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US Senate Candidate Mark W. Farnham speaks on Manchester Public TV

Here is the link.

 

 

AZORA Rises Like the Phoenix!

The Arizona Oracle User Group (AZORA) was reincarnated Tuesday July 29 by a group of six Oracle specialists interested in focusing the Oracle User Community in Arizona. A board was elected and began review of the organization bylaws (dated 1990) to be completed and presented at AZORA’s inaugural Educational Workshop tentatively scheduled for October. The new board includes: President, John King (King Training Resources); Vice-President Danny Carrizosa (OneNeck IT Solutions), Treasurer, Raj Chotalla (Intel), Secretary, Carlos Aquilar (GoNet USA), and Past-President Stephen Andert (IBM). Two of AZORA’s past presidents Steve Lemme (Oracle) and Stephen Andert (IBM)  are actively involved and lending their experiences and expertise. Visit the “AZORA – Arizona Oracle User Group” LinkedIn page to learn more.

Who deserves the title “Expert” or (even worse) “Guru”?

I wanted to expand on a thread in a LinkedIn group I’m part of, where one of the members wrote “It’s funny when 2 experts are arguing about who is better”, using Tom Kyte and Jonathan Lewis as examples of people they say are “Experts”.

Disclaimer: I have not spoken to Jonathan or Tom in regard to their viewpoints on this subject, so this shouldn’t be taken as them saying any of this, just my interpretation.

My perspective on that is I think you will rarely find two people who deserve the title of “Expert” will argue about “who is better”.  They would discuss the technical merits of a point instead.  In fact, most people I know that are generally accepted as “experts” really don’t believe they are, and most of them REALLY don’t like the term “Guru”.

MERGE and IOT’s ….. unhappy bedfellows

Anyone who has used Oracle for a while will be familiar with the Parent/Child locking "issue" when it comes to tables and indexes on foreign keys.  For many years you’d hear people crying "bug" etc but thankfully most now know the reason, and accept it as sensible behaviour.

But lets take a look at a slight variation on that theme.

Lets start with a table called "LOC" which will be our parent table in this example. Note that it is an IOT, and we’ll also have a child table "LOC_CHILD", which is also an IOT.

Can you justify your data ?

People ask me to justify use of Delphix. I can understand. Delphix is pretty new and often, most of my friends who are DBAs respond with “I can copy a database, so what, I can do it a little faster with Delphix.” Well that’s missing the whole boat. The question won’t be why you should use Delphix but “can you  justify working without Delphix?”

I see Delphix as amazingly positioned at nexus of data concerns right now – the right place at the right time :

What is Delphix ? (video presentation)

#555555;">According to a recent IDC study, on average Delphix

  • pays for itself in 4.3 months
  • 461% ROI over 5 years
  • 96.8% reduction in database storage
  • $50 Million predicted annual benefit for organizations over 75,000 employees

#555555;">Delphix is used by over 100 of the Fortune 500.

#555555;">What is Delphix? Why is Delphix important? What problems does Delphix solve in the industry?

#555555;">Here is a slide deck I put together for KSCOPE :

12c – Nested tables vs Associative arrays

This was going to the be the immediate follow up to my previous post, but 12.1.0.2 came out and I got all excited about that and forgot to post this one :-)

Anyway, the previous post showed how easy it is to convert between nested tables and associative arrays.  The nice thing in 12c is that this is no longer needed – you can query the associative arrays directly

12.1.0.2 security grrr…

One of my favourite security "tricks" used to be the following:

SQL> [create|alter] user MY_USER identified by values 'impossible';

Looks odd, but by setting the encrypted value of someone’s password to something that it is impossible to encrypt to, means you’ll never be able to connect as that account.  (Think schema’s owning objects etc).

I hear you ask: "Why not just lock the account?"

Well…in my opinion, that’s a security hole.  Let’s say Oracle publishes a security bug concerning (say) the MDSYS schema.  As a hacker, I’d like to know if a database has the MDSYS schema.  All I need do is:

SQL> connect MDSYS/nonsense

Why is that a security hole ?  Because I wont get "Invalid username or password".  I’ll get "ORA-28000: the account is locked" and voila…Now I know that the MDSYS user is present in that database.

ASH visualized in R, ggplot2, Gephi, Jit, HighCharts, Excel ,SVG

There is more and more happening in the world of visualization and visualizing Oracle performance specifically with v$active_session_history.

Of these visualizations,  the one pushing the envelope the most is Marcin Przepiorowski. Marcin is responsible for writing S-ASH , ie Simulated ASH versions 2.1,2.2 and 2.3. See

Here are some examples of what I have seen happening out there in the web with these visualizations grouped by the visualization tool.

To subset or not to subset

There was a problem at a customer in application development where using full copies for developers and QA was causing excessive storage usage and they wanted to reduce costs , so they decided to use subsets of the production development and QA
  • Data growing, storage costs too high, decided to roll out subsetting
  • App teams and IT Ops teams had to coordinate and manage the complexity of the  shift to subsets in dev/test
  • Scripts had to be written to extract the correct and coherent data, such as correct date ranges and respect referential integrity
  • It’s difficult to get 50% of data 100% of skew instead of  50% of data 50% of skew
  • Scripts were constantly breaking as production data evolved requiring more work on the subsetting scripts
  • QA teams had to rewrite automated test scripts to run correctly on subsets
  • Time lost in ADLC, SDLC to enable subsets to work (converting CapEx into higher OpEx) put pressure