how to use raw sql query in laravel 8 controller code example

Example 1: laravel sql query

use Illuminate\Support\Facades\DB;

$users = DB::select('select * from users');

foreach ($users as $user) {
    echo $user->name;
}

Example 2: TRANSACTON LARAVEL QUERY BUILDER

DB::beginTransaction();

try {
    DB::insert(...);    
    DB::commit();
} catch (\Throwable $e) {
    DB::rollback();
    throw $e;
}