从多个相关记录中获取一组相关记录laravel？

Question

I have users that have multiple restaurants , then each restaurant has comments .

So when a user logs in, I would like to show a list of all the comments from restaurants related to the user.

I am using laravel 5.1

What I have so far is:

$restaurants = $user->restaurants;
        $comments = null;
        foreach ($restaurants as $restaurant) {
            if (!$comments){
              $comments = $restaurants->comments();
            } else{
              $comments = $comments->merge($restaurant->comments());
            }
        }

        $rows = $comments->paginate(15);
        $count = $comments->count();

I get a BadMethodCallException , I think I am not doing this the laravel way.

Answer 1

Have u tried Have Many Through?
In User model public function user_posts() { return $this->hasManyThrough('App\\Comment', 'App\\Restaurant'); } public function user_posts() { return $this->hasManyThrough('App\\Comment', 'App\\Restaurant'); } And in controller u easily to access comments $comments = $user->user_posts(); More details here: https://laravel.com/docs/5.1/eloquent-relationships#has-many-through

Answer 2

I have just found the answer, to use merge the dataset needs to be a collection .

So to create the collection you need to use: ->get();

In my example:

$comments = $restaurants->comments()->get();

Note: the paginate function has to go, it is nota method of a laravel Collection

Answer 3

You were almost correct, you should have done

$restaurant->comments
// gives you objects

instead of

$restaurant->comments()
// gives you query builder
// $restaurants->comments()->get() would also work as someone mentioned

as for pagination you can do

$restaurants->comments()->paginate(15)

instead of

$restaurants->comments()->get()