Friday was the first search episode of DB2’s Got Talent on the DB2Night show. I was thrilled to have an opportunity to step in as a guest judge for Klaas, who was traveling and unable to participate. It was really neat to be on the other side of the competition. I very much enjoyed the lack of the nervous feeling I always had when I was a contestant. It is really hard to be judged so directly.
Two of the scheduled contestants were unable to join or had technical issues. Luckily the slate of contestants we were left with were excellent. Overall, I was impressed that everyone came in on time, and had readable slides.
Robert Goethel Presented on CPU Speed.
Robert spoke clearly. I noticed that he did not have a presentation title, other than “DB2’s Got Talent 2014”. There was an element of extra suspense as he went through his first slide or two. I still think I prefer a descriptive presentation title.
His topic was interesting. CPUSPEED is a DBM configuration parameter that is the number of milliseconds per instruction. DB2 sets it automatically when you first install/configure, but it is only updated after that when an upgrade is done. One of the best things about this is that DB2 will re-calculate the value for you if you simply set the parameter to -1. Robert advocated updating it more frequently, particularly in some of today’s VM-heavy environments. CPUSPEED very highly impacts the access plans that DB2 chooses, so it is critical to good performance.
Robert did a great job. I would like to see the actual screen shot or at least what it looks like syntactically when one updates CPUSPEED. I also think that with a bit more time, he could have reduced the wordiness on his slides. The slides did a great job of telling the whole story, but personally, I prefer to tell the story myself and just have highlights on the slides. I liked his use of graphics on slides.
Saurabh Agrawal Presented on Database Purging
This is a topic that is near and dear to my heart. I advocate pruning or archiving of data from e-commerce databases where it just gums up the database and slows performance. Saurabh presented about one of my favorite methods for deleting data when it gets really out of hand. His slides were laid out nearly perfectly – much like I would have laid them out. They may have been a bit light on graphics, but that’s no major issue.
He covered the problem he was trying to solve (deleting large amounts of data), approaches that are well known and that he considered (foreign keys with cascading deletes, stored procedures that can control commit counts), and then went into his chosen approach in detail (exporting data to keep, clearing table,
LOADing data back into the table).
It sounded like he was using this process in a data warehousing environment, so I’d guess that is why he did not mention that the method described requires the table in question to be inaccessible while the process is going on. Lack of mentioning that is my only real criticism of his presentation.
Saurabh made me realize that I haven’t blogged on this topic/method very extensively, so I’ll be looking for an opportunity to do so.
Mariana Sanches Presented on Automation
Mariana used a innovative tool – Prezi – for her presentation. It was really refreshing to see something that wasn’t just slides – not that it was vastly different, just it was a nice touch.
Mariana chose an overview of a larger topic, so didn’t have much time for some of the details, but I liked the topic. It was highly technical and really made me think that I should look into automated maintenance again. I was not aware of the use of an XML file that can configure details about reorgs. Though I’m still not sure I’m ready to relinquish control of runstats.
One of the amazing things to me about DB2’s Got Talent is that I learn something every single episode I watch. Today was no exception, and I continue to come away inspired with new ideas for blogs and new ideas of things to work on.
I have included contact information supplied by the contestants above, but have not gone as far as including email addresses. If anyone wants additional contact information included, just leave me a comment below, and I’ll add it.