Can you select a PDB’s character set?

Can you select a PDB's character set?Since Oracle Database a Multitenant container database can host PDBs with different character sets. This was a huge restriction in Oracle Database 12.1., at least outside the US and Canada. Here in Germany alone you may find plenty of different database character sets, for instance WE8ISO8859P1, WE8ISO8859P9, WE8ISO8859P15, WE8MSWIN1252, maybe still some old WE8DEC – and of course the unicode ones UTF8 and AL32UTF8.… [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]

Non-CDB architecture still exists in Oracle Database 12.2.

I received a question whether the Non-CDB architecture still exists in Oracle Database 12.2.from 3 different colleagues in the past week:

“Does Oracle Database 12.2 still allow us to create non-CDB databases?”

And as I get this question at every customer-facing workshop these days as well before being able to talk about Single/Multitenant – I think it is important to clarify it.… [Read More]

Install components in Multitenant ALWAYS with

I did blog several times about how to remove an unwanted component from a database. But yesterday I came across this interesting scenario worth a blog post.

How to install a component afterwards in Single-/Multitenant?

I haven’t checked all the MOS Notes but I recognized that some MOS Notes explaining how to (re-)create a component such as JVM are not updated to deal with a Single and/or Multitenant environment as they simply call the scripts from SQL*Plus.… [Read More]


In Oracle Database 12.2 (available in the Oracle DBaaS Cloud) there’s a new functionality called “PDB LOCKDOWN PROFILES“. Actually the parameter came already in undocumented and not functional in Oracle Database (see here).

PDB Lockdown Profiles

PDB Lockdown Profiles are meant as a granular way to restrict or enable access – mostly under the aspect of using the database in a highly shared environment but requiring security.… [Read More]

SPFILE Parameter: max_pdbs – a must for Single Tenant

Sometimes my job has a aspect making me smile at the end of the day 😉

I sat together with Johannes Ahrends during a talk at the OUGN Conference on the boat from Oslo towards Kiel. And we were discussing afterwards why there’s no official way to limit the number of PDBs which will be essential for customers wanting to go the Single Tenant track.… [Read More]

PDB unplug/plug/patch with PSUs or BPs

This question was posted on the blog a few days ago referring to my previous blog posts describing the two techniques to upgrade in an Oracle Multitenant environment:


We are planning to upgrade from to
The plan is to create new oracle home and
gradually moving PDB from to
[Read More]