Posts Categorized: Technical Blog
As a follow up from my previous post on Exadata Design, where I question the use of dimensions for certain attributes in data warehouses, I figured I should test whether HCC works with tables that have more than 255 columns, It does. Here’s my test case.
Michigan OakTable Symposium (MOTS) is a unique event taking place just before Oracle OpenWorld — 16-17 September. Why unique? This is the first conference (is it not?) where all presenters are members of OakTable Network, a group that gathers number of like-minded IT professionals with scientific approach to Oracle database technology and to the life in general.
As of this afternoon, version 22.214.171.124.1 of Oracle’s Exadata storage server software, is out in the wild. This is the first publicly available version of the 126.96.36.199 branch, a major release including a full OS image with an update to Oracle Enterprise Linux 5.5. A number of bugs causing cell server crashes and hangs have been fixed, including 9472035, 9870117, and 9722560.
Hello, and welcome to Log Buffer, a weekly blog about happenings in the database industry. Today is a celebration of the 200th edition of Log Buffer, and we’d like to give a special shout out to all of our guests hosts over the past 4 plus years. Their contributions have been invaluable in helping to grow Log Buffer into the community source of favorite database-related blog posts that it is today.
Welcome to Log Buffer. The weekly review of DBA industry news. Enjoy Log Buffer #199.
Oracle Exadata V2 is a very well balanced database machine combined with smart and innovative software. One of these innovative features is the Storage Index – a game changing feature in my opinion.As with any feature, there are intended use cases, limitations and caveats. Use it right, and amazing performance gains can be achieved. Use it wrong, and nothing will happen. This is what is great about storage indexes in particular. They are there, without any overhead. It’s only a question of how to leverage them, in addition or combination withevery other feature that Oracle Exadata has to offer.
I’m not aware of any TPC results for Exadata V2. However a TPC-C test was run in late 2009 using a Sun F5100 flash array on Sun T5540 servers, setting a record for the benchmark that still stands. The Oracle wiki has a great overview of the various benchmarks and what they actually measure.
We’re in the process of applying Exadata Bundle Patch 5, and ran into an issue I wanted to share.The system didn’t have a XDB user, and likely because of this, the two “alter package” commands invalidated the dbms_metadata objects. The subsequent recompilations all failed. On advice from Oracle support, we ended up backing out the patch and re-applying without running these “alter package” commands, and confirmed that DBMS_METADATA works fine. So if you don’t have XDB installed, skip the “alter package” commands. I hope the README is updated soon.
My article Making the Most of Oracle Exadata in the August 2010 issue of the NoCOUG Journal has come out. It covers Exadata’s feature set, and then dives deeper, discussing how to make the best use of its capabilities. For those of you not subscribers of the print edition, it’s also available electronically.
We settled down to some very interesting talks, the highlight for me being Tim Bunce’s talk on using Devel::NYTProf to Optimize your code. The rest of the day was dedicated in my opinion, to the future of DBs in with Nelson Ferraz giving an excellent presentation of his concepts for using Perl as to glue for a Data Warehouse application. Next on my agenda, Martin Berends reports on the present state of Perl 6 and interfaces database. Martin was quickly followed by Tim Bunce again who presented his proposal for the new Perl 6’s DBDI.