Laravel : Combine two tables using Model relations-CodePudding

i have two tables :: shops and attachments . Shops has all the details for shop and attachments with all the pictures for shop with ref_id as FK .

now for mobile app i have to list shops with Shop title and one image. I can achieve it using leftjoin as below.

Shop::select('shops.name as shop_name','attachments.name as picture')
            ->leftjoin('attachments','attachments.ref_id','=','shops.shop_id')
            ->paginate(10);

This returns just shop name and pictures , I want to achieve same results using relationships that i am not sure of how can i do that. Can someone please advise me on that

Edit

Shop Model

public function attachments(){
     return $this->hasMany(Attachment::class, 'ref_id', 'shop_id');
}

 dd(Shop::find(34)->attachments()->first());
 dd(Shop::with('attachments')->get());

using first dd returns me attachment associated with 34 and but with query is not working and returns just shop

CodePudding user response：

First of all, add the attachments relationship function to the Shop model.

class Shop 
{
    ...

    public function attachments()
    {
        return $this->hasMany(Attachment::class, 'ref_id', 'shop_id');
    }
}

Then you can access shop attachments by using the ->attachments() on the Shop objects.

Example for getting all with pagination: (eager loading)

$shops = Shop::with('attachments')->paginate(10);

# access to first attachment of first shop
$shops->first()->attachments->first()->name

Note: It's better to use eager loading when you want to access all shops attachments to prevent the N 1 query problem

CodePudding user response：

I guess you have to define a One to Many relation in your Shop model (because one shop can have multiple attachements).

Maybe something like this :

// In Shop model

public function attachments()
{
   return $this->hasMany(Attachment::class, 'ref_id', 'shop_id');
}

Then you can use it like this (you don't have to use the find, you can use a where if you want) :

$attachment = Shop::find(1)->attachments()->first();

https://laravel.com/docs/9.x/eloquent-relationships#one-to-many