如何只显示未应用的类别？

Question

I have categories table and I want to display only the categories which are not available in the business_category table OR the business_category->approved is 2.

My code for that:

<div class="col-md-6">
   <select multiple name="categories[]" id="categories" class="form-control @error('categories') is-invalid @enderror" autofocus required>
        @foreach($categories as $category)
            @foreach($business_categories as $business_category)
               @if(($business_category->approved==2) || ($business_category->category_id != $category->id))
                   <option value="{{$category->id}}">{{$category->name}}</option>
               @endif
            @endforeach
        @endforeach
  </select>
</div>

My Code in Controller:

$business_categories = BusinessCategories::join('categories', 'categories.id', '=', 'category_id')
    ->where('business_id', $id)
    ->select('categories.name as name', 'approved', 'category_id')
    ->get();

$categories = Categories::where('parent_id', '0')->select('id', 'name')->get();

return view('admin.businesses.edit', with([
    'business_categories' => $business_categories,
    'categories'          => $categories,
]));

But this code displays the categories which is applied or not applied multiple times.

Answer 1

First, you need a hasMany businessCategories relationship on Categories model:

public function businessCategories()
{
    return $this->hasMany(BusinessCategories::class);
}

Your query

Categories::orWhereDoesntHave('businessCategories')
    ->orWhereHas('businessCategories', function($query) {
        $query->where('approved', 2);
    })->get();

You can find more eloquent relationship query information here