Database Error of CI on my online server HELP!!!!!

[eluser]Xeroxeen[/eluser]
[quote author="noideawhattotypehere" date="1377857228"]check your /etc/mysql/my.cnf, see bind-address, maybe somehow it got changed to listen to some other ip?

run this and see if that works, so we know its 100% codeigniters fault:

Code:

<?php
$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
if (!$link) {
    die('Could not connect: ' . mysql_error());
}
echo 'Connected successfully';
mysql_close($link);
?>

[/quote]

Hi run this code.It's showing 'Connected successfully'.So that means there isn't issue in server?What can i do now?