we have recently upgraded Anlalytics postgresql db from 10x to 13x . We did not do in place upgrade but we did install new 13x version and copied the data from 10x to 13 x database/tables. When we changed the details under Enterprise Manager Repository connection to 13x version, we had to Initialize Analytics Repository which deleted all the previously copied data. And there is no way to skip this step . We want to have the feature where we can change the connection details like passworda etc., and still be able to retain old data when we Initialize the repository connections. We were asked to create a feature request as it is a known issue by R & D.
