Answers for "laravel join and condition eloquent model"

join in laravel eloquent

$customer = DB::table('customers')
                ->join('shops', 'customers.shop_id', '=', 'shops.shop_id')
                ->where('customer_contact', $contact_no)
                ->get();

laravel eloquent join two models

Event::whereHas('participants', function ($query) {
    return $query->where('IDUser', '=', 1);
})->get();