PDO in Codeigniter

[eluser]Ickes[/eluser]
[quote author="kgill" date="1246587626"]
$DB =& new PDO($params['dbdriver'].':host='.$params['hostname'].';dbname='.$params['database'], $params['username'], $params['password']);
[/quote]

OK, can I have a little more help?

The arguments to create a new PDO instance are:
new PDO ($dsn, $username, $password, $options)

So as given in the kgill code...
$username = $params['username']
$password = $params['password']

Now I believe the ; should actually be : which gives us
$dsn = $params['dbdriver'].':host='.$params['hostname'].'<b>:</b>dbname='$params['database']

But this isn't working for me. I see:
* $dsn = 'driver://username:password@hostname/database';

so should it be reconfigured to
$params['dbdriver'].'://'.$params['username'].':'.$params['password'].'@'.$params['hostname'].'/'.$params['database']

?

This works but sure seems lengthy and not necessarily correct.

Does anyone have any feedback? Thanks.