Oracle Multitenant

Database Migration from non-CDB to PDB – Overview

Today I’ll start a blog post series of several “how to” articles about database migration from non-CDB to PDB – Overiew. You’ll find a quick introduction below. And of course, the links to all the other related blog posts.

Database Migration from non-CDB to PDB – Overview

When you plan to move from non-CDB, the Oracle term for regular database deployments, to a Pluggable Database (PDB), you will migrate your database. It will become a PDB and run as part of a Container Database (CDB). This is a well known concept for several years now called Oracle Multitenant. If you …

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Can you simply switch from SE2 to EE with Oracle Multitenant

Oracle MultitenantThis question is coming up from time to time – and currently not covered in the official Oracle documentation as far as I know: “Can you simply switch from SE2 to EE with Oracle Multitenant?”

Yes, you can!

First of all, the switch is possible and tested. But you’ll have to satisfy a few requirements:

  • Both database versions must be the same
  • Both databases must have the same character set (in Oracle Database 12.1)

That’s it. Simply unplug your Standard Edition 2 PDB and plug it into your Enterprise Edition CDB.

In addition you may have to run several component …

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Why does the upgrade of PDB$SEED always take longer?

Upgrading the PDB$SEED takes always longer than any other container.
What is the reason for an upgrade of the PDB$SEED taking so much longer in a real world environment?

How does an upgrade with Oracle Multitenant work?

Upgrading the PDB$SEED takes always longerI have written several blog posts in the past about the different techniques to upgrade an Oracle Multitenant environment:

  1. Upgrade Everything At Once
  2. Upgrade via Unplug/Plug/Upgrade

The interesting case happens in the “Everything At Once“. The PDB$SEED takes significantly longer to upgrade than any other container.

Upgrading the PDB$SEED takes always longer?

Quick recap: The PDB$SEED is the (I call it) blueprint

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