mySQL vs mySQLi on Drupal

apps

#1

In Drupal4.7.5/sites/default/settings.php, should I set line 87 to mysql or mysqli?

i.e.

$db_url = 'mysql://user:pass@mysql.sameertahir.com/drupaldb';or

On Dreamhost, what are the benefits of using one rather than the other?

thanks for any info!