How to use orderBy using laravel relationship?

Question

Let's say we have a Post model and a Comment model. The Comment model has a belongsTo() relationship with the Post, while the Post has a hasMany() relationship with the comment. I am using the code Post::orderBy('comments_count')->get(); but not working.

Answer 1

in the model you would have:

public function scopecountDescending($query)
{
    return $query->orderBy('comments_count','DESC');
  }  

And in your controller:

 $posts = Post::countDescending()->get();

or simply in your controller:

Post::orderBy('comments_count' , 'DESC')->get();