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12c Release 1

Creating a 12c Container Database from scripts

If you are curious how to create a CDB without the help of dbca then the “generate scripts” option is exactly the right approach! I am a great fan of creating databases with the required options only-the default template (General Purpose) is dangerous as it creates a database with options you may not be licensed for and additionally opens security risk.

The best^H^H^Heasiest way to understand how a Container Database (CDB from now on) is created is to let dbca create the scripts. The process is the same as with an interactive installation except that at the very end you do NOT create the database but tick the box to generate the scripts.

The resulting scripts will be created in $ORACLE_BASE/admin/${ORACLE_SID}/scripts. Change directory to this location and you will be surprised about the sheer number of files ending in *.sql

Adding a node to a 12c RAC cluster

This post is not in chronological order, I probably should have written something about installing RAC 12c first. I didn’t want to write the tenth installation guide for Clusterware so I’m focusing on extending my two node cluster to three nodes to test the new Flex ASM feature. If you care about installing RAC 12c head over to RAC Attack for instructions, or Tim Hall’s site. The RAC Attack instructions are currently being worked at for a 12c upgrade, you can follow/participate the work on this free mailing list.

The cluster I installed is based on KVM on my lab server. I have used Oracle Linux 6.4 with UEK2 for the host OS. It is a standard, i.e. not a Flex Cluster but with Flex ASM configured. My network configuration is as shown:

Oracle Automatic Data Optimisation 12c

One of the seriously cool new features in the Oracle database 12c is the automated lifecycle management option. I freely admit you can get the same with other storage vendors (EMC FAST VP is the one I know first hand, but 3PAR and others have similar technology) but this is not really an option for the Oracle Database and Exadata. A quick word of warning: I have not even opened the licensing guide for 12c yet, this may well be a cost option so as always please ensure you are appropriately licensed before using this feature.

Why this post

The official documentation-VLDB and Partitioning Guide, chapter 5-is a bit lacking, as is the SQL Language Reference, hence this post.

Flex ASM 12c in action

I have been working on Flex ASM for a little while and so far like the feature. In a nutshell Flex ASM removes the requirement to have one (and only one!) ASM instance per cluster node. Instead, you get three ASM instances, not more, not less-regardless of cluster size.

Databases which are in fact “ASM clients” as in v$asm_client connect remotely or locally, depending on the placement of the ASM instance and the database instance.


Sometimes it’s the little differences that make something really cool, and I was wondering why this hasn’t made it into the Oracle dictionary before.

Have you ever asked yourself which out of the 30 or so accounts in the database were maintained by Oracle or in other words were Oracle internal and to be left alone? I did so on many occasions especially when it comes to the options I do not regularly see in the database. DBA_USERS lists all accounts in the database, user managed as well as Oracle managed. The below is the definition of the 11g view:

Your first steps with the multi-tenancy option

You can’t possibly have avoided all the buzz around the multi-tenancy option until now so it is probably in order to give you a bit more information about it besides the marketing slides Oracle has shown you so far.

IMPORTANT:This article is a technical article and leaves the pros and cons for the multi-tenancy option at one side. It does the same with the decision to make the CDB a cost option. And it doesn’t advise you on licensing either, so make sure you are appropriately licensed to make use of the features demonstrated in the series.

Series Overview

Since it is nearly impossible to give an overview over Pluggable and Container Databases in one article this is going to be a series of multiple articles. In this part you can read about creating PDBs and where to look for information about them.