Getting mysql_set_charset() error

I am seeing the following error on multiple pages of my admin including the add new post admin, the add new page admin, the plugins tab, and the permalinks settings page and other random admin pages at other times.

Warning: mysql_set_charset() expects parameter 2 to be resource, boolean given in /home/impactib/public_html/wp-includes/wp-db.php on line 541

I even attempted a fresh install of WordPress before installing any plugins, and tried to add multi-db first. Still came up with the same message.

Any help. This is really frustrating.