UPDATE smf_messages SET subject= REPLACE(subject, 'Ä°', 'İ')WHERE subject LIKE '%Ä°%';
UPDATE smf_messages SET subject= REPLACE(subject, 'ı', 'ı')WHERE subject LIKE '%ı%';
UPDATE smf_messages SET subject= REPLACE(subject, 'Ö', 'Ö')WHERE subject LIKE '%Ö%';
UPDATE smf_messages SET subject= REPLACE(subject, 'ö', 'ö')WHERE subject LIKE '%ö%';
UPDATE smf_messages SET subject= REPLACE(subject, 'Ãœ', 'Ü')WHERE subject LIKE '%Ãœ%';
UPDATE smf_messages SET subject= REPLACE(subject, 'ü', 'ü')WHERE subject LIKE '%ü%';
UPDATE smf_messages SET subject= REPLACE(subject, 'Ç', 'Ç')WHERE subject LIKE '%Ç%';
UPDATE smf_messages SET subject= REPLACE(subject, 'ç', 'ç')WHERE subject LIKE '%ç%';
UPDATE smf_messages SET subject= REPLACE(subject, 'ÄŸ', 'ğ')WHERE subject LIKE '%ÄŸ%';
UPDATE smf_messages SET subject= REPLACE(subject, 'ÄŸ', 'Ğ')WHERE subject LIKE '%ÄŸ%';
UPDATE smf_messages SET subject= REPLACE(subject, 'ÅŸ', 'ş')WHERE subject LIKE '%ÅŸ%';
UPDATE smf_messages SET subject= REPLACE(subject, 'Å', 'Ş')WHERE subject LIKE '%Å%';

<?php
// Database info
 
$dbhost = "localhost";
$dbuser = "k.adi";
$dbpass = "şifre";
$dbname = "vt_adi";
 
//—————
 
header("Content-type: text/plain");
 
$dbconn = mysql_connect($dbhost, $dbuser, $dbpass) or die( mysql_error() );
$db = mysql_select_db($dbname) or die( mysql_error() );
 
$sql = "SHOW TABLES";
$result = mysql_query($sql) or die( mysql_error() );
 
while ( $row = mysql_fetch_row($result) )
{
$table = mysql_real_escape_string($row[0]);
$sql = "ALTER TABLE $table DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci, CONVERT TO CHARACTER SET utf8";
mysql_query($sql) or die( mysql_error() );
print "$table changed to UTF-8.\n";
}
 
mysql_close($dbconn);
?>