When upgrading, the task fails with a message like:
This is due to the Hibernate bug https://hibernate.atlassian.net/browse/HHH-2208, which is fixed, but Confluence still uses an old version including this bug. Ordinarily, the workaround of creating a schema-local "all_objects" view has prevented issues which have come up, however in this case, that workaround does not work.
- Install Confluence into multiple schemas in the same Oracle database at a version below 5.2
- Attempt to upgrade one of them to 5.2
Follow the steps in the KB article Upgrade Failed with "Table '<Table Name>' has more than one primary key" Error Message