When you create Multitenant databases with DBCA there are some Things to Know. And in Oracle Database 188.8.131.52’s Database Creation Assistant (DBCA) there is a common pitfall in the “Options” screen. It was grayed out in the previous release but when you choose to create a “custom” database you can select the options/components now.… [Read More]
What a strange topic. And I thought I never will blog about this. But as I have received the same question for the third time today, I think there’s a bit clarification needed. Lost AWR snapshots reappear in Oracle 12.2 in Multitenant pluggable databases.
Lost AWR snapshots reappear again in Oracle 12.2 in Multitenant
In a non-CDB database you have your local AWR data stored in the SYSAUX tablespace.… [Read More]
Since Oracle Database 12.2 an important feature works now for pluggable databases as a Fallback Strategy: Flashback Pluggable Database in Oracle 12.2. This was missing in Oracle Database 12.1.
Actually I missed this feature a lot as I use “Flashback” almost everyday. And you could only rewind the entire deployment with a
FLASHBACK DATABASE command.… [Read More]
At the moment I work with one of our reference customers, Swiss Mobiliar Insurance, on their Multitenant upgrade to Oracle Database 184.108.40.206. And we encountered an “interesting” issue. After upgrade we received an ORA-44787 making it impossible to switch between containers with “
alter session set container=pdb1;” commands.… [Read More]
I have received several questions from customers in the past weeks using Oracle Multitenant about the parameter
exclude_seed_cdb_view.It magically disappeared and morphed into
_exclude_seed_cdb_view since Oracle Database 220.127.116.11. To be fair, the
exclude_seed_cdb_view is listed in the list of obsolete parameters in Oracle Database 18.104.22.168.
What is EXCLUDE_SEED_CDB_VIEW?
This parameter hides everything belonging to the
PDB$SEED from the usual queries.… [Read More]
This question is coming up from time to time – and currently not covered in the official Oracle documentation as far as I know: “Can you simply switch from SE2 to EE with Oracle Multitenant?”
Yes, you can!
First of all, the switch is possible and tested. But you’ll have to satisfy a few requirements:
- Both database versions must be the same
- Both databases must have the same character set (in Oracle Database 12.1)
That’s it.… [Read More]
Upgrading the PDB$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?
I have written several blog posts in the past about the different techniques to upgrade an Oracle Multitenant environment:
The interesting case happens in the “Everything At Once“.… [Read More]