<?php

function error($message) {
  echo($message."\n");
  exit;
}

function mysql_open() {
  $username = '...';
  $password = '...';
  $database = '...';
  $mysqli = new mysqli('localhost',$username,$password,$database);
  if(mysqli_connect_error()) error("can't connect to database");
  return $mysqli;
}

$i = 50;

$mysqli = mysql_open();

$res = $mysqli->query("select * from messages where id > $i");
if(!$res) error("query error");

while($row = $res->fetch_object()) {
  echo $row->id."\n";
}

$mysqli->close();

?>