Author: Mathias


Speaking at Orcan Conference May 11-13

TweetShareSharePin0 SharesJust a quick note that I have accepted to speak at the conference the Swedish Oracle User Group Orcan will hold May 11-13. The subject will be on rowid, ITL, and row migration where I hope to show it both from the block level view and a little showing it from the OWI view. THe general idea is to show more on what happens in the blocks and why and how the rowid a row first gets when it […]


Pro Oracle Application Express Sample Spreadsheet

TweetShareSharePin0 SharesThe excellent book Pro Oracle Application Express book by John Scott builds an application through the book and it starts with a sample spreadsheet showing a set of reported bugs. I was not able to find a downloadable version of this so I created it. Not much work and very easy to do, but also not very enjoyable. Since I created it with google docs it is easy to share it, so I figured I’d post a link here […]


Time to resurrect this blog

TweetShareSharePin0 SharesOK. This blog has been dormant for longer than what should have been possible. Having moved across the world, started a new job, and returned career focus to Oracle specialist (from more or less forced management roles) it’s definitely time to start writing again. The first step has been to move it to a proper blog platform, it is now at and the same feed as before ( Assuming this works and it gets to the blog reader, next post […]

New Stuff

Oracle 11g Launch

TweetShareSharePin0 SharesOracle’s launch of database 11g will be webcasted. It starts at 10 AM ET. Unfortunately I’ll probably miss the live webcast as we’re wrapping up visits and packing today to fly out early tomorrow to return back to Colorado. I’m sure the coming week will be filled with blogs and articles about all the exciting things in 11g and with the things we’re disappointed to not get in this version. TweetShareSharePin0 Shares

SQL, Oracle

Supported version of skip locked?

TweetShareSharePin0 SharesAs Pawel showed in his post some details about how the row scn technology works in specific situations isn’t as well documented as you’d wish. I asked Oracle development to clarify the questions I had and the answer back was both interesting and useful. Every kind of update and lock on a row will make the rowscn for the row/block NULL until the updating/locking transaction completes. That is, any kind of lock and update can be identified when retrieving […]

Partitioning, Oracle, Licensing, DBA

Rant about partitioning licensing

TweetShareSharePin0 SharesI’ll give myself a quota for no more than one rant a month. However, one of my pet peeves is how Oracle licenses the database. I’l probably return to why I dislike the general model in a future rant, but this on e will be specific to partitioning. To use partitioning, you have to pay for the Enterprise Edition of the database at $40,000 per CPU and then pay an additional $10,000 for the partitioning option. That is a […]


Optimistic Locking with ORA_ROWSCN

TweetShareSharePin0 SharesAre you using 9i/10G and still implement optimistic locking with your own column rather than through Oracle’s pseudo column? So am I, but I couldn’t really explain why. My main (defensive) argument would be that the system was built long before 9i. Still, it would make sense for us to change it. Let’s look at a, hopefully, quick example. Let’s first create a user with two tables and add the same data to both tables. Two tables with just […]

Oracle, Blogging

Who reads blogs

TweetShareSharePin0 SharesReading this post about why the average Oracle IT worker doesn’t read blogs got me thinking. Does the average IT worker read blogs? I’m not sure. In what I have observed, it is something a segment does. I’d contend that the average blog reader is more advanced and more thirsty for more knowledge that the average person in the same field. I think it is also something the more internet aware do. Everyone knows about the internet, but how […]

XML, SQL, Oracle, Challenge

SQL Challenge I – Solution

TweetShareSharePin0 SharesBoth Gary and Philip postd working versions. Gary’s didn’t work for me when I had the same letter more than one time in the string. Philips did work and the need to deal with each letter as if it is unique can of course be questioned. The intent was for a solution that could handle that and as Philip showed adjusting that is as easy as to just add a distinct. My version is based on not using analytical […]


SQL Challenge I

TweetShareSharePin0 SharesWhile maybe a pretentious title, I’ve always enjoyed getting and giving what I call SQL Challenges. It is basically a short explanation for what you should do with pure SQL and some limitations to how you can do it and then you get to try to come up with a solution. It is frequently more about being able to do it, than it is that one would actually implement it that way. The idea is that you lear new […]