php study

http://www.phpro.org/tutorials/Introduction-to-PHP-PDO.html#7.2

http://henryranch.net/software/ease-into-sqlite-3-with-php-and-pdo/

http://cn2.php.net/manual/en/book.hash.php

http://www.enet.com.cn/article/2005/0217/A20050217390810.shtml

http://email.about.com/od/emailprogrammingtips/qt/PHP_Email_SMTP_Authentication.htm

http://pear.php.net/manual/tr/package.mail.mail.intro.php