Set up many to many relationship in laravel eloquent

Question

What is the best practice to setup many to many relationship with post and categories in laravel eloquent? Do I create a separate model for pivot table?

This is how I de

Answer 1

The best way to do this is:

public function categories(){
   return $this->belongsToMany('App\Models\Categories', 'categories_posts', 'post_id', 'category_id');
}

And then in your Categories model:

public function posts(){
       return $this->belongsToMany('App\Models\Posts', 'categories_posts', 'category_id', 'post_id');
    }

belongsToMany() method can receive up to 4 parameters, the first one is the location of your model to link, the second is the name of the pivot table, the third one is the current model foreign key and the fourth one is the other's model foreign key.

You can also specify extra data on pivot table using the withPivot() method like this for example:

public function categories(){
       return $this->belongsToMany('App\Models\Categories', 'categories_posts', 'post_id', 'category_id')->withPivot('quantity');
    }

And then for attaching you can do as follows:

$post = Posts:find(1);
$post->categories()->attach($category_id, ['quantity' => 2]);

But please, refer to Laravel's official documentation:

https://laravel.com/docs/5.6/eloquent-relationships