does any know what is being saved in this SolarWindsOrion.mdf My database is now more than 4G's
What version of SQL are you running? Are you running SQL on a separate server? This just sounds like the actual database that stores everything (all polling data).
Some customers have a lot of traps and that fills up their database more quickly. You could try decreasing the number of traps or traps retention period (in the Settings - Orion Polling Settings page).
