<?php
/* vars for export */
// database record to be exported
$db_record = 'XXX_TABLE_NAME_XXX';

// optional where query
// filename for export
$csv_filename = 'db_export_'.$db_record.'_'.date('Y-m-d').'.csv';
$hostname = "XXX_HOSTNAME_XXX";
$user = "XXX_USER_XXX";
$password = "XXX_PASS_XXX";
$database = "XXX_DATABASE_XXX";
$port = 3306;
$conn = mysqli_connect($hostname, $user, $password, $database, $port);

if (mysqli_connect_errno()) {
  die("Failed to connect to MySQL: " . mysqli_connect_error());
}

// create empty variable to be filled with export data
$csv_export = '';
// query to get data from database
$query = mysqli_query($conn, "SELECT * FROM ".$db_record.");
$field = mysqli_field_count($conn);
// create line with field names
for($i = 0; $i < $field; $i++) {
  $csv_export.= mysqli_fetch_field_direct($query, $i)->name.';';
}
// newline (seems to work both on Linux & Windows servers)
$csv_export.= PHP_EOL;
// loop through database query and fill export variable
$newRows = [];
while($row = mysqli_fetch_array($query)) {
  $id = $row['id'];
  $names = explode(", ", $row['name']);
  foreach($names as $name){
    $newRows[] = [$id, $name];
  }
}

// create line with field values
for($i = 0; $i < $field; $i++) {
  $row = $newRows[$i];
  $csv_export.= '"' . $row[0] . ',' . $row[1] . '";';
}

$csv_export.= PHP_EOL;

// Export the data and prompt a csv file for download
header("Content-type: text/x-csv");
header("Content-Disposition: attachment; filename=".$csv_filename."");
echo($csv_export);