Can I use Laravel's eloquent hasManyThrough relationship for my specific case?

Question

I'm trying to retrieve data from a table that I don't have a direct relationship with from the model I am currently using.

My data structure:

Table: posts

• id - integer
• title - string

---

Table: post_stacks

• id - integer
• post_id - integer
• stack_id - integer

---

Table: stacks

• id - integer
• body - string
• url - string

---

My eloquent model is from the Post.php (posts table) and i'm trying to get all the stacks associated to my post (from the stacks table). I want to declare my relationships only on Post.php and not my pivot table (post_stacks). I tried using hasManyThrough but i can't get it to work?

public function img()
    {
        return $this->hasManyThrough(\App\Stack::class, \App\PostStack::class, 'post_id', 'stack_id', 'id');
    }

Would anyone know how i can retrieve my desired data? Thanks!

Answer 1

Can you try to put below relationships on your posts model.

public function stacks()
{
    return $this->hasManyThrough(
        'App\Stacks', 'App\PostStacks',
        'post_id', 'id', 'id'
    );
}

Also have a look at this, https://laravel.com/docs/5.4/eloquent-relationships#has-many-through

According to this doc, The third argument in hasManyThrough is the name of the foreign key on the intermediate model. In our case 'post_id' is the foreign key on post_stack that has direct relation to posts .

Fourth argument is the name of the foreign key on the final model. ie, 'id' on stacks . that has relationship to post_stacks ( 'post_id' ) . Fifth argument is the local key. ie, id of posts