export csv using fputcsv in PHP

export-csv.php

<?php
function export(){

  $filename = 'users_'.date('Ymd').'.csv';
  header("Content-Disposition: attachment; filename=\"$filename\"");
  header("Content-Type: application/vnd.ms-excel");

  /* Connect to a MySQL database using driver invocation */
  $dsn = 'mysql:dbname=test_db;host=127.0.0.1';
  $user = 'test';
  $password = 'test';

  try {
    $dbh = new PDO($dsn, $user, $password);
  } catch (PDOException $e) {
    echo 'Connection failed: ' . $e->getMessage();
  }

  $sql = "SELECT * FROM TABLE_NAME";

  $sth = $dbh->prepare($sql);
  $sth->execute();
  $result = $sth->fetchAll(PDO::FETCH_ASSOC);

  // file creation
  $file = fopen('php://output', 'w');

  $header = array("Category Name","Product Name","Price","Detail","Description");

  fputcsv($file, $header);

  foreach ($result as $key=>$line){
    fputcsv($file,$line);
  }

  fclose($file);
  exit;
}

export();