Is it possible to get node information in a mysql-database?

So in case it wasn't clear, you can get the data in two different ways:

1. from REST API: for batched or semi-realtime data gathering
2. from MQTT stream: for realtime pub/sub data gathering

After that it's up to the developer what to do with it (saving in mysql db, real-time display using some framework like Meteor, printing it on a dot matrix printer, etc). Also because, as @pz1 says, the data can be in any format, there aren't out-of-the-box visualisations available; even though I think we - as a community - could supply some example graphing for common data formats like json, to get going.