Get all posts and check if user liked each post

问题

I'm trying to create an Eloquent query that fetches all posts and checks if the user liked each of those posts.

I have the following models:

Post.php

class Post extends Eloquent {

    /**
     * The database table used by the model.
     *
     * @var string
     */
    protected $table = 'posts';

    public function user()
    {
        return $this->belongsTo('User');
    }

    public function likes()
    {
        return $this->hasMany('Like');
    }
}

Like.php:

class Like extends Eloquent {

    /**
     * The database table used by the model.
     *
     * @var string
     */
    protected $table = 'likes';
}

And your typical User model as well.

My DB structure is the following:

posts table:

+----+---------+---------+
| id | user_id | message |
+----+---------+---------+

users table:

+----+----------+
| id | username |
+----+----------+

likes table:

+----+---------+---------+
| id | post_id | user_id |
+----+---------+---------+

Right now, my query only returns all posts, but how can I modify it to return all posts and check if the user liked each post?

Route::get('/', array('as' => 'index', function()
{
    $posts = Post::all();

    return View::make('index')->with('posts', $posts);
}));

Thanks!

回答1:

What about a left join between the posts table and the likes table, filtering by the actual user's id?

$post = DB::table('post')
                 ->select(DB::raw('message, likes.user_id IS NOT NULL as liked'))
                 ->leftJoin('likes', 'users_id', '=', 'likes.user_id')
                 ->where('likes.user_id', '=', $curent_user_id)  
                 ->get();

I have no way to test it now, but I hope it might give you some inspiration :)

回答2:

You can grab the likes with the post for that specific user. Try this..

Post::with(['likes' => function() use ($user_id) { $q->where('user_id','=', $user_id); }])->all();

It will return blank array if user haven't like the post.

来源：https://stackoverflow.com/questions/31059948/get-all-posts-and-check-if-user-liked-each-post

标签

laravel

laravel-4

eloquent