If your mysql connection ever goes down for more than 10 minutes please send in a support message. And even if an entire mysql server crashed and had to be rebooted it would not take more than an hour.
If any service has been down for you for an entire day, it is very, very unlikely that the problem is server wide or system wide. If something like this was occurring, it would definitely be posted on DreamHostStatus.com.
The one exception to the rule is if the problem is intermittent. In that case the monitoring tools may be missing the problem. So in that case you should send in a support request.