Laravel 8 - 2 database connection - leftjoin - database

Question

I've got 2 different databases and need a leftjoin to the second one.
It's on Laravel 8. It's a MariaDB and the sql_erp it's on MSSQL.
Who can help me?
My received fault-message is:
SQLSTATE[42S02]: Base table or view not found: 1146 Table 'sql_erp.artikel_stamm' doesn't exist (SQL: select * from `aa_bom` left join `sql_erp`.`ARTIKEL_STAMM` on `bom`.`art_nr` = `Artikel_Stamm`.`ARTNR` where `_x_zu_aa_doc_steps` = 1 order by `pos` asc limit 99)
in my controller:
<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request;
use App\Models\Arbeitsanw\aa_doc_steps;
use App\Models\Arbeitsanw\aa_doc_header;
use App\Models\Arbeitsanw\aa_bom;
use App\Models\Arbeitsanw\ERP\Artikel_Stamm;
use Illuminate\Support\Facades\DB;
public function loadstep($id)
{
$aa_doc_steps = aa_doc_steps::find($id);
//Stkl laden
$aa_doc_step_id=$id;
$aa_stkl_artikels = aa_bom::where('_x_zu_aa_doc_steps', '=', $aa_doc_step_id)
->leftJoin('sql_erp.ARTIKEL_STAMM', 'bom.art_nr', '=', 'Artikel_Stamm.ARTNR')
->orderBy('pos', 'asc')
->take(99)
->get();
return view('aa_edit_arbeitsschritt', compact('aa_doc_steps', 'aa_stkl_artikels'));
}
my model
<?php
namespace App\Models\Arbeitsanw\ERP;
use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;
use App\Http\Controllers\aa_stkl_form_controller;
class Artikel_Stamm extends Model
{
use HasFactory;
protected $connection = 'sql_erp';
protected $table = 'ARTIKEL_STAMM';
}

Answer 1

You can use the Laravel Eloquent Left join structure as an example
$ c = Customer :: leftJoin ('orders', function ($ join) (
$ join-> on ('customers.id', '=', 'orders.customer_id');
})
-> whereNull ('orders.customer_id')
-> first ();
You can look at this code structure. Also, you need to define $ fillable = ['table_column', 'table_column'] in the Model file.