Category: Uncategorized

Oracle Influencers

At the recent Oracle AI World 2025, I spoke to a gentleman about Oracle influencers.

He wanted to expand his knowledge on Oracle database tech and wanted to follow relevant people from Oracle.

I wanted to share the list with you in case you’d like to follow some of them as well.

Blogs

Here’s a list of personal blogs from people at Oracle from my own blog feed:

Am I missing someone? Please drop a comment, so that I can update the list (and my own blog roll 😎).

You can also find a long list of official blogs at Oracle.

YouTube

Here are the channels that I subscribe to:

What other channels am I missing?

Sharing

There are many influencers who are not affiliated with Oracle. They are certainly worth following as well. However, the assignment was to identify Oracle employees only.

Thanks to all of you out there who share knowledge with the Oracle community.

#SharingIsCaring

Oracle AI World – Come Say Hi!

In little more than a month, Oracle AI World 2025 starts in Las Vegas.

If you want to stay updated on Oracle Database upgrades, migrations and patching, here is a list of our sessions.

There’s so much to see at Oracle AI World, so start planning today.

Our Sessions

Our Hands-On Labs

How Do I Get A Seat?

The seats are on first-come-first-served basis. You can’t secure a seat upfront. You must show up in good time if you want to be sure to get a seat.

I Have Questions?

You can connect with us at our booth in the exhibition area.

Bring your questions, thoughts, ideas or enhancement requests. We’re all ears.

See you soon!

AutoUpgrade New Features: A Very Easy Way To Generate A Config File

I use AutoUpgrade everyday. Wake me up in the middle of the night and I can write one for you in the dark.

… But it might not be the case for everyone.

So, here’a quick way to generate an AutoUpgrade config file.

Auto Config

  1. Set the environment to the Oracle Database you want to patch or upgrade:
    $ env | grep ORA
ORACLE_SID=UPGR
ORACLE_BASE=/u01/app/oracle
ORACLE_HOME=/u01/app/oracle/product/19
  2. Call AutoUpgrade with -auto_config parameter:
    java -jar autoupgrade.jar -auto_config
    • You can also specify the database using the -sid <mydb> parameter.
  3. AutoUpgrade creates a sample config file named auto_config.cfg.
    • It is a basic config file with the most essential parameters already filled out from the environment, like sid, source_home and logging directories.
    • If you have multiple candidate Oracle homes, AutoUpgrade adds all of them as a comment, and you can easily select the one you want
      #upg1.target_home=/u01/app/oracle/product/21
#upg1.target_home=/u01/app/oracle/product/23
    • All other parameters are added as comments with a description on their usage. You can uncomment those that you need.
  4. Use AutoUpgrade to patch or upgrade your Oracle Database.

Final Words

If you need a more elaborate config file, you can also try Marcus’ AutoUpgrade Composer.

Happy AutoUpgrading!

How To Downgrade a PDB from Oracle Database 23ai

When talking about upgrades, Oracle Database has a great fallback mechanism; a downgrade. Even after going live on Oracle Database 23ai, you can get back to Oracle Database 19c or 21c – with no data loss.

How to Downgrade From Oracle Database 23ai

My PDB, PDB1, has already been upgraded to Oracle Database 23ai. Now, I want to downgrade to Oracle Database 19c. In the downgrade process, I will unplug from CDB23 and into CDB19.

  1. I open the PDB in downgrade mode:
    alter pluggable database PDB1 close immediate;
alter pluggable database PDB1 open downgrade;
    • Downgrade mode is a special mode – similar to upgrade mode. It enables exclusive access to the database and disables a lot of features.
  2. I set the environment to CDB23 and start the downgrade process:
    cd $ORACLE_HOME/bin
./dbdowngrade -c 'PDB1'
    • The -c command line parameter starts a downgrade of a specific PDB; not the entire CDB.
  3. After the downgrade, I close and unplug from CDB23:
    alter pluggable database PDB1 close;
alter pluggable database PDB1 unplug into '/home/oracle/scripts/pdb1.xml';
  4. Now, I connect to CDB19 running on Oracle Database 19c. I plug in and open the PDB in upgrade mode:
    create pluggable database PDB1 using '/home/oracle/scripts/pdb1.xml';
alter pluggable database PDB1 open upgrade;
  5. I switch to PDB1 and complete the downgrade by running the catrelod.sql script:
    alter session set container=PDB1;
@$ORACLE_HOME/rdbms/admin/catrelod.sql
  6. Then, I recompile all invalid objects:
    @$ORACLE_HOME/rdbms/admin/utlrp.sql
  7. A restart of the PDB. I open in normal mode:
    alter pluggable database PDB1 close;
alter pluggable database PDB1 open;
  8. I gather new dictionary statistics:
    exec dbms_stats.gather_dictionary_stats;
    • After a while, when the database is warmed up, I also gather fixed objects statistics.
  9. I verify that all components are VALID or OPTION OFF:
    select comp_id, version, status from dba_registry;
  10. I run Datapatch to ensure all SQL patches are properly applied:
    $ORACLE_HOME/OPatch/datapatch

That’s it!

Worth Knowing About Downgrades

  • The downgrade is a two-step process.

    • The first part happens while the database is running in the new Oracle Home. Startup in a special downgrade mode and execute catdwgrd.sql to start the downgrade.
    • Next, restart the database in the old Oracle Home and start in upgrade mode. catrelod.sql will re-install any missing objects in the database and finish the downgrade.

  • Oracle recommends that you install the latest Release Update in both Oracle homes; the one that you downgrade from, and the one to which you downgrade.

  • You can only downgrade if the compatible hasn’t been changed after the upgrade.

  • If the timezone file was upgraded, the same timezone file must be present in the old Oracle Home.

  • Before you start the downgrade, there’s no need to roll off any patches with Datapatch. The downgrade mechanism takes care of that.

  • The data dictionary in a downgraded database is not identical to the pre-upgraded database. The data dictionary will be different, but compatible. Here are some examples:

    • Generally, dropping objects is avoided.
    • New tables are most likely not dropped but truncated.
    • New indexes are most likely kept.

  • Although you can downgrade a database from Oracle Database 23ai to 19c, you can’t undo the multitenant migration. To get back to a non-CDB you must use other means like Data Pump, transportable tablespaces, or GoldenGate.

Want to Try?

Hopefully, you never need to downgrade a PDB. But I bet you can resist the urge to try it. Right? RIGHT?

In our hands-on lab, Hitchhiker’s Guide for Upgrading to Oracle Database 23ai, there is a downgrade exercise. Give it a try. The lab is free to use and doesn’t require any installation – it runs completely inside a browser.

Happy downgrading!

Appendix

Further Reading

Can I Use the Oracle Database 23ai Preinstall RPM for Oracle Database 19c?

A customer asked me:

My ops team wants to use the Oracle Database 23ai preinstallation RPM for all our new servers. For now, the servers will host Oracle Database 19c only. In the future, we will use Oracle Database 23ai on those servers as well.

The preinstallation RPM contains instructions on which packages to install and which system settings to set. According to the Oracle Database 19c Installation Guide for Linux, this is how you run it:

dnf install oracle-database-preinstall-19c

Let’s find out whether you can use the 23ai preinstallation RPM for 19c.

Inspecting the Package

  • I use an Oracle Linux 8 test system. First, I install both packages:

    dnf -y install oracle-database-preinstall-19c
dnf -y install oracle-database-preinstall-23ai

  • Next, I look at the files in the 19c RPM:

    rpm -ql oracle-database-preinstall-19c

/etc/rc.d/init.d/oracle-database-preinstall-19c-firstboot
/etc/security/limits.d/oracle-database-preinstall-19c.conf
/etc/sysconfig/oracle-database-preinstall-19c
/etc/sysconfig/oracle-database-preinstall-19c/oracle-database-preinstall-19c-verify
/etc/sysconfig/oracle-database-preinstall-19c/oracle-database-preinstall-19c.param
/usr/bin/oracle-database-preinstall-19c-verify
/usr/share/licenses/oracle-database-preinstall-19c
/usr/share/licenses/oracle-database-preinstall-19c/LICENSE
/var/log/oracle-database-preinstall-19c
/var/log/oracle-database-preinstall-19c/results

  • The file oracle-database-preinstall-19c.param contains the settings, groups, and users. In the 23ai RPM, there is a similar file, oracle-database-preinstall-23ai.param. I can compare the two files to see any differences:

    #Remove comments before comparing
sed '/^\(#\|kernelcomment\|usercomment\)/d' /etc/sysconfig/oracle-database-preinstall-19c/oracle-database-preinstall-19c.param > /tmp/19c.params
sed '/^\(#\|kernelcomment\|usercomment\)/d' /etc/sysconfig/oracle-database-preinstall-23ai/oracle-database-preinstall-23ai.param > /tmp/23ai.params

diff /tmp/19c.params /tmp/23ai.params

  • Then, I can analyze the differences. < is the 19c setting, > is the 23ai setting.

    28c28
< kernel:*:*:*:net.ipv4.ip_local_port_range:9000 65500
---
> kernel:*:*:*:net.ipv4.ip_local_port_range:9000 65535
    • Port range extended in 23ai.
    52,53c52
< boot:x86_64:*:*:*:numa:off
< boot:*:*:*:*:transparent_hugepage:never
---
> boot:*:*:*:*:numa:off
> boot:*:*:*:*:transparent_hugepage:madvise
    • NUMA off for all architectures. Not a big deal, as this is Oracle Linux and Oracle Database runs on 64-bit architecture only.
    • But there is a change in the setting for transparent hugepages. Knowing how much havoc transparent hugepages have caused, this is an important change. I’ll get back to that.
    63a63,64
> kernel:*:*:*:kernel.panic:10
    • Adding a kernel panic setting. Shouldn’t cause any concern.

Transparent Hugepage

  • The setting for transparent hugepages changes from never to madvise. In this setting, the kernel only assigns huge pages to application processes that explicitly request huge pages through the madvise() system call (ref. Oracle Linux 8 – Configuring Huge Pages).

  • The 23ai installation guide lists:

    For optimal performance, Oracle recommends that you set Transparent HugePages to madvise on all Oracle Database servers UEK7 and later kernels and not disable Transparent HugePages as was recommended in prior releases.

  • Let me check my kernel version:

    uname -r

5.15.0-307.178.5.el8uek.x86_64
    • el8uek means my kernel is UEK8, so I can use the new setting on this system.

  • But I will use this server for Oracle Database 19c and 23ai, so can I use the new madvise setting?

    Transparent huge page memory is enabled by default on Oracle Linux and Exadata. The ‘madvise’ parameter used in the kernel command enables transparent huge pages and assigns huge pages to memory regions explicitly requested by applications using the madvise system call. In the case that Oracle Database 19c and 23ai are running on the same server, Oracle recommends setting transparent huge pages to ‘madvise’.

    Huge Pages or Transparent Huge Pages in Context of Exadata

  • So, it should be safe to run with the new setting for Oracle Database 19c. If you are concerned, you can revert to never until you install Oracle Database 23ai.

Packages

  • I can find the dependencies of the two preinstallation RPMs:
    rpm -qR oracle-database-preinstall-19c > /tmp/19c.pkgs
rpm -qR oracle-database-preinstall-23ai > /tmp/23ai.pkgs
  • Then, I can find the difference:
    diff /tmp/19c.pkgs /tmp/23ai.pkgs
  • There are many differences because the 23ai RPM now lists minimum versions for many packages. Assuming that you automatically install the latest version of the packages, I will disregard those differences.
  • This brings me to this list. These dependencies are not part of the 23ai RPM:
    ethtool
libaio-devel
libnsl
libstdc++-devel
openssl-libs
    • I would need to install those manually if I wanted to use the 23ai RPM.
  • For completeness, these are the new packages in the 23ai RPM:
    fontconfig >= 2.13.1
policycoreutils
policycoreutils-python-utils

Conclusion

You can use the 23ai preinstallation RPM if you take care of the missing packages.

I recommend running both preinstallation RPMs instead in the listed order:

dnf install oracle-database-preinstall-19c
dnf install oracle-database-preinstall-23ai

Then, you proceed with installation of Oracle homes using AutoUpgrade.

Happy installing!

Appendix

Credits

A thank-you to Rodrigo Jorge for helping with this article.

Oracle DatabaseWorld

While you wait for the big show in Las Vegas later this year, here’s something to whet your appetite.

Oracle DatabaseWorld Multicloud AI Edition

Hit the Watch on demand button to get free access to all these sessions and get up-to-date on Oracle Database. You can watch the videos anywhere and anytime.

What’s On

Get an overview with the keynotes or dive into the details in specialized sessions.

  • Take a look into at crystal ball and hear about Oracle’s vision for data and AI. Our Executive Vice President, Juan Loaiza, shares how Oracle Database’s cutting-edge converged data architecture helps customers bring AI to data.

  • Also, there are three track keynotes giving you further details on different topics.

  • Mike Dietrich and I give you a head start on your upgrade to Oracle Database 23ai in our session Upgrade to Oracle Database 23ai: Best Practices and Customer Experience.

  • Plus, a number of other sessions that go into the details as well.

I Got Questions

If you need more information on upgrades to Oracle Database 23ai or have questions after watching our session, reach out to me and I’ll get you sorted.

You can also try upgrades in our hands-on lab. It’s free and runs in a browser – nothing to install. And – it’s better to fail in our lab, than in production.

Happy learning!

AutoUpgrade New Features: Install Oracle Home on Brand-New, Empty Server

You can use AutoUpgrade to install an Oracle home on a brand-new, empty server.

Previously, AutoUpgrade used an existing Oracle home to determine how to create a new Oracle home. Now, you can use config file parameters to instruct AutoUpgrade on installing the new Oracle home.

This allows you to use AutoUpgrade to prepare a new server for use with Oracle Database.

How To

Preparations

I start with a brand new Oracle Linux 8 system.

  1. This is a test system, so I disable SELinux:
    sed -i 's/^SELINUX=.*/SELINUX=disabled/' /etc/selinux/config
reboot
    • Alternatively, follow the guidelines for SELinux in your organization.
  2. Install the preinstall package and Java (required by AutoUpgrade):
    yum -y install oracle-database-preinstall-19c
yum -y install java-1.8.0-openjdk
  3. Additional configurations like mount points and swapfile.

Install Oracle Home

  1. Download AutoUpgrade:

    wget https://download.oracle.com/otn-pub/otn_software/autoupgrade.jar

  2. Create an AutoUpgrade config file called install-home.cfg:

    global.global_log_dir=/home/oracle/autoupgrade/logs
install1.patch=RU:19.27,OPATCH,OJVM,DPBP
install1.folder=/u01/app/oracle/software
install1.target_home=/u01/app/oracle/product/dbhome_1927
install1.home_settings.oracle_base=/u01/app/oracle
install1.home_settings.edition=EE
install1.home_settings.inventory_location=/u01/app/oraInventory
install1.download=no
    • I have already downloaded the base release and required patches using AutoUpgrade download mode. The files are in an NFS file share which I specify with the folder parameter.
    • I use the home_settings parameters to specify how I want to install the Oracle home. There are many other settings that I can use.

  3. I start AutoUpgrade:

    java -jar autoupgrade.jar -config install-home.cfg -patch -mode create_home

  4. On this system, the oracle user is not allowed to sudo, so I must manually execute the root scripts:

    /u01/app/oracle/product/dbhome_1927/root.sh
/u01/app/oraInventory/orainstRoot.sh
    • AutoUpgrade prints the scripts to the console.
    • It also writes the scripts into <global_log_dir>/create_home_1/<job-no>/rootsh/rootsh.log.

  5. That’s it! I’ve now installed a new Oracle home and can move on with the creation of a listener, database, and so forth

Appendix

Installing on Microsoft Windows

You can use the same functionality on Windows.

  • You must use home_settings.account_type to specify the user that runs the Windows service. If you specify a user, then it must exist already. Although runInstaller can create the user for you, AutoUpgrade doesn’t support it.
  • You should not use home_settings.inventory_location on Windows. On Windows, the Oracle Inventory is always placed in %SYSTEM_DRIVE%\Program Files\Oracle\Inventory.

Installing Java

AutoUpgrade requires Java 8 or Java 11. It doesn’t support newer versions because the tool must be backward compatible. The latest version of AutoUpgrade still supports upgrades from Oracle Database 11g.

I recommend using Oracle Java. This is what we test and develop with, however, other Java packs should be fine as well. I tested the commands in this blog post with OpenJDK.

If you have a license for Oracle Database, you can read about using Oracle JDK/JRE in the License Guide or Oracle Java SE licensing FAQ.

AutoUpgrade New Features: Include Monthly Recommended Patches When Patching

Staying even more up-to-date with Monthly Recommended Patches (MRP) is now easier when patching using AutoUpgrade.

MRP contains fixes from 555.1 conveniently bundled together in a single patch.

> To provide customers more frequent access to recommended and well-tested collections of patches, Oracle is pleased to introduce Monthly Recommended Patches (MRPs)

From My Oracle Support note ID 555.1

How To

  1. Get the latest version of AutoUpgrade:
    wget https://download.oracle.com/otn-pub/otn_software/autoupgrade.jar
  2. Add MRP to the patch entry in your AutoUpgrade config file:
    global.keystore=/home/oracle/autoupgrade-patching/keystore
patch1.source_home=/u01/app/oracle/product/19/dbhome_19_25_0
patch1.target_home=/u01/app/oracle/product/19/dbhome_19_26_0
patch1.sid=DB19
patch1.folder=/home/oracle/autoupgrade-patching/patch
patch1.patch=RECOMMENDED,MRP
  3. Run AutoUpgrade in analyze, download or deploy mode, and AutoUpgrade gets: * RECOMMENDED – latest available Release Update, OPatch, Data Pump Bundle Patch and OJVM Bundle Patch * MRP – latest available MRP matching the Release Update
  4. Optionally, you can add one-off fixes that are not part of the Release Update or MRP:
    patch1.patch=RECOMMENDED,MRP,34672698
    • You can add more one-off fixes using a comma-separated list

Tell Me More About Monthly Recommended Patches

Here’s a little snippet from Virtual Classroom #16: Oracle Database Release and Patching Strategy for 19c and 23ai, where Mike explains the concept.

I recommend that you also install MRPs when possible. Using AutoUpgrade, it’s really easy to add them, so why miss out?

Happy patching

Appendix

Further Reading

AutoUpgrade New Features: Using Proxy to Download Patches

Once you try the download mode in AutoUpgrade to get patches from My Oracle Support, you will never download patches in any other way. It’s so simple and so easy.

Post from Bluesky from a user of AutoUpgrade satisified with the new download mode Post on Bluesky

Suppose you need to connect through a proxy server to reach My Oracle Support and get the patches. AutoUpgrade now supports several ways to use a proxy.

Download Patches Through a Proxy

  1. Get the latest version of AutoUpgrade:

    wget https://download.oracle.com/otn-pub/otn_software/autoupgrade.jar

  2. Set the proxy settings in an environment variable before calling AutoUpgrade:

    export https_proxy=https://proxy.weyland-yutani.net:8080
java -jar autoupgrade.jar ... -mode download

    • Set https_proxy in lowercase. At least on Linux, environment variables are case-sensitive and although some programs can handle any case, it’s better to use the official case.

    • AutoUpgrade automatically picks up and uses the proxy.

Other Proxy Types

You can set https_proxy to a value matching this specification:

[https|http|socks5|socks]://(user_info@)site:port

  • Here’s an example of how to use SOCKS5 proxy:

    export https_proxy=socks5://proxy.weyland-yutani.net:8080

  • The user_info is optional. Here’s an example::

    export https_proxy=https://ellen:Olympia2092@proxy.weyland-yutani.net:8080

It Doesn’t Work

  • This error message indicates that you forgot to set the https_proxy environment variable or set it correctly:

    There were conditions found preventing AutoUpgrade Patching from successfully running

*Downloading Oracle Patch files
Patch query failed
*login-ext.identity.oraclecloud.com*

  • This error message indicates that your proxy doesn’t allow connections to all the required servers:

    There were conditions found preventing AutoUpgrade Patching from successfully running

*Downloading Oracle Patch files
Patch query failed
*Unable to tunnel through proxy. Proxy returns "HTTP/1.1 403 Forbidden"*

Required Connections

AutoUpgrade must connect to:

URLs are part of a CDN, so expect changing IP addresses. Use DNS names instead of IP addresses in your firewall/proxy configuration.

Happy patching!

Full-day Workshop in The Netherlands and Belgium

A year and a half ago, Mike Dietrich and I ran the Real World Upgrade and Migrate to Oracle Database 19c and 23ai workshop in Belgium and The Netherlands. Now, we’re returning with…

Advanced Real World Oracle Database Upgrade and Migration to 19c and 23ai

Perhaps not the most creative title for a sequel. But what the title lacks in creativity, we will compensate tenfold in content.

Workshop banner

If you’re interested in database tech, Mike and I invite you to join our workshops.

… a day full of technical best practices, tips, tricks and advices based on real world customer experience

The Agenda

Here are the topics that we will cover:

  • Release Strategy with Oracle Database 19c and 23ai
  • Oracle Database Patching – We are going to change the game!
  • New Features in AutoUpgrade
  • How to size, build and operate a Multitenant environment efficiently
  • Data Pump – The best new performance features and optimizations
  • Migrations for hands-on DBAs
  • Cross-platform migrations – Pushing the limits
  • Oracle Database 23ai Feature Update for DBAs and Developers

It’s all tech, no marketing!

When and Where

The workshops take place at the Oracle offices in Utrecht and Vilvoorde. We start at 09:00 and finish at 16:30 or when we’ve answered the last question.

The workshops are an in-person event. It’s not possible to join remotely.

Sign Up

The workshops are free, but registration is required.

Sign up for Utrecht and Vilvoorde.

Seats are limited, so sign up to secure your seat. If you can’t make it, please cancel your registration so a fellow geek can join instead.

I hope to see you there for a full day of fun!