Laravel select for update && start transaction && Fetch commands

lockForUpdate()   

$model = \App\Models\User::lockForUpdate()->find(1);

https://stackoverflow.com/questions/34556511/laravel-lockforupdate-pessimistic-locking

Transaction

https://laracasts.com/discuss/channels/general-discussion/how-properly-use-the-lockforupdate-method

use Illuminate\Support\Facades\DB;

https://stackoverflow.com/questions/49814785/how-can-i-use-transaction-with-eloquent-laravel-5-5

       DB::beginTransaction();
        try {
            $project = Project::find($id);
            $project->users()->detach();
            $project->delete();
            DB::commit();
        } catch (\Exception $ex) {
            DB::rollback();
            return response()->json(['error' => $ex->getMessage()], 500);
        }


https://stackoverflow.com/questions/16846531/how-to-read-fetchpdofetch-assoc
PDOStatement::fetch returns a row from the result set. The parameter PDO::FETCH_ASSOC tells PDO to return the result as an associative array.