how to fetch data from 3 different table in laravel using advance join - laravel

Question

I have 3 table
This is my first table cart_items .👇🏻
This is my second table ecomm_products.👇🏻
This is my Third table ecomm_sellers.👇🏻
$result = DB::table('cart_items')
->join('ecomm_products','ecomm_sellers',function($join){
$join->on('ecomm_products.id','=','cart_items.product_id')->where('cart_items.order_id','=',1);
$join->on('ecomm_products.seller_id','=','ecomm_sellers.id');
})
->where('cart_items.user_id','=',Auth::user()->id)
->select('ecomm_products.product_name','ecomm_products.showcase_image','ecomm_products.selling_price','cart_items.quantity','cart_items.id')
->get();
But I am getting an error ⛔⛔⛔
strtolower(): Argument #1 ($string) must be of type string, Closure given
When I have not included 3 tables (ecomm_sellers) till the query is running good but when I add it sends me some errors.
The question is: Why I am getting this error and why this query is not working, What else I can add so that my query working fine.

Answer 1

You cannot join two tables in by passing the table names as arguments to join. If you check the API documentation of the join method you can see that its signature is:
$this join(string $table, Closure|string $first, string|null $operator = null, string|null $second = null, string $type = 'inner', bool $where = false)
so you can only join two tables at a time and if you want to join more than two tables you chain another call to the join method.
try this:
$result = DB::table('cart_items')
->join('ecomm_products', 'ecomm_products.id', '=', 'cart_items.product_id')
->join('ecomm_sellers' , 'ecomm_products.seller_id', '=', 'ecomm_sellers.id')
->where('cart_items.order_id', '=', 1)
->where('cart_items.user_id', '=', Auth::user()->id)
->select([
'ecomm_products.product_name',
'ecomm_products.showcase_image',
'ecomm_products.selling_price',
'cart_items.quantity',
'cart_items.id'
])
->get();
You can find examples for Laravel query builder joins here