Oracle 11g: New Locking behavior (modes) … an unexpected behavior. Or?

I just noticed some strange locking behavior in one of our production databases.

It took me a while to reproduce this in test. I’ve based my example on Richard Foots blog “Oracle11g: New Locking Modes When Policing FK Constraints (A Wolf at the Door)”.

Continue Reading »

How PL/SQL can help improve your application design, and a lot more

ora_plsqlAs an Oracle resource taking part in development projects I’ve had the change to see how PL/SQL can actually increase the quality of both the application development and in application maintenance. In this article I’ll try to share this experience, and show how using PL/SQL will increase the quality of your application and your Oracle databases.

Continue Reading »

Speaking at Oracle OpenWorld 2014, San Francisco

presentationThe last  years I’ve attended Oracle OpenWorld every second year. And this year it’s again time to visit the big Oracle gathering in San Francisco. The big difference this year is that I’m going to be a speaker. Kind of scary, but I’m really looking forward to the experience. My session “Performance doesn’t happen by accident – Database performance for DBAs” was scheduled for Thursday at 09:30 at Marriott Marquis Hotel.

About 60000 attendees all together is rather impressive. But still it doesn’t feel to big. I meet friends and colleagues all over, and really get time to relax and enjoy between the sessions. And of course spend some time at the Exhibition Halls.

Continue Reading »

I’m speaking at Tech14 in Liverpool in December

TECH14_speakerI just got an email confirming my presentation “Performance doesn’t happen by accident: Database performance for developers” at UKOUG Tech14 in Liverpool in December. This is my first presentation in the UK, and my first time attending the Tech conference. I’m really looking forward to this experience.

I’m speaking at Oracle OpenWorld 2014, San Francisco, in September/October

oow-imspeaking-200x200-2225052I’ve just registered in this years OpenWorld conference in San Francisco in september. Last time I attended was in 2012. The news this year is that I’m going to be a speaker. My call for paper “Performance doesn’t happen by accident: Database performance for DBAs” just got accepted. Look for session id CON1918. Hope to see you at my presentation at the Oracle OpenWorld in September/October.

Isolation Levels by Tom Kyte

I just reread the Oracle Magazine article by Tom Kyte named “On Transaction Isolation Levels” from November 2005.
Great article that really explains why your relational database can not be treated as a black box.

From the article:
“The ANSI/ISO SQL standard defines four levels of transaction isolation, with different possible outcomes for the same transaction scenario. That is, the same work performed in the same fashion with the same inputs may result in different answers, depending on your isolation level. These levels are defined in terms of three phenomena that are either permitted or not at a given isolation level: Dirty Read, Nonrepeatable Read
and Phantom Read”.

This does not say anything about how this is implemented. Because of this the different implementations on different database systems makes them behave very differently regarding locking and concurrency mechanisms.

Read the article here

Submittet paper for the UKOUG Tech14

tech14This year I’ve submittet a paper for the Tech14 arranged by UKOUG in Liverpool in December 2014. My presentation is called “Performance does not happen by accident: Database performance for developers”, and I’ll be talking about the use of Oracle End-to-End Metrics. I imagine Liverpool in December will become a great experience, so hopefully my paper will be accepted.

OUGN 2014 & the “Mastering Oracle Trace Data” class with Cary Millsap

My first OUGN seminar on Color Magic is over. Here is a summary of what it included.
I’m truely coming back next year!

The 2nd of April: Mastering Oracle Trace Data, Cary Millsap

One day with Cary Millsap. How cool is that? I know this is the kind of words my 11 year old daughter probably would use if she could spend a day with Justin Bieber. But this day I had been looking forward to for so long. The “Master Oracle Trace Data” class with Cary in Oslo.

I’ve fallen in love with the tools from Method-R a long time ago. But after a day with Cary I realized I’ve only used less than 1 % of it. The ways you can use these tools are endless. I’ve been to several presentations with Cary before, but I always learn something new. This day was no different. And the best part – it was not over with this. The next days Cary should join us on “the boat” for the OUGN spring seminar of 2014. Well … Cary pointed out that a boat with boats on it is really a ship :-). Thanks for a great course Cary!

The 3rd of April: OUGN Day 1

This is my first time on “the boat”. I was supposed to join last year, but had to work instead. Because of this my presentation (about Oracle End-to-end metrics) was moved to the first day on shore. I have really heard a lot of great things about the OUGN spring seminar and “the boat”. Now – I finally was here.
Continue Reading »