Back up your database and APEX applications
Another important step that many users tend to overlook is the backup stage. As I said, the APEX installation/upgrade process is very simple and straightforward. However, it's still a major operation on your database and things might go wrong, and it doesn't have to be your fault.
You should back up your database prior to any installation or upgrading of APEX. In case of the latter, I strongly recommend that you also export all the APEX applications, so in case of problems in the upgrade, it won't be necessary to restore the entire database.
