The summer is flying by and in no time it will be October and that means Oracle OpenWorld 2011 should be on your radar. Once again the Oracle Real-World Performance Group will be hosting three sessions. For those unfamiliar with our presentations, you will get marketing free, no nonsense performance insight of the highest caliber from...
Troubleshooting Oracle Exadata
The crew at My Oracle Support (MOS) have an excellent starting point for troubleshooting Oracle Exadata. I’d recommend to add this one to your MOS bookmarks. Oracle Database Machine and Exadata Storage Server Information Center
Data Science Fun with the OOW Mix Session Voting Data
Over the past few weeks Oracle Mix had opened the Oracle OpenWorld 2011 Suggest-a-Session to the general public where anyone could submit or vote on a session. One limitation of the Oracle Mix site was that it was impossible to sort the sessions by votes but that challenge was tackled by Roel Hartman with...
Real-World Performance Videos on YouTube – OLTP
In addition, here are some OLTP demos that demonstrate how much performance and throughput can be wasted by poor design and suboptimal database programming. OLTP Performance – The Trouble with Parsing OLTP Performance – Concurrent Mid-Tier Connections
Real-World Performance Videos on YouTube – Data Warehousing
Here are some videos of a data warehouse demo that the Real-World Performance Group has been running for a while now and we thought it was time to put them on YouTube. Hope you find them informative. Migrate a 1TB Data warehouse in 20 Minutes (Part 1) Migrate a 1TB Data warehouse in 20...
Implicit Datatype Conversion + Histograms = Bad Execution Plan?
Earlier today I exchanged some tweets with @martinberx about some optimizer questions and after posting more information on the ORACLE-L list, I was able to reproduce what he was observing. The issue: DB: 11.2.0.2.0 – 64bit I have a small query with a little error, which causes big troubles. The relevant part of the...
Philosophy – Measurement
In my professional opinion, if your performance work is to have any credibility then you need to agree with and abide by this philosophy. I think it’s really what separates the real experts from the amateurs. “Measurement is the first step that leads to control and eventually to improvement. If you can’t measure something,...
NoCOUG Interview
Since I’ve been on a blogging hiatus for the past few months (and hopefully that will change shortly) I thought I’d mention that the inverview I did with the famous Gwen (Chen) Shapira has now been published in the May 2011 NoCOUG Journal. Hopefully you find it interesting and insightful. Feel free to leave...
Debunking More Netezza FUD About Exadata
A reader recently left a comment for which my reply was longer than I’d like to leave for a comment so I’m answering it in detail with this blog post. Gabramel writes: Greg, Nice article. I am just reading the Netezza paper. You don’t appear to have debunked the following statement. “Exadata is unable...
Making the Most of Oracle Exadata – A Technical Review
Over the past few weeks several people have asked me about an Exadata article entitled “Making the Most of Oracle Exadata” by Marc Fielding of Pythian. Overall it’s an informative article and touches on many of the key points of Exadata, however, even though I read (skimmed is a much better word) and briefly...
EMC Greenplum Data Computing Appliance Real World Benchmarks
Today EMC Greenplum (I guess that is the “official” name since the acquisition) launched their new product offering and as part of that announcement they published some performance numbers around data loading rates. Let’s examine what’s behind this loading rate number. Real-World Benchmarks Benchmarks and benchmark results are often criticized (and sometimes rightfully so) because they often...
Reading Parallel Execution Plans With Bloom Pruning And Composite Partitioning
You’ve probably heard sayings like “sometimes things aren’t always what they seem” and “people lie”. Well, sometimes execution plans lie. It’s not really by intent, but it is sometimes difficult (or impossible) to represent everything in a query execution tree in nice tabular format like dbms_xplan gives. One of the optimizations that was introduced...