Query to set all users "Display Usergroup" to Default?

[tfw2005]

Bump, in case this got lost in the holiday shuffle.

Example of what I am looking to do is:

UPDATE user SET reputation = 0

That would be used for resetting reputation.

I am looking to reset the display group for members with multiple usergroups. So something like:

UPDATE user SET displaygroup = 'default'

Not sure if that is right, so if anyone could sound off on what the query to do that is, much appreciated.

Thanks!