iMatteh

ejakabo, greetz from russian ipboard community, we have exactly what you need =)

1) For average sized forums - database conversion script based on PHP:

<?php
// Database info

include("conf_global.php");

$dbhost = $INFO['sql_host'];
$dbuser = $INFO['sql_user'];
$dbpass = $INFO['sql_pass'];
$dbname = $INFO['sql_database'];

//---------------

header('Content-type: text/plain');

$dbconn = mysql_connect($dbhost, $dbuser, $dbpass) or die( mysql_error() );
$db = mysql_select_db($dbname) or die( mysql_error() );

$sql = "ALTER DATABASE `".$dbname."` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci";
$result = mysql_query($sql) or die( mysql_error() );
print "Database changed to UTF-8.\n";

$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 $table DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci, CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci";
mysql_query($sql) or die( mysql_error() );
print "$table changed to UTF-8.\n";
}

mysql_close($dbconn);
?>

Upload this script as "any_name_you_like.php" in forum's root folder and execute. Be careful with large databases - be sure to correctly configure max_execution_time limit.

2) For large forums - 2 step conversion:

Step 1:

<?php
// Database info
 
include("conf_global.php");
 
$dbhost = $INFO['sql_host'];
$dbuser = $INFO['sql_user'];
$dbpass = $INFO['sql_pass'];
$dbname = $INFO['sql_database'];
 
//---------------
 
header('Content-type: text/plain');
 
$dbconn = mysql_connect($dbhost, $dbuser, $dbpass) or die( mysql_error() );
$db = mysql_select_db($dbname) or die( mysql_error() );
 
$sql = "ALTER DATABASE `".$dbname."` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci;\n";
 
$exec_sql = 'SHOW TABLES';
$result = mysql_query($exec_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 COLLATE utf8_general_ci;\n";
}
mysql_close($dbconn);
 
echo $sql;

As in first method, upload this script into forum's root folder and execute. Follow it's URL and you'll get a mysql dump file. Save it,  for example, as win2utf.sql and upload to /somewhere/at/server

Step 2:
Connect to your sever throught SSH and run:

#mysql -uusername -p dbname < /somewhere/at/server/win2utf.sql

Thats it. More info and russian support topics: 1, 2.

Always make a backup before performing any operations with database!