Laravel Eloquent Model can't sync with pivot data in Many-to-Many relationship

Question

I would like to sync the data instead of attach the data to the particular relationship.

Pivot relation UserModel code

public function carts(){
        return $this->belongsToMany(Product::class,'user_carts')->withPivot('quantity');
    }

The attach code is

User::find(1)->carts()->attach($s,["quantity"=>1]);

The sync code is

User::find(1)->carts()->sync($s,["quantity"=>1]);

When I try to compile the sync, those pivot relation that matched user_id = 1 does not have the "1" in its respective quantity column.

If I would like to achieve the sync function without using attach, how can I do it because the attach() will create multiple redundant data in my database.

I see there is two table `user` and `cart` but how come `product` model. For more details pls https://stackoverflow.com/questions/66811609/cant-insert-into-pivot-table/66812016#66812016 — A.A Noman, Apr 28 '21 at 09:05
The pivot table cart is to connect product and user model together. — Miracle Hades, Apr 28 '21 at 09:07

Daan · Answer 1 · 2021-04-28T08:54:13.390

2

You have to pass key values in the sync method. Assuming $s is the id (key) to be synced:

User::find(1)->carts()->sync([$s => ["quantity"=>1]]);

edited Apr 28 '21 at 08:54

answered Apr 28 '21 at 08:50

Daan

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ErrorException Illegal offset type http://localhost:8000/api/pivot – Miracle Hades Apr 28 '21 at 08:51
I can't help you with just that information. – Daan Apr 28 '21 at 08:53
actually my $s = Product::whereIn("id",[4,10])->get(); – Miracle Hades Apr 28 '21 at 08:58
your solution will work when the $s only return a single id but in my scenario, there will be multiple id will be passed through on the $s. – Miracle Hades Apr 28 '21 at 08:58
So map over `$s` and add `['quantity' => 1]` on every record. – Daan Apr 28 '21 at 09:00
$s = $s->map(function($value){ return [ $value->id => ["quantity"=>1] ]; }); – Miracle Hades Apr 28 '21 at 09:05
ErrorException Array to string conversion – Miracle Hades Apr 28 '21 at 09:05
Modified code: User::find(1)->carts()->sync($s); – Miracle Hades Apr 28 '21 at 09:06
The array structure that it will produce is incorrect, try dumping `$s` after the map. – Daan Apr 28 '21 at 09:10

Laravel Eloquent Model can't sync with pivot data in Many-to-Many relationship

1 Answers1