Beispiel Code für das Youtube Video https://youtu.be/vE7AXqs2dKk

export.php

<?php

error_reporting(-1);
ini_set('display_errors', 'On');

$array = [
  ['Row 1','Row 2','Row 3'],
  ['Col 1','Col 2','Col 3'],
  ['Col 1','Col 2','Col 3'],
];



$file = new SplTempFileObject();

foreach($array as $row){
    $file->fputcsv($row);
}

$file->rewind();

header("Content-Type: text/csv");
header('Content-Disposition: attachment; filename="temp.csv"');
$file->fpassthru();