https://www.linkedin.com/learning/oracle-database-19c-multitenant-architecture
Oracle introduced the multitenant architecture in version 12.1.0.2 as an available option, but starting with 19c, creating a multitenant database is the only option for a new database. In this course, Oracle database administrator Bob Bryla helps DBAs create and effectively utilize resources within multitenant databases.
Bob shows how to manage one or more multitenant databases on the same server, how to create the CDB, create a PDB from the seed database, and clone a PDB to the same or another container. The multitenant architecture also has several new options when backing up and recovering databases and individual tables with the existing RMAN utility, so Bob explains new RMAN scenarios and details when to back up just the CDB root, the entire CDB, or individual PDBs. He also covers how to create and manage a special type of PD called an application PDB, also known as an application container, and shows how to leverage the versioning capabilities included with application containers.