It's possible it grew that size due to how the Tracking logs are set. (10MB per log will create a row for each log gathered to each of these tables and over time it will build up to a very large in size)
https://support.quest.com/messagestats/kb/97310
Please check the size of the MessageStats .LDF file on the disk where the database is and see if its the transaction log file that is very large.
If the LDF is large, you can look at this article:
https://support.quest.com/kb/63465
As far as a database cleanup goes, there are deletion jobs you can use and this article will guide you through Database Management node:
https://support.quest.com/messagestats/kb/97607
- If you create a data aging task for statistical data, please note that this is the actual message count data you're working with or how many messages are sent and received for example.
- A data aging task for Audit data, is the data for any auditing that you may have done over the years, which can grow the database as well.
- You would then want to look into running a Shrink on the database after you have set your data aging jobs:
