Infrastructure at your Service

All posts by Franck Pachot

Franck Pachot
Technology Leader
Principal Consultant

OCM 12cFranck Pachot has 20 years of experience in Oracle databases. Through his expertise as a DBA, Oracle expert, data architect, and performance specialist, he is able to cover all database areas: architecture, data modeling, database design, tuning, operation, and training. Franck knows how to enable an efficient collaboration between the developers and the operational team when it comes to troubleshooting issues or performance tuning.

RSSOracle ACEOracle ACE Franck is Oracle Certified Master (OCM 12c), Oracle ACE Director and proud member of Oraworld-team and Oak Table.

Next public appearance:
SOUG
Swiss Oracle User Group

Leman: Calculer les statistiques comme prévu par l'optimiseur
Baden: Single-Tenant 12.2
OOW17
San Francisco, Oct 1st

Multitenant: Trust It by Understanding Beyond What Is Documented
DOAG2017
Nürnberg, Nov, 21st

Multitenant internals
UKOUG TECH17
From Transportable Tablespace to Pluggable Databases
Join Methods: Nested Loop, Hash, Sort, Merge, Adaptive
C15LV
Las Vegas , Apr 25th

From Transportable Tablespaces to Pluggable Databases
12.2 Multitenant New Security Features to Clarify DevOps and DBA role separation


Franck Pachot

Unplug an Encrypted PDB (ORA-46680: master keys of the container database must be exported)

By | Oracle | No Comments

In the Oracle Database Cloud DBaaS you provision a multitenant database where tablespaces are encrypted. This means that when you unplug/plug the pluggable databases, you also need to export /import the encryption keys. You cannot just copy the wallet because the wallet contains all CDB keys. Usually, you can be guided by the error messages, but this one needs a little explanation and an example.  

 
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Franck Pachot

Spectre/Meltdown on Oracle Public Cloud UEK – PIO

By | Oracle | 2 Comments

The Spectre and Meltdown is now in the latest Oracle UEK kernel, after updating it with ‘yum update': [opc@PTI ~]$ rpm -q –changelog kernel-uek | awk ‘/CVE-2017-5715|CVE-2017-5753|CVE-2017-5754/{print $NF}’ | sort | uniq -c 43 {CVE-2017-5715} 16 {CVE-2017-5753} 71 {CVE-2017-5754} As I did on the previous post on AWS, I’ve run quick tests on the Oracle Public Cloud.  

 
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Franck Pachot

Keep your orapw password file secure

By | Oracle | 2 Comments

This is a small demo I did when I’ve found a database password file (orapw) lying around in /tmp with -rw-rw-rw- permissions, to show how this is a bad idea. People think that the orapw file only contains hashes to validate a password given, and forget that it can be used to connect to a remote database without password.  

 
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Franck Pachot

12c Multitenant internals: PDB replay DDL for common users

By | Oracle | No Comments

In multitenant, you can create common Users, Roles, and Profiles. You create them in CDB$ROOT, with the CONTAINER=ALL clause (which is optional because it is the only possible value when connected to CDB$ROOT) but they are visible to all containers. As the goal of multitenant is to avoid to duplicate common metadata to all containers, You may think that they are visible through those magic metadata links. But that’s actually wrong: they are simply replicated…

 
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Franck Pachot

Drop PDB including datafiles may keep files open

By | Oracle | No Comments

I like that Oracle drops the datafiles from the operating system when we remove them from the database (with drop tablespace or drop pluggable database) because I don’t like to have orphean files remaining in the filesystem. However, to ensure that space is reclaimed, we must be sure that Oracle did not leave a process with this file opened. Linux allows to drop an open file but then drops only the inode. The consequence is…

 
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Franck Pachot

12cR2 Subquery Elimination

By | Oracle | No Comments

More and more we can see crazy queries generated by ORM frameworks or BI query generators. They are build to be easily generated rather than being optimal. Then, the optimizer has to implement more and more transformations to get an efficient execution plan. Here is one new that appeared in Oracle 12cR2: Subquery Elimination when the subquery do not filter any rows.  

 
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Franck Pachot

Oracle docker image from docker store

By | Oracle | No Comments

Did you notice that each time you want to download the Oracle binaries from the OTN website (for non-production usage) you have to click on the “Accept License Agreement”? This is because you have to agree with the OTN license agreement, and that makes it not easy to distribute an automated way to build an environment. The only exception I have seen was the sealed envelopes provided for the RACattack:  

 
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