Our PostgreSQL database schema utilizes PostgreSQL's "Large Objects" and references them by the content column of the pgblobstore table. Since this was only an integer column, PostgreSQL's vacuumlo tool deemed the Large Objects orphaned and deleted them. Now, we have changed the column type to oid to save our Large Objects from vacuumlo.

Note, that it is not possible to start a Content Server of a previous release on the database after the new Content Server has adapted the database tables. You should always make a backup of the Content Server database before upgrading. Due to our overall database versioning schema, this applies to Content Servers with any database, even though the actual change affects only PostgreSQL!

(CMS-21879)