Problem:

1. It is hard to follow the detailed requirements only to understand the database requirements (link from Support Matrix to docs)
2. It should be specified in one place. Currently it is specified in multiple places in docs making it harder to update (bound to be errors going forward)
3. The baseline is missing. We need to introduce the external database  as an option in the installation requirements

https://docs.openshift.com/acs/4.6/upgrading/upgrade-operator.html#operator-upgrade-modify-central-custom-resource-external-db_upgrade-operator