I have upgraded from Plesk 7.5.6 to Plesk 8.1 (windows)
Everything seems to work fine but when I click on the Database icon in the main plesk page I get the following error:

DB query failed: Unknown column 'db_server_id' in 'field list'
---------------------- Debug Info -------------------------------
0: C:\Program Files\SWsoft\Plesk\admin\plib\common_func.php3:211
db_query(string 'select db_server_id, count(id) as `count` from data_bases group by db_server_id')
1: C:\Program Files\SWsoft\Plesk\admin\plib\DatabaseServerList.php:59
DatabaseServerList->fetchDatabaseServerList()
2: C:\Program Files\SWsoft\Plesk\admin\plib\class.cList.php3:94
cList->fetchList()
3: C:\Program Files\SWsoft\Plesk\admin\plib\class.cList.php3:113
cList->init()
4: C:\Program Files\SWsoft\Plesk\admin\plib\DatabaseServersForm.php:25
DatabaseServersForm->assign(string '', boolean false)
5: C:\Program Files\SWsoft\Plesk\admin\htdocs\server\db_servers.php:128

Looked into the PSA database, 'db_server_id' column doesn't exist at all?
Meanwhile new tables for Plesk 8 are available in the PSA that means Plesk 8 has somehow updated the PSA database...

Really appreciate your help,