Yesterday I attended DOAG conference in Mannheim about migrating Oracle databases.

First presentation was about challenges about migrating to multitenant databases. With Oracle 20 it is probably not possible anymore to create a non CDB database or to upgrade from a non CDB database. So in the next years all databases have to be migrated to multitenant architecture. Problems with licensing, different charactersets were covered and some migration methods to PDB were shown.
In the second lecture causes of failures of database migrations were shown which were not caused by database technology itself but by surrounding technologies and human errors.
In the third speech a new migration method with RMAN incremental backups in combination with transportable tablespaces was shown, this is very interesting for migration of big databases.
Also a migration method with duplicate command with noopen option was presented.

Last but not least an entertaining show about migration projects was hold, the lessons learned were presented in Haiku (Japanese poem form).