Obtaining the following error when attempting to edit pages in WordPress:

Fatal error: Call to undefined method wpdb::get_blog_prefix() in /wordpress-admin/includes/user.php online 260

The road on 260 of this file states:

if ( !is_multisite() )
        $level_key = $wpdb->get_blog_prefix() . 'user_level';
    else
        $level_key = $wpdb->get_blog_prefix() . 'capabilities'; // wpmu site admins don't have user_levels

No new plug ins happen to be installed with no admin files happen to be edited.