Category Archives: DBA

11gR2: “Unlucky” combination of a new feature, a fix, application design and code

Sometimes a new feature (and/or a fix) could give some very unexpected results. In this article I’ll show how a mix between a 11g new feature (Adaptive Cursor Sharing), a fix (in 11.2, the obsolete threshold), application design (a separate schema for every customer), and code issues (not prefixing objects with schemaname, and bind datatype […]

New feature 11g: DBMS_SQLDIAG to dump 10053 trace

Almost everyday I learn a new 11g feature. Today I found this way to dump a 10053 trace for a existing cursor. I wanted to get a 10053 trace on a query already in library cache. I did not want to flush shared pool. I was thinking about gathering statistics with NO_INVALIDATE=false. But this was […]

End To End Metrics: A bridge between the developer and the DBA

First time I heard about end-to-end metrics was in a presentation given by Cary Millsap. The name of the presentation was “Thinking Clearly About Performance”. The presentation was great. One of the quotes that I really enjoyed was “Performance does not happen by accident! It’s a feature.”. One of the main topics in the presentation […]

Article: Faster Batch Processing and Logging by Mark rittman

I just read this article about efficient error handling when running batch jobs. This is somethink many DBAs and developers should put on their mind, and consider using next time they’re planning to do dataloads or batch jobs.

Running Toad under wine in Ubuntu linux

Finally I got a description on how to run Toad for Oracle under wine in linux. The description is not quite “out-of-the-box”, but with a little fiddeling around I got it to work: I had to remove wine, and install the 1.4 version (just upgrading from 1.3 to 1.4 did not work). Then I […]

So many DBAs; yet so many performance problems

There are many applications and databases around, performing and scaling just as supposed to. We very seldom hear about these project. Of course, this could be small applications with small loads; or, on the other hand, this could be well design application with well written code, and well maintained databases. Yet there are so many […]

Flashback Session … that was cool! Thanks mate!

Today my ass was saved by my good friend and colleague, Lars Johan Ulveseth. Thanks mate! Yes I messed up … just a little … in a test environment. But it could have made a lot of mess.

When to rebuild an Oracle index?

For several years now it’s has been clear that we shouldn’t just rebuild an index. In the worst case this could make performance even worse than it used to be (for the next following days). So the question is “What indexes should be rebuilt?”. I just read this article from Jonathan Lewis that might just […]