To enable the purging function for the reporting database, which is separate from the process instance purging outlined in the documentation, follow these instructions.
Log in to CA Process Automation as a member of the pamadmin group.
Select the Configuration tab
Click on Domain, right click and lock.
Select the Properties tab
For 'Option to Purge Reporting Data' change that from Do Not Purge Reporting Data to Purge Reporting Data Daily
For 'Start Time to Purge Reporting Data Daily' you can leave this as the default of 00:01 - this means it will start at 1 minute after midnight.
For 'Number of Days to Keep Reporting Data' the default value is 10 days. This is going to depend on what type of reports you need to run and how long the data needs to be kept. This number is going to be the key to keeping the database manageable.
If you set the number too high, like 60 or 90 (again, all dependent on how heavily Process Automation is used) the reporting database can grow quite large and cause a performance hit in Process Automation.
Click on the Save icon in the upper right when you have completed your updates and then unlock the domain.