Laravel relations doesn't return anything

Question

i have problem in laravel eloquent relationships. there is 2 model in my application: article and category.

article model:

public function category()
{
    return $this->belongsToMany('App\Category');
}

category model:

public function article()
{
    return $this->hasMany('App\Article');
}

the relation between this tow is hasMany (Category -> article) & belongsToMany (Article -> category) .

category will fetch by requested slug using this method at categoryController:

$category = Category::where('slug', '=', $slug)->get();

problem will be shown in view when i want to fetch articles from category and nothhing will return back:

@foreach ($category->article->all() as $article)
    {{ $article->name }}
@endforeach

and from @dd($category->article) we will get empty collection:

Collection {#323 ▼
  #items: []
}

Answer 1

As @lagbox tried to highlight in a comment, for pivot tables, both relationships should be belongsToMany . Inverse of hasMany is belongsTo .

If one article belongs to many categories, and one category can have many articles, then, ideally, there it should be a many-to-many relationship. Category model should have a belongsToMany relationship with Article model and vice versa. Additionally, there should be a pivot table, article_category . And as many have suggested, you can get articles the belongs to a category by using @foreach($category->articles as $articles)

You can read more about many to many here: https://laravel.com/docs/5.8/eloquent-relationships#many-to-many

Answer 2

You can use @forelse blade directive like

@forelse ($category->article as $article)
    <li>{{ $article->name }}</li>
@empty
    <p>No articles</p>
@endforelse

You can check that here

Answer 3

You dont need to write $category->article->all() . $category->article itself will return all articles. So just use like,

@foreach ($category->article->all() as $article)
  {{ $article->name }}
@endforeach

For eager loading articles, you can use with keyword

$category = Category::with('article')->where('slug', '=', $slug)->get();

Answer 4

In your controller

$category = Category::with('article')->where('slug',$slug)->get();

In your blade.php file

@foreach($category->article as $article)
    <li>{{ $article->name }}</li>
@endforeach