Side effect of ExaWatcher workaround for LSOF check
While analysing the problem with ExaWatcher not being able to start, I found quite nasty side effect of a workaround implemented in recent versions of this useful tool. In fact, you will hit it only on Exadata X7 where you had previously implemented another workaround…
Design Tips for Query Rewrite
Although Query Rewrite on Materialized Views is a powerful feature which is available in Oracle databases for a long time, it is rarely used. Many developers and database administrators don’t know about it or do not use it because they think it is too complex….
Learn and certify for free: Oracle Cloud Infrastructure and Oracle Autonomous Database
If you ever hesitated to jump into learning about Oracle Cloud Infrastructure or Oracle Autonomous Database the time is now! Oracle Cloud Free Tier together with Always Free Services is already available since last year. This is very useful, as it allows to familiarize with…
Useful Oracle tools – purgeLogs
Recently I’ve came across a nice tool provided by Oracle named purgeLogs, so I would like to shortly blog about it for reference (also for me). As the name suggests it is meant to be used for cleaning up log and trace files. Unfortunately, it…
Data Vault Queries and Join Elimination
If you work with Data Vault for a data warehouse running in an Oracle database, I strongly recommend to use Oracle 12.2 or higher. Why that? Since Oracle 12c Release 2, join elimination works for more than one join column. This is essential for queries…
Moving to GitHub
Over the years, my blog has become one big mess. It was no longer a blog. It contained product pages, change logs, software downloads, FAQs and even a forum. That was a nice experiment. But now it’s time to move everything that doesn’t belong in…
Update Center for Free SQL Developer Extensions
Introduction In July 2017 Oracle announced to release updates for SQL Developer on a quarterly basis. Installing multiple versions of SQL Developer on the same machine is not a problem. Therefore many developers install a new version as soon as it becomes available. On the…
Small fix for SQLcl Java problem with Oracle 12.1
Let’s say you want to quickly use some cool features of SQLcl inside the script running on the database server, but only Oracle below version 12.2 is available there (which is the first one being shipped with SQLcl). This means that you have to download…
Constants vs. Parameterless Functions
Do you use parameterless PL/SQL functions in your queries? Did you know that this may cause performance issues? In this blog post I explain why parameterless functions can be the reason for bad execution plans in any Oracle Database. I recently had to analyze this…
Conference Review 2019 (Part 3)
In the last four weeks, I had the chance to speak at three different conferences. This was the finish of an intensive conference year for me with many impressions, learning, knowledge sharing, new and old contacts and of course a lot of fun. I am…
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