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“.… [Read More]

noncdb_to_pdb.sql – why does it take so long?

What is noncdb_to_pdb.sql?

noncdb_to_pdb.sql - Why does it take so long?The script noncdb_to_pdb.sql gets run only once in the life span of your database. It gets executed when a regular Oracle database (non-CDB) gets move to become part of a Single-/Multitenant deployment as a pluggable database (PDB). But why does it take so long?

You will never run this script again for this database.… [Read More]

Issue with 2k and 4k db_block_size – ORA-1450 when upgrading to Oracle

Recently we got alerted by a customer and a colleague from Italy about an issue with the upgrade from Oracle 12.1.0.x to Oracle if – and only if – your database got created with 2k or 4k db block size.


If your database got created with 2k or 4k db block size, and you attempt an upgrade from any upgrade-supported Oracle version to Oracle Database the upgrade – regardless of DBUA or catctl.pl – will fail with an ORA-1450: maximum key length (1478) exceeded.… [Read More]

Upgrade Everything at Once – Multitenant Upgrade from Oracle 12.1 to 12.2

I did blog about this topic a while back.

Upgrade PDBs – Everything At Once (Full CDB Upgrade)

Theory is nice but it’s a big difference when you do it the first time with a non-lab deployment at a customer with a real Multitenant database with almost 100 PDBs.Then you learn that neither the documentation nor my previous blog post contain all the necessary steps.… [Read More]

Multiple hop upgrades? Execute the matching preupgrade scripts for each hop

We discussed an interesting upgrade case last week together with our upgrade colleagues in Support – and learned the double-hop (or triple-hop) upgrade case is not described in the documentation somewhere.

What is a multiple-hop upgrade?

Triple Jump

Triple Jump – Willie Banks – Olympics 1988 Seoul

Actually this describes the case where somebody can’t upgrade directly and has to do several upgrades in a sequence to reach the targeted release.… [Read More]

Upgrade to Oracle Database 12.2 and Converting it into an 12.2 PDB (plugin)

2 customers requested a bit more explanation on how to:
Convert and Plugin an Oracle 12.1 non-CDB database into an Oracle 12.2 container database

Cool, I like that 🙂 I will do this right away and use the approach to Upgrade first, then Plugin afterwards.

Upgrading an Oracle database to Oracle

First the preupgrade.jar must be executed – please download always the most recent version from MOS Note:884522.1 as the version we publish is usually newer including important improvements (and fixes) than the version you’ll get with the release drop.… [Read More]

Upgrade to Oracle Database 12.2 – New MOS Notes

Some very helpful MOS Notes got published regarding the upgrade to Oracle Database

Furthermore check regularly for Known Issues and Alerts – currently the note has no content but exists already:

–Mike… [Read More]