Category Archives: Performance

Batch: Using partitions and “deleting” local indexes for fast DML

Recently I was presented a batch job with unacceptable running times. Especially the first stage of loading and normalizing data, just took to long time. When doing trace I found that about 70 percent of the time was spent doing inserts and updates towards to tables. For both of these, Oracle was reading way more […]

Oracle and Hibernate: Not always best friends

I’m definitely not a Java or Hibernate expert. But I have worked with Oracle for the last 15 years since version 7.3.4. I’ve also spend the last 10 years focusing and working mainly with performance issues within Oracle databases or within the code accessing Oracle databases. Lately many of the projects I’ve been working on […]

After upgrading from Oracle 9i to 11g

Saturday we upgraded one of our Oracle databases in production from version 9 to 11g Release 2. Yes – you heard right! From Oracle 9i … Well it’s a long story, and I’ll leave that for now. What I do want to blog about is some of the changes in Oracle 11g. I’ve used Oracle […]

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 […]


In Oracle 9i the DBMS_XPLAN package was introduced. One of the most used functions in this package has been the DISPLAY function. From version 10g this package was extended to include two other related functions: the DISPLAY_CURSOR and the DISPLAY_AWR functions. In this note I´ll take a look at the function first introduced in 9i […]

Oracle Statistics: A summery

In this blog I want to collect my notes regarding the different Oracle statistics. This will definetly not be a complete overview, but only a summary of my findings and readings about more or less useful parameters that I stumble a cross. If you have experiences or knowledge that should be added, please post a […]

Useful articles regarding statistics on partitions

One of the blogs that I´ve been following is Doug’s Oracle Blog. Doug has for instance written a series of articles regarding statistics on partitions. This series is definetly worth reading, and you can find the first article here:

JavaZone 2011

This was my first year on JavaZone, and I was very excited about this conference. And I definetly did not get disappointed. My work is mainly about Oracle, but I work together with a lot of Java developers and have many common challanges. I´m planning to write more javacode myself, but recently I mainly do […]