mysql中php生成唯一ID

<?php

//uniqid官方手册function create_guid($namespace = '') {static $guid = '';$uid = uniqid("", true);$data = $namespace;$data .= $_SERVER['REQUEST_TIME'];$data .= $_SERVER['HTTP_USER_AGENT'];$data .= $_SERVER['REMOTE_ADDR'];$data .= $_SERVER['REMOTE_PORT'];$hash = strtoupper(hash('ripemd128', $uid . $guid . md5($data)));$guid = '{' . substr($hash, 0, 8) . '-' .substr($hash, 8, 4) .'-' .substr($hash, 12, 4) .'-' .substr($hash, 16, 4) .'-' .substr($hash, 20, 12) .'}';return $guid;}?>