The latest version of the Oracle Database, introduced in 2013 ("c" stands for "cloud"). Oracle 12c added numerous enhancements for queries, migration, replication and recovery. Containers and Pluggable Databases were introduced, a major new structure that targets multitenancy (multiple customers sharing server resources). Memory and process are controlled by the Container Database, and the Pluggable Databases (PDBs) store the user data. For maintenance, only the Container needs to be upgraded, patched and monitored. See
Oracle Database.