将数据库编码修复为UTF8

I need to change encoding of whole database to UTF8.

I was connect to database like this before:

// MySQL connect information.
$username = "root";
$password = "";
$host = "localhost";
$database = "yac";

// Connect.
$connection = mysql_connect($host, $username, $password)
or die ("It seems this site's database isn't responding.");

mysql_select_db($database)
or 

die ("It seems this site's database isn't responding.");

my database content was stored to database without mysql_query("SET NAMES UTF8"); and data was like this:

باشگاه هوانوردان جوان

now recently I connect to database like this:

$mysql_username = "root";
$mysql_password = "";
$mysql_host = "localhost";
$mysql_database = "tick5";
$connection = mysql_connect($mysql_host, $mysql_username, $mysql_password) or die ("It seems this site's database isn't responding.");
mysql_select_db($mysql_database) or die ("It seems this site's database isn't responding.");
mysql_query("SET NAMES utf8"); 
mysql_query("SET CHARACTER_SET utf8");

and stored data is like this:

عنوان مقاله

since I use mysql_query("SET NAMES UTF8"); before INSERT queries I haven't any problem but now I need my old content and I want to change encoding and fix this.

How to do this?

NOTE : my tables Collation is utf8_unicode_ci

Try to see if this can help you. http://www.gentoo-wiki.info/TIP_Convert_latin1_to_UTF-8_in_MySQL

If you do not have a running Linux system, you can download an Ubuntu LiveCD and run it directly from the CD. http://www.ubuntu.com/download/desktop