They are pretty much self explanatory but here it goes:
$dbhost is where your database is at, in most cases localhost, so it would be $dbhost = "localhost";
$dbname is your database name
$dbuser is the username you use to connect to your database
$dbpasswd is the database password
Step 3: Now it is time to execute the sql file. This can be done through the SQL tab in the phpMyAdmin tool.
Step 4: Now open the pn-changeinfo folder. Inside you will find a pn71x.zip and a pn72x.zip files. Inside these files is the changeinfo.php file that makes profile unification possible. So depending on which version of Postnuke you are using, you should overwrite the corresponding file.
If you are using Postnuke .714 or .713, please upload the pn71x.zip to your root of PostNuke and unzip it, or you could just unzip it on your local harddrive and upload it to the corresponding directory.
The same action is needed if you use Postnuke .720 or .721, but use pn72x.zip.