Many topics are to be found on the web about IMPDP and UNDO_RETENTION. This one will become a more theoretical one, around the central question: Why, please why does a huge IMPDP fail with ORA-1555 if there is too less UNDO_RETENTION configured? Like so often, these questions come from a problem. I had to impdp […]
Year: 2010
Oracle Grid Infrastructure: UDEV fixing ORA-15081: failed to submit an I/O operation to a disk
If you plan to install Oracle products, be prepared for surprise of random kind. 🙂 The new Grid Infrastructure is no exception of this rule: I tried to install it on a SuSE Linux Enterprise Server (SLES) 10. Quick facts about the setup: SLES 10 SP 2 64bit Oracle Grid Infrastructure 11.2.0.1 x86_64 all devices […]
Oracle Grid Infrastructure 11gR2: How to clean up to repeat root.sh
To clean up a tilted installation of Oracle Grid Infrastructure isn’t that intuitive. I had to do it today, and this is my collection what to do and what to read. It’s made for repeating root.sh, that’s not allowed to run twice or more times without cleaning up in between. So first have a look […]
Lecture about Database Technology Basics at Augustinus Gymnasium Weiden
This year, I will talk again about basics of DB technology for 9th grade of AGW (Augustinus Gymnasium Weiden, a secondary school) again. The same event has been a success in the last years, and it’s simply nice there. Nice? Please allow me a word about this school. They have an engaged teacher, Klaus Märker, […]
Oracle: How to create a good execution plan
Sometimes you simple need to know whether a statement is fast or not, or why it is slow. (Sadly, it seems like virtually nobody wants to know why a statement is fast, but that’s another story…) Do not use EXPLAIN PLAN in such cases, it does not (can not) deal bind variables right. I’ve got […]
Oracle 11g Adaptive Cursor Sharing does not work with PL/SQL?
Recently, there was trouble in the air. I migrated a database into 11g to enjoy adaptive cursor sharing, but it did not adapt cursors. In the trouble shooting process, I discovered the following: Bug 8357294: ADAPTIVE CURSOR SHARING DOESN’T WORK FOR SQL FROM PL/SQL Nice one. A short quotation from the bug text: PL/SQL has […]
Talk about Database Technology Basics at Berufsschule Wiesau
Once again, I will talk about an IT topic at Vocational School (Berufsschule) Wiesau. This year, it’s Basics of Database Technology (Grundlagen der Datenbanktechnik) for 11th and 12th-graders, who will become certified IT specialists for software development soon. Their certification is called “Fachinformatiker der Fachrichtung Anwendungsentwicklung” in German. The paper for the talk is available […]
Oracle Technology Day Storage Optimisation – Impressions
In January, I’ve bee rather busy, so the blog was left alone. No sense in blogging just to blog. Now some content. I attended the Oracle Technology Day – Storage Optimisation in Bonn, Germany. It was a nice event, lots of information, a bit commercials, excellent catering. But this is a technical blog, let’s talk […]