The multitenant architecture introduced in Oracle Database 12c enables an Oracle database to function as a multitenant container database (CDB) that includes zero, one, or many customer-created pluggable databases (PDBs). A PDB is a portable collection of schemas, schema objects, and nonschema objects that appears to an Oracle Net client as a non-CDB. All Oracle databases before Oracle Database 12c were non-CDBs.
With the introduction of CDBs and PDBs in Oracle Database 12c, more upgrade scenarios are available than in previous versions of Oracle Database.
This chapter includes information about these upgrade scenarios:
Upgrading a pre-Oracle Database 12c Release 1 (12.1.0.2) non-CDB to an Oracle Database 12c Release 1 (12.1.0.2) non-CDB
See "Upgrading a Database Using DBUA" for the steps to follow for this upgrade scenario.
Upgrading a pre-Oracle Database 12c Release 1 (12.1.0.2) PDB to an Oracle Database 12c Release 1 (12.1.0.2) PDB
See "Upgrading a PDB" for more information about this upgrade scenario.
See Also:
Oracle Database Concepts for an overview of the multitenant architecture
Oracle Database Administrator's Guide for complete information about creating and configuring a CDB
Oracle Database Upgrade Guide for information about other Oracle Database upgrade scenarios