What is the impact of the ZCM database failing or being taken off line?

Scenario - ZCM satellites and primaries are ok but the database server is down?

I understand that ZCC admin of ZCM would not be possible at this time but I'm more concerned about the what the impact would be on existing working clients and bundle assignments both short term and longer term (i.e. after refreshes, cache expiry etc).

Has anyone had any experience of this scenario?