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Pluggable Databases

Any reason to change the C## common user prefix?

By Franck Pachot . In 12.1.0.1 the common user prefix was set to C## by an underscore parameter. In 12.1.0.2 it’s a documented parameter and you can change it. But is there any reason for that? I can think of a reason. Let’s say I want to use external authentication for my common users SQL> show parameter prefix   NAME… 

awrrpt and spreport in multitenant

By Franck Pachot . Yesterday I was giving my ‘Interpreting AWR Reports’ Prezi at Oracle Midlands. There is a point where I explain that I always check the ‘Captured SQL account for …% of Total DB Time (s)’ in order to know whether I’ll get all details in the report or not. There are two main reasons why the most… 

PDB Snapshot using dbms_dnfs.clonedb_renamefile

By Franck Pachot . In the previous post I’ve explained how to use ‘snapshot copy’ PDB creation for thin provisioning and quick restore of initial state for continuous integration tests. If you don’t have the multitenant option, you need a remote CDB to do it. Here is a way to do the same on only one single-tenant CDB. The idea… 

PDB snapshot copy for continuous integration testing

By Franck Pachot . How do you manage your continuous integration tests on the database? You need to restart at the same state for probably a hundred of tests. Recreating the schema and test data takes too long. Oracle is not optimized for DDL. Restoring the database takes too long. Even if you data is small, there is those SYSTEM,… 

Phantom session environment in multitenant?

By Franck Pachot . In multitenant a session can switch from one container to another. There are a few restrictions such as a transaction cannot span multiple containers. But how do sessions parameters behave? It seems that there is a small inconsistency. I was looking at some adaptive plan and SPM behavior (see this tweeter conversation) and played with the… 

OCM 12c preparation: RAT in multitenant

By Franck Pachot . I have several customers that have cases where Real Application Testing can be interesting, but they don’t use it because it’s an expensive option. Which is why it’s probably the topic listed for OCM 12c exam where I’ve the less experience. And I don’t even know at which level (CDB or PDB) it has to be… 

OCM 12c preparation: documentation

By Franck Pachot . The OCM exam advice says: Be prepared to use the non-searchable documentation during the exam, to help you with correct syntax. I’ve checked that I can find quickly the documentation related with each topic listed. Here it is As in the previous posts, I write that before taking the exam, from only the list of topics,… 

OCM 12c preparation: Transportable Tablespaces

By Franck Pachot . I use transportable tablespaces a lot since 8i, here are just a few examples. Same disclaimer here as in the first post of the series: don’t expect to get those posts close to what you will have at the exam, but they cover important points that matches the exam topics. Documentation Information about the exam says:… 

OCM 12c preparation: Manage PDB

By Franck Pachot . Let’s see the different ways to create a PDB, with different tools. Same disclaimer here as in the first post of the series: don’t expect to get those posts close to what you will have at the exam, but they cover important points that matches the exam topics. Documentation Information about the exam says: Be prepared… 

OCM 12c preparation: Create CDB in command line

By Franck Pachot . This post starts a series about things I wrote while preparing the OCM 12c upgrade exam. Everything in those posts are written before taking the exam – so don’t expect any clue about the exam here. It’s based only on the exam topics, and only those points I wanted to brush up, so don’t expect it… 

11.2.0.4 support? Don’t worry until 2017

By Franck Pachot . Customers reluctant to go to 12c before 12.2, in addition to Standard Edition contract changes when going to 12c, has lead to lot of upgrades to 11.2.0.4 but what about support? Don’t worry. It’s supported for no additional cost until May 2017 Support levels Do you know why you pay support (per year about 20% of… 

Multitenant vs. schema based consolidation

By Franck Pachot . If you want to install multiple instances of a software, for example you host the ERP for several companies or subsidiaries, you have 3 solutions: have one database and multiple schema have multiple databases have one database and multiple pluggable databases Of course, this is exactly the reason for pluggable databases: multitenant. You have good isolation…