A TNS error at night…
Sometime ago my data warehouse colleague came to me with a TNS error. At night times he runs his batch jobs in order to update his data warehouse. That night one of his jobs did not run properly and generated an ORA-12592 error. He had to restart this job during daytime.
It turned out it was not the only occurrence of this TNS error. A couple of days later he (more...)
A couple of people have asked me recently about a classic problem that most DBAs know: how to view ASM trace files in the VIM editor when the filenames start with a + character. To my surprise, there are actually quite a few different ways of doing it. Since it’s come up, I thought I’d list a few of them here… If you have another one to add, feel free to comment. I know that (more...)
OTech Magazine – Summer 2014
The fourth issue of OTech Magazine, the independent magazine for Oracle professionals, is available. For the summer 2014 issue there are some more personal articles included. Titles vary from The Spiritual Programmer to The Next Generation: Oracle SOA Suite 12c and back via How to protect your sensitive data using Oracle Data Vault.
Download OTech Magazine – Summer 2014 here.
Have you ever wondered why it takes a century to completely refresh your materialized view? I did, so I did some testing.
Recently I was asked to support a customer whose database was extremely slow. As it turned out, some indexes had been created on a materialized view and that view was being refreshed. Soon I found that a large ‘delete from’ job was running, which turned out to be part of the complete refresh.
In August 2014 Oracle released its RDBM 22.214.171.124 with a potentially useful and exiting new option: Database InMemory. Upon reading about it it became clear to me that this is a powerful option, worth examining deeper.
This blog will briefly describe what InMemory is and what it isn’t. The emphasis however is on practical examples. I didn’t have a real database at hand for some ultimate real life experience, but a local (more...)
About 2 months ago I wrote an article about setting up user authentication in Cloud control, based on their account in the Active Directory. As promised, here is the second part describing Cloud Control authorization with Active Directory.
A small recap about why this could be useful:
If your company is preferring Microsoft Active Directory (further named AD) as a source of truth (or at least you´re trying to) you should be using the AD (more...)
In my previous post on the subject of the new ASM Filter Driver (AFD) feature introduced in Oracle’s 126.96.36.199 patchset, I installed the AFD to see how it fulfilled its promise that it “filters out all non-Oracle I/Os which could cause accidental overwrites“. However, because I was ten minutes away from my summer vacation at the point of finishing that post, I didn’t actually get round to writing about what (more...)
Half a year ago, my colleague Remco wrote an article on auto starting the listener and the databases after a host reboot. As usual with Oracle, there are several solutions. In a previous job, I learned to appreciate Oracle Grid infrastructure to do the same. And then some more.
Oracle Grid Infrastructure can be downloaded and used for free. It serves many purposes, especially for ASM and RAC,but as it turns out, it can be (more...)
This is a very quick post, because I’m about to log off and take an extended summer holiday (or vacation as my crazy American friends call it… but then they call football “soccer” too). Before I go, I wanted to document my initial findings with the new ASM Filter Driver feature introduced in this week’s 12.1.o.2 patchset.
Currently a Linux-only feature, the ASM Filter Driver (or AFD) is a replacement for ASMLib (more...)
This is a post about Oracle Automatic Workload Repository (AWR) Reports. If you are an Oracle professional you doubtless know what these are – and if you have to perform any sort of performance tuning as part of your day job it’s likely you spend a lot of time immersed in them. Goodness knows I do – a few weeks ago I had to analyse 2,304 of them in one (long) day. But for anyone (more...)
For some time now I have preferred Oracle SLOB as my tool for generating I/O workloads using Oracle databases. I’ve previously blogged some information on how to use SLOB for PIO testing, as well as shared some scripts for running tests and extracting results. I’ve now added a whole new landing page for SLOB and a complete guide to running sustained throughput testing.
Why would you want to run sustained throughput tests? Well, one (more...)
I wrote about the Code Based Access Control (CBAC) stuff in Oracle Database 12c a while back.
I’ve recently “completed the set” by looking at the INHERIT PRIVILEGES and BEQUEATH CURRENT_USER stuff for PL/SQL code and views respectively.
Moving datafiles has always been a pain. There are several steps, it’s fairly easy to make a mistake and it requires the datafile to be offline. There are also different steps depending on whether the database is in ARCHIVELOG mode or not. In ARCHIVELOG mode, the steps are…
1) Take the tablespace containing the datafile offline
2) Copy/rename the datafile at the OS layer
Use ALTER TABLESPACE…RENAME DATAFILE (more...)
!The code contained in this post is meant to be used at your own risk!
With any Oracle GoldenGate replication configuration, it is always good to monitor what is going on. One aspect that many people want to know is how can I validate that every record is being transferred to the target system. Once such way is to use Oracle Veridata; however, some times there is not enough time to setup and (more...)
In the past I have been a little critical of Oracle’s support notes and documentation regarding the use of Advanced Format 4k storage devices. I must now take that back, as my new friends in Oracle ASM Development and Product Management very kindly offered to let me write a new support note, which they have just published on My Oracle Support. It’s only supposed to be high level, but it does confirm that the _DISK_SECTOR_SIZE_OVERRIDE (more...)