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Little things worth knowing: Executing RDA on RAC

Result! I have finally been able to gather a complete RDA (Oracle Remote Diagnostic Agent) output on my 2 node RAC system. After consulting the relevant documentation on MOS-which is spread over at least 42 Doc IDs-I found them not to be very helpful to the degree that some of what I read is actually wrong or contradicting. I put together a short note, primarily to myself, to remind me of the process. I hope you find it useful, too.

The RDA version I used for this post is 8.14.x from MOS March 4th 2017. My RAC nodes are based on Oracle Linux 7.3/UEK 4.

Starting the data collection

12c Release 2 – Transparent Data Encryption online !

It doesn’t take a rocket scientist to know that even if you have incredibly stringent controls on user authentication, user authorisation etc, that wont save you if your data on disk is not encrypted.  All you need is an errant tape, a missing disk, a misplaced flash stick…and kersplat, someone has a copy of your datafiles from your Oracle database.

Data at rest should be encrypted, but that often meant taking applications offline to do so.

I’ve put my Speed Racer hat on Smile and here’s a video on a new 12c Release 2 feature covered in 60 seconds !

New theme – it was about time

After a lot of searching and testing I have finally decided to put the ageing Andreas09 theme a rest and try a new one. It has been nagging me for years that the representation of the blog is more like the early 2000s than 201x. Or was it late 1990s? Anyway, out with the old, in with the new.

The biggest problem I have with finding suitable templates is a) that I have insufficient talent in the fine arts, and b) that I present a lot of code examples. I guess point a) can’t be helped much, but b) had to be reasonably taken care of.

The monospaced font I use in the code blocks is usually far too large-10pt or more-in most themes that I otherwise liked a lot. The current one seems to use 10pt at maximum which is a good compromise although I would have preferred 9pt. My favourite font family for coding since my MacOS 7 days is Monaco, 9pt. I wish :)

TimTams, Twelve Two, and tete-a-tete !

What do you do when

  • you’re an Australian,
  • you’re at Oracle Headquarters, 13,000 kms from home
  • you bump into someone whilst grabbing a coffee

Well…naturally, you lure them over with a packet of our famous Australian chocolate biscuits, grab a camera and have a chat !

Maria Colgan and I chew the fat over why you should upgrade to Oracle Database 12c (including Release 2)

Oracle Database 12c Release 2 is here !

image

Since OpenWorld 2016 when we first saw some of the cool features in Oracle Database 12c Release 2, many IT professionals out there have been exploring the release via our various cloud offerings, but if your organization has not yet embraced the cloud, then March 2017 is a great month for you !  Because you can now download the latest and greatest release of our database from the usual downloads page, and run it on your own servers in your own data centre.

Example Jmeter workload for Postgres and Oracle

pgload.jmx is JMX file you can load into Jmeter and run a substantial load on a Postgres database. Should work just as well on Oracle if you change the test SQL from “Select 1″ to “select 1 from dual”

Install jmeter on our machine . On my mac, I did

  • brew install jmeter

You will need the Postgres driver. I used

jmeter1

Better to be safe than sorry…

I’ve always been worried about taking a script that is fine to run in my non-production environments (in particular a DROP script) and accidentally running it in a Production environment, shortly followed by the typing up of a fresh resume to look for a new job once the mistake is discovered Smile

DDL triggers – interesting results

This question came in on AskTom, yielding a very interesting result when it comes to DDL triggers. To set the scene, I’ll first create a table called T which is just a copy of SCOTT.EMP

Duplicate constraints are impossible right ?

Here’s a very simple example of a table called PARENT being a (surprise surprise) parent in a referential integrity relationship to a (drum roll for my choice of name) CHILD table


SQL> create table parent ( p int, constraint PAR_PK primary key (p) );

Table created.

SQL> create table child ( c int,
  2        p int
  3      );

Table created.

SQL> alter table child add constraint fk1 foreign key ( p ) references parent ( p );

Table altered.

That is all as we would expect, and similarly, if I inadvertently try to add the same foreign key constraint, I’ll get an error