https://support.ca.com/us/knowledge-base-articles.TEC1430711.html - Can I use the APM Config Import Tool to migrate from Oracle to Postgres?
A customer is upgrading his EM from a lower version of APM to the latest version. In the lower version, he is using Oracle database. Now in the latest version, he wants to use the Postgres database instead of Oracle. So, he exports data from Oracle using configexport command. This will generate export_cem_oracle.xml file. Using this file, he will now try to import the data into Postgres database using configimport command.
This tool is provided AS-IS without official support. It is highly recommended to backup the Oracle and Postgres systems before deploying the Export Oracle utility