VirtualCenter stores tasks, event, and performance data in the VirtualCenter database. Over time, data collection results in growth of the database files and a mechanism is needed to shrink these files.
VirtualCenter 2.x does not have a feature to purge or shrink old records from the database. For more information on shrinking databases after running the scripts provided in this article, see:
How to Shrink a Database (http://msdn.microsoft.com/en-us/library/ms189035.aspx) & (http://msdn.microsoft.com/en-us/library/ms189080.aspx)