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Using PDB Relocation to Upgrade an Individual PDB (Doc ID 2771716.1)

Last updated on APRIL 27, 2021

Applies to:

Oracle Database - Enterprise Edition - Version 12.2.0.1 and later
Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Gen 2 Exadata Cloud at Customer - Version All Versions and later
Information in this document applies to any platform.

Goal

 

With the release of Oracle Multitenant, one of the main benefits is the portability of each individual Pluggable Database (PDB).  It is possible to move the self-contained contents of a single PDB from one Container Database (CDB) to another.  In the initial release of Oracle RDBMS 12cR1 this required the PDB to be unplugged from the source CDB and plugged into the destination CDB which could have the potential for extensive downtime.  With 12cR2 the concept of PDB Relocation was introduced, allowing movement of a PDB from one container to another through two SQL commands where the physical copy of the files is performed while the source PDB remains accessible to users and applications.  The final phase of relocation introduces a short downtime of less than 10 minutes to complete the operation The final phase of relocation introduces a short downtime of less than 10 minutes to complete the operation and the upgrade time will vary, generally 30 to 45 minutes based on installed database options and PL/SQL objects, synonyms and used datatypes with complete application downtime typically less than 1 hour. 

The primary use cases for PDB Relocation are from a planned maintenance perspective:

Each of these operations is a physical move of the PDB from one container to another.  There is no reorganization of the PDB or its data as part of this move.

While the low downtime relocate functionality is more directed towards moving PDBs between CDBs of matching patch and version levels, it is also possible to relocate a PDB from a lower to higher version CDB.  Additional downtime is required to perform the upgrade at the destination CDB, but this allows you to upgrade individual PDBs in isolation rather than having to upgrade all PDBs in the CDB at one time.

One of the advantages of Oracle Multitenant is the ability to Manage Many as One and upgrade all PDBs and the CDB together at the same time, saving time and effort.  This document will focus on the exception case where a single PDB is ready to upgrade but other PDBs in the container database are not.

NOTE: During the relocation and upgrade process your applications will experience downtime.  For typical environments you can expect one hour or less, however the downtime is dependent on optional database products installed in the PDB in addition to application PL/SQL code.  It is highly recommended you test this process in a test/dev environment with a representative copy of the PDB to determine what your approximate downtime will be.

This paper will document the process for relocating a pluggable database and upgrading it at the destination, describing:

For PDB Relocation where upgrade of the PDB is not required, please see Using PDB Relocation to Move a Single PDB to Another CDB Without Upgrade <Document 2771737.1>.

Solution

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In this Document
Goal
Solution
 Prerequisites
 Performing a Pluggable Database (PDB) Relocate with Upgrade
 Steps to Prepare for the Relocate
 Steps to prepare for Upgrade
 Steps to Perform Phase 1 of the Relocate – Source PDB Remains Available
 Steps to Perform Phase 2 of the Relocate – Application Downtime Begins
 Steps to Perform after the Relocate has Completed
 Steps to Perform the Upgrade and Restart Application Services
 Steps to Perform after the Upgrade Completes
References

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