Laravel trim in query

guys, i have a column name called attachment_files in my query and save it in DB this way 1641210480.Python-Cheat-Sheet.pdf. i need when i make the query to return it this way Python-Cheat-Sheet.pdf how can i do it?

 $getMerchant = Merchant::leftjoin('ratings', 'ratings.merchant_id', '=', 'merchants.id', 'merchant_qualification', 'merchant_qualification.qualification')

                ->select('merchants.*', DB::raw('round(avg(ratings.rate),1) as rate'))
                ->when($request->qualification_id > 0, function ($builder) use ($request) {
                    $builder->whereHas('merchant_qualification.qualification', function ($builder) use ($request) {
                        $builder->where('id', $request->qualification_id);
                    });
                })
                ->when(($request->date != null && $request->date != 0) || ($request->time != null && $request->time != 0), function ($b) use ($request) {
                    $b->whereHas('merchantAvailability', function ($b) use ($request) {
                        if (($request->date != null && $request->date != 0)) {
                            $b->where('date', $request->date);
                        }
                        if ($request->time != null && $request->time != 0) {
                            $b->where('from_time', '<=', $request->time)
                                ->where('to_time', '>', $request->time);
                        }
                    });
                })
                ->where($cond)
                ->where('is_approved', '=', '1')
                ->orderby($orderColumns, $orderDirection)
                ->groupBy('id')
                ->when($request->rate > 0, function ($builder) use ($request) {
                    return $builder->having(DB::raw('round(avg(ratings.rate),1)'), '>', $request->rate - 1)
                        ->having(DB::raw('round(avg(ratings.rate),1)'), '<=', $request->rate);
                })
                ->with($det)
                ->limit($request->limit)
                ->get();


            return $getMerchant;
        } catch (\Exception  $e) {
            return $this->returnMessage($e->getMessage());
        }
    }

    public function getMerchants(Request $request)
    {
        $request->request->add(['showDetails' => '0']);

        $getMerchant = $this->getMerchantData($request);
        
        $getMerchant = $getMerchant->map(function ($getMerchant) {
            return (object)$getMerchant;
        });

        return $this->showAll($getMerchant);
    }