数据库中config.php的管理员密码

我是新的php我有一个问题。我有一个网站的管理员密码是在config.php中定义的，请参见下面的

?>
<?
// admin constants
define("ADMIN_LOGIN","admin");      // username of administrator to login
define("ADMIN_PASSWORD","123456");      // password of administrator to login
// admin e-mail
define("ADMIN_NAME","Admin");       // username of administrator to login
define("SITE_NAME","XXX");
define("SUPPORT_EMAIL","xxx@yahoo.com");
define("MAIL_TO_CUSTOMER_NAME","DoNotreply@xxx.com");
define("MAIL_TO_CUSTOMER","DoNotreply@xxx.com");    // email of website admin
define("ADMIN_EMAIL","info@xxxs.com");  // email of website admin
define("DOMAIN","");

我想从数据库中获得管理员密码，所以我应该有选项通过前端更改密码。