For the last three days, I have been in Nuremberg, attending the DOAG Konferenz 2010 (annual conference of the german Oracle user group). This year, my list of “Look at’s” is way shorter than last years list was. It’s not the fault of the event, I just did not write down that many facts. My […]
Year: 2010
Oracle Database patch set 11.2.0.2 is out
For all who may concern 😉 Oracle 11.2.0.2 is out for Linux x86 and Linux x86_64 It’s patch set 10098816! Packaging: Starting with the first patch set for Oracle Database 11g Release 2 (11.2.0.2), Oracle Database patch sets are full installations of the Oracle Database software. In past releases, Oracle Database patch sets consisted of […]
Oracle ASM quote of the week
Please, do yourself a favour and NEVER EVER use ASM on Windows! “Dear Sir, obviously I forgot to put a file system on drives E:, F: and G: of the DB machine. I did this now, and hope you excuse the delay. Best regards John Doe Windows Server Administrator” /* no comment */ Martin […]
Oracle: Example schema for my DB lectures
This is my example schema, basis for the DB tuning lectures. Please use your “save as” function or copy the URI to use wget. expdp_klm1.dmp.bz2 expdp_klm2.dmp.bz2 Regards Martin Klier […]
Oracle 11g trace particular SQL_ID
As a follow-up of my last post, I learned that creating traces is much simpler in 11g than I expected it to be. Dion Cho and Tanel Poder pointed me to some interesting links http://oraclue.com/2009/03/24/oracle-event-sql_trace-in-11g/ http://tech.e2sn.com/oracle/troubleshooting/oradebug-doc describing how to set up a trace event on one SQL_ID without need to do it on session level […]
Oracle 11.2: Cursor Mutex S wait event and too many (2^30) child cursors
Once again, there was a lesson to be learned about the Oracle RDBMS. The occaison was a direct upgrade from Enterprise Edition 10gR2 to EE 11gR2, the application was kept untouched for good reason. Problem After running the new version for two hours, everything became incredibly slow, and the CPU load on the DB server […]
Extracting Oracle DDL from online redo logs or archived redo logs with DDLDUMP
The oracle-l mailing list made me try a new tool, created by David Litchfield. It’s called DDLDUMP V. 0.1 and extracts DDL from redo logs or archived redo logs, the output format is XML. Since it’s a windows .exe file for now, I had to use wine to test it, but it works flawlessly, and […]
Native ZFS for Linux
After long-aking FUSE implemented ZFS on Linux, Lawrence Livermore Labs have released a reimplemented ZFS for native use with a Linux Kernel. See details here: http://github.com/behlendorf/zfs Still have to test it, but I’d daresay, it was time. Good pooling Martin […]
Discovering Sybase IQ 15.1: How to add a DBSPACE on a Linux raw device?
I plan to evaluate a DBMS based on columns (not rows like Oracle, SQL Server…), called Sybase IQ these days, in order to see if we can avoid some aggregation in DSS environments. It’s a nice little niche product, quite handy, but due to its niche status, you don’t find a lot about it in […]
Oracle srvctl does not remove EONS despite it’s documented (PRKO-2013)
srvctl in Oracle Grid Infrastructure 11g Release 2 has at least one discrepancy between docs and functionality. I saw EONS consuming lots of memory in a non-database grid installation, and wanted to get rid of it. (The eONS is used by Oracle Enterprise Manager to receive notification of change in status of components managed by […]
Oracle IMPDP, ORA-1555 and UNDO_RETENTION
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 […]
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 […]