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.

Cracow (PL), Sept. 1st

12cR2 Statistics Advisor: Do you gather statistics in the way the optimizer expects them?
Swiss Oracle User Group

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

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

Multitenant internals
From Transportable Tablespace to Pluggable Databases
Join Methods: Nested Loop, Hash, Sort, Merge, Adaptive

Franck Pachot

Dynamic Sampling vs. Extended Statistics

By | Oracle | No Comments

On datawarehouse databases, I frequently recommend increasing the level of dynamic sampling because: Queries have complex predicates with AND, OR, IN(), ranges and correlated values for which the optimizer cannot estimate the cardinality properly Queries are long anyway (compared to OLTP) and can afford more parse time to get an optimized execution plan However, there’s a drawback with this approach because sometimes the dynamic sampling estimation may give bad estimations, and supersedes the static statistics…

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Franck Pachot

Multitenant internals: INT$ and INT$INT$ views

By | Oracle | No Comments

This month, I’ll talk – with lot of demos – about multitenant internals at DOAG conference. The multitenant dictionary architecture starts with a simple idea: system metadata and data are in CDB$ROOT and user metadata and data are in PDB. And it could have been that simple. When a session connected to a PDB needs to read some system information, the session context is switched to the CDB$ROOT container and reads from CDB$ROOT SYS tablespace…

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Franck Pachot

Database is more than persistence. It is shared. My thoughts about Microservice Database.

By | Oracle | 4 Comments

The development teams often see the database as a ‘persistence layer’ only. And sometimes it is mentioned that the database is always the cause of the problems, especially when implementing continuous integration and trying to be agile. Then cames the idea to have this ‘persistence layer’ in an isolated environment, such as a docker container, with the database for each developer. However, this overlooks the real cause of the problems, which is not the persistence…

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Franck Pachot

Archivelog deletion policy on Data Guard configuration

By | Oracle | No Comments

The deletion policy on a dataguard configuration should be: CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON ALL STANDBY; for the site where you don’t backup. It can be the standby or the primary. and: CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON ALL STANDBY BACKED UP 1 TIMES TO DISK; for the site where you do the backups. It can be the primary or the standby. I’ve always configured it in this way, but I recently…

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Franck Pachot

VirtualBox 5.2 exports the VM to the Oracle Cloud

By | Database Administration & Monitoring | No Comments

The new release of Oracle VM VirtualBox (aka VirtualBox) is there with a new functionality to export a VM to the Oracle Cloud Compute (aka Oracle Cloud Infrastructure). That can be interesting to prepare a VM on my laptop and move it to the Cloud to get it accessible from everywhere. Here’s my first try. In my opinion, it’s idea but probably need further evolution.  

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