You might need to upgrade PeopleSoft history, or archive, data when you upgrade PeopleSoft from version 8.9 to 9.1. Upgrade history data so that you can view it in the upgraded version of the application.
For example, your organization archives data from PeopleSoft. The organization upgrades PeopleSoft from version 8.9 to version 9.1. The data in the history database is compatible with version 8.9. You must be able to view the data in version 9.1.
Contact Informatica Global Customer Service three months before you plan to upgrade to a newer version of PeopleSoft. Informatica Global Customer Service will send you the history upgrade scripts required for the version you are upgrading to.