Infrastructure at your Service

All posts by Franck Pachot

Franck Pachot
Technology Leader
Senior 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 ACE Franck is Oracle Certified Master (OCM 12c) and an Oracle ACE.

Next public appearance:
SOUG
Geneva (CH), May 19th

SOUG Training Day
Dbvisit
Lausanne(CH), June 2nd

dbi services replication event
SOUG
Düsseldorf (D), May 10-11th

Multitenant internals, Optimizer statistic gathering
SOUG
Baden(CH), June 23rd

Multitenant: trust it by understanding beyond what is documented


12cR2 Multitenant


Franck Pachot

SYS password on Oracle Cloud Service managed database

By | Database Administration & Monitoring | No Comments

When you create a DBaaS on the Oracle Cloud services you have to provide an administration password in the database configuration form. You do not need a password to connect to the VM. You use SSH key for it: on creation you provide the public key that will allow you to connect as the oracle user or the opc user (which can ‘sudo su’). But for the database you need to provide a password which…

 
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Franck Pachot

Adaptive Plan: How much can STATISTICS COLLECTOR buffer?

By | Database Administration & Monitoring | 7 Comments

The 12c adaptive plan prepares two join methods (Hash Join and Nested Loop), actives the one that has the better cost for the estimated cardinality and computes the point of inflection in cardinality estimation where the best cost changes to the other join method. At execution time, rows are buffered by a STATISTICS COLLECTOR operation in order to see if the point of inflection is reached. If it doesn’t, the plan continues as planned. If…

 
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Franck Pachot

When a query has read 350TB after 73K nested loops

By | Database Administration & Monitoring | No Comments

According that you have Tuning Pack, SQL Monitor is the right way to see what a query is currently doing. A query was running for days and the first figure I see is that it has read 350TB. This is not the kind of thing you do in only one operation, so I immediately checked the ‘executions’ columns: 73K table scans. So that’s finally only 5GB. The problem is not the full scan, but the…

 
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Franck Pachot

Testing Oracle on exoscale.ch

By | Database Administration & Monitoring | One Comment

My last post came from a discussion at SITB with exoscale. They are doing Cloud hosting with datacenters in Switzerland. In Switzerland a lot of companies cannot host their data outside of the country, which is a no-go for the big Cloud providers. After the discussion they gave me a coupon for a trial IaaS instance. And if you follow my blog you should know that when I have a trial access, there are good…

 
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Franck Pachot

Can you become a PaaS provider for an Oracle Database service?

By | Database Administration & Monitoring | No Comments

This post is not about technical limitations: Oracle Database is supported in most hypervisors (certified or not) so anybody can provide a DBaaS through a virtual machine as long as it run a supported OS, has enough CPU, memory, and storage, and open the required ports to access to the database (ssh and listener). But you cannot do what you want when you install a software, and you must agree with its licence terms. Who…

 
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Franck Pachot

A short glance at Attunity replicate

By | Database Administration & Monitoring | One Comment

If you follow my blog, you should know that I really like Dbvisit replicate because it’s simple, robust, has good features and excellent support. But that’s not a reason to ignore other alternatives (and this is the reason of http://www.dbi-services.com/news-en/replication-event-2/). When you have heterogeneous sources (not only Oracle) there is Oracle Golden Gate with very powerful possibilities, but maybe not an easy learning curve because of lack of simple GUI and setup wizard. You may…

 
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Franck Pachot

Transparently externalize BLOB to BFILE

By | Database Administration & Monitoring | No Comments

Storing documents within the database is the easiest, especially because you get them consistent with the metadata stored in the database. If you store them externally, then you need to manage their backup, their synchronization to standby site, the consistency in case of flashback or PITR, etc. However, documents grow (in number and in size thanks to better resolution of scan) and you don’t want a database where half of the size are documents in…

 
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