Overview of Converting Databases During Upgrades

There are two methods to convert non-CDBs to multitenant architecture Oracle Databases during upgrades, and several different technologies you can use.

Starting with Oracle Database 21c, non-CDB Oracle Database upgrades to non-CDB architecture are desupported. Review the upgrade options for this release.

Options for Manual Migration and Upgrades of Oracle Database Non-CDB Architecture to the Multitenant Architecture

There are two ways you can perform manual migrations and upgrades of non-CDBs to Oracle Database container databases (CDBs) and pluggable databases (PDBs), which use the multitenant architecture:

  • Convert the non-CDB to a PDB before upgrade.

    With this option, you plug in the non-CDB Oracle Database release to the same release CDB. (For example, plug in a non-CDB Oracle Database Release 19c into an Oracle Database 19c release CDB). Finish converting the non-CDB Oracle Database to a PDB. Then, upgrade the entire CDB, with its PDBs, to Oracle Database 21c.

  • Plug in the non-CDB, upgrade, and finish converting the non-CDB to a PDB after upgrade.

    With this option, you plug in a non-CDB Oracle Database release to an Oracle Database 21c CDB. Upgrade the plugged-in non-CDB Oracle Database to Oracle Database 21c. Then, finish converting the non-CDB Oracle Database to a PDB.

Upgrade Technology Methods for Options

The following table lists methods that you can use to convert upgrades, including references to availability issues. It also provides references to the documentation that describes how to carry out each upgrade method.

Table 1-3 Technology Methods for Migrating and Upgrading Databases During Upgrades

Method Description Reference
AutoUpgrade for Oracle Database Use the AutoUpgrade tool to automate the upgrade of your database. Refer to the topic "Using AutoUpgrade for Oracle Database Upgrades"

Oracle Data Guard Transient Logical Standby database

Use an existing physical standby database to perform a database upgrade by temporarily converting it to a logical standby database, and then converting it back to a physical standby.

Refer to the topic “About Upgrading Using Standby Databases”

Parallel Upgrade Utility Use the Parallel Upgrade Utility to perform a manual upgrade of Oracle Database. If the Oracle Database is a non-CDB, then you must convert the database to a PDB Refer to the topics under "Upgrading Oracle Database with DBUA or Parallel Upgrade Utility"
Oracle GoldenGate synchronization of production and standby databases for zero downtime upgrades Use Oracle GoldenGate with software upgrades and with Oracle Database data migration procedures to carry out a synchronization approach to maintaining availability during an upgrade. Starting with Oracle Database 21c, you can use the Zero Downtime Upgrade feature of Fleet Patching and Provisioning to convert non-container Oracle Database instances (CDBs) to multitenant architecture Oracle Database instances. When you use this feature with Oracle GoldenGate, you can initiate the entire upgrade and conversion as a single operation.
  • Use RMAN restore and upgrade to set up a standby database running the earlier release software using an existing backup

  • Upgrade the standby database to the new Oracle Database release

  • Move the entire database and synchronize the standby database with the production database using the following tools:

    • Oracle Data Pump

    • Transportable Tablespaces (TTS)

    • CREATE TABLE AS SELECT (CTIS) to create new tables and populate them with rows from specified queries.

    • INSERT AS SELECT (IAS) to create nonpartitioned tables

  • Use Data Load/Unload to load data into the new database release, and unload data from the old database release

Refer to Oracle GoldenGate documentation, and relevant Oracle Database documentation for your use case.

Oracle Enterprise Manager Cloud Control

Oracle provides Cloud Control support for performing database upgrades with Oracle Database 12c and later releases. This option requires that you purchase the Enterprise Manager Lifecycle Management Pack.

Refer to Online help in Oracle Enterprise Manager Cloud Control


Upgrades of Oracle Grid Infrastructure (Oracle Clusterware and Oracle Automatic Storage Management) are carried out separately, before Oracle Database upgrades. You must complete Oracle Grid Infrastructure upgrades before you upgrade Oracle Database installations. Other features installed with Oracle Database can have additional upgrade requirements.