透视表来实现这一点。但现在我正试图找到最有效的方式来 Eloquent 地调用所有登录用户最喜欢的循环。

循环表:

    Schema::create('loops', function(Blueprint $table) {
        $table->increments('id');
        $table->string('name', 35);
        $table->string('loop_path', 255);
        $table->string('FK_user_id');
    });

用户表:

    Schema::create('users', function(Blueprint $table) {
        $table->increments('id');
        $table->string('name');
        $table->string('password', 60);
    });

收藏夹表:

    Schema::create('favourites', function(Blueprint $table) {
        $table->increments('id');
        $table->integer('FK_user_id')->unsigned();
        $table->integer('FK_loop_id')->unsigned();
    });

循环.php :

class Loop extends Model {

    protected $table = 'loops';
    public $timestamps = true;

    public function user()
    {
        return $this->belongsTo('App\User','FK_user_id','id');
    }

    public function favourites()
    {
        return $this->belongsToMany('App\User', 'favourites', 'FK_loop_id', 'FK_user_id');
    }

}

这就是我现在的实现方式，但似乎效率不高:

    $loops = Loop::with('favourites')->
                   with('user')->get();

    $favouritedLoops = array();

    foreach($loops as $loop) 
    {
        //check if logged in user has favourited this
        $user_favorites = Favourite::where('FK_user_id', '=', Auth::user()->id)
            ->where('FK_loop_id', '=', $loop->id)
            ->first();

        if ($user_favorites != null)
        {
            array_push($favouritedLoops, $loop);
        }

    }

    return Response::json($favouritedLoops);

Answer 1

您应该在User 模型中定义favouritedLoops 方法，然后您可以轻松访问所有收藏的循环。

User.php

public function favouritedLoops()
{
    return $this->belongsToMany('App\Loop', 'favourites', 'FK_user_id', 'FK_loop_id');
}

现在返回看起来像:return Response::json(Auth::user()->favouritedLoops);