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  • Explain plan doesn’t peek at variables

    I was trying to experiment with the 11g SQL Plan Management feature when stumbing across this. You will most likely go “ohh-of course it doesn’t” but I didn’t know it for sure until now. It’s another reason the expected explain plan differs from the actual explain plan, as discussed on the oracle-l mailing list recently.…

  • UKOUG Conference-session review part 3

    The final installment of this series deals with Tom Kyte’s top 10 features in 11.2 and Wolfgang Breitling’s “seeding statistics”. Tom Kyte – Top 10 new 11.2 features 1) dbms_parallel_execution: I was a little late so didn’t get the essence of this. Seems to automatically do what Tom described as “poor man’s parallelism” in his…

  • Let there be multipathing (when there wasn’t before)

    One of the projects I was working on recently couldn’t be finished as it should have been due to a lack of switch ports in the SAN. The QA database servers therefore only had single pathing to the storage whereas the production kit (thank god!) had multipathing enabled and configured correctly. UPDATE 221219: this document…

  • UKOUG conference 2009-session review part 2

    This is the second part of my review of UKOUG conference 2009, day 1. Check out the first part as well! This picks up exactly where I left part 1 after Tom Kyte’s session. Virtual Insanity I remained in hall 1 to see the great presentation of James Morle. I have to say that even…

  • Do not shut down ASM when dropping a disk

    I was doing some maintenance today with an ASM disk group (10.2.0.4.1 64bit on RHEL 5.3). UPDATE 221219: this post refers to software that has long gone out of support, the information therefore has been archived and should no longer be referred to. In a nutshell, we swapped disks in the FRA to increase the…

  • A day at UKOUG Conference in Birmingham

    What a great decision to go to UKOUG #tech_ebs on Monday! I’ve managed to see presentations from Wolfgang Breitling, James Morle and Tom Kyte (twice). So that was good. But the even better part was catching up with Julian Dyke, Piet de Visser (I promise I will read more of your blog!), David Kurtz, the…

  • Selectively purging the shared pool

    Another very useful thread has developed on the oracle-l mailing list. On a side note, this is really _the_ list to be subscribed to-there are so many experienced Oracle DBAs out that it’s pure joy. But I digress, back to the problem I often face when performance troubleshooting systems is to purge a SQL statement…

  • Oracle’s secure external password store

    This post has been published in 2009 and a lot has happened since that day. It appears as if it was still quite popular, which is why I decided to update it to Oracle 19c. What hasn’t changed though is the lack of adoption of this feature. I can’t quite understand why there are still…

  • ORA-02290: check constraint (RMAN.AL_C_STATUS) violated

    I ran into this problem today when I was working on a backup problem. The scenario is as follows: Oracle 10.2.0.4 EE RHEL 5.2 PAE kernel, i.e. 32bit Backup taken on the standby database Using a recovery catalog UPDATE 221219: both Oracle 10.2 and Red Hat Enterprise Linux 5 have long since reached their designated…

  • Getting started with iSCSI part IV-Slightly advanced material

    The final part of the article series focuses on some slightly more advanced topics, such as deleting targets, device name stability and insight into how the automatic login works. UPDATE 221219: this article was written for Red Hat 5, which has since reached its designated End Of Live. The article is archived and should not…