Depending on the number of computers you are auditing, the level of detail you capture, and the length of time captured activity must be available for review, an audit store database can grow too large to manage effectively in a short period of time.
To prevent the audit store database from growing too large, you can split it into multiple databases. Only one database at a time can be the active—that is, the database currently receiving captured activity from an audited computer and its collector service.
However, because large databases are harder to manage and take longer to search than smaller ones and you cannot allow a single active database to grow indefinitely, you can change the active database to be an attached database—that is, available for searching and retrieving stored information but no longer receiving captured activity—and make a new database the currently active database.
Changing which database is active without interrupting the monitoring of audited computers is also referred to as rolling or rotating the database. By adding new databases and changing the audit store’s active database to an attached database before it gets too large, you can optimize database performance and storage requirements.