I have not had a lot of time to post recently due to various reasons and a switch in jobs at Oracle. I currently am 100% dedicated to working in the Oracle Solution Center to help customers test the performance on Oracle’s engineered solutions. So, why am I sending this link?
Regardless of the performance tests that are performed, I often spend a fair amount of time showing the Availability aspects as well. Hopefully this video will help to demystify the availability aspects of Exadata.
Article #3 in my ongoing series covering SQL statistic functions in Oracle Database is now up. The topic is the median:
MEDIAN: For When You Don't Really Mean It
Median is useful in typifying a data set when the data might be skewed, or in the presence of extreme outliers. For example, the U.S. Census Bureau reports median household income for states and counties so as paint a picture unskewed by the presence of, say, Bill Gates or Warren Buffet living just down the street. To learn more, hit the link.
I got an email a few days ago . . .
Subject: Exadata / your blogs / you aren’t saying to put HINTS on everything, Are you…
. . . A peer of mine found a couple of your blogs listed below which discuss Profiles and Hints. The position he is inferring upon you is that you are stating unequivocally that we should create lots of indexes, add hints, create profiles and outlines on our Exadata machine. Having read your book and achieve actual results in line with that book, I know that pretty much the opposite is true. . . .
Here’s what I said in my reply (edited a bit to clean up typos and to be a bit more precise):
You’ve probably seen questions on the internet occasionally about finding out how frequently an object has been modified. The question is a little ambiguous – does it mean how much change has occurred, or how many DML statements have been executed; either may be an interesting measure. Of course, Oracle gave us a method of answering the first question a long time ago: v$segstat (or v$segment_statistics if you don’t mind doing the join) and the resulting content in the AWR or Statspack reports:
With Exadata version 126.96.36.199.0 came the Unbreakable Linux Kernel for Exadata, which had been the stock EL5 redhat kernel prior to this version (2.6.18). With the unbreakable kernel came the opportunity to run the perf utility. This utility has the opportunity to see which functions are active inside an executable when there’s a symbol table. And the oracle database executable has a symbol table! One reason to do this, is to get a more granular overview of what the Oracle database is doing than the wait interface, especially to get a more detailed overview of what the database is doing in what is visible in the wait interface as ‘on cpu’.
Did you ever miss the older listener log file format and want to turn off the ADR-style log introduced in 11g? Well, it's really very simple.
Oracle introduced the Automatic Diagnostic Repository (ADR) with Oracle 11g Release 1. This introduced some type of streamlining of various log and trace files generated by different Oracle components such as the database, listener, ASM, etc. this is why you didn't find the alert log in the usual location specified by the familiar
background_dump_dest initialization parameter but in a directory specified by a diferent parameter -
ADR_BASE. Similarly listener logs now go in this format:
At last week’s Dallas Oracle Users Group meeting, an Oracle DBA asked me, “With all the new database alternatives out there today, like all these open source NoSQL databases, would you recommend for us to learn some of those?”
I told him I had a theory about how these got so popular and that I wanted to share that before I answered his question.
My theory is this. Developers perceive Oracle as being too costly, time-consuming, and complex:
Recently I’ve spoken at the RMOUG training days 2013 in Denver (the mile high city). It was a first time for me to speak for the RMOUG and being in Denver. Thanks to the “sequestration” (federal budget cuts) the lines piled at immigration at Minneapolis (Minneapolis and Saint Paul, the twin cities) airport, and because my plane left more than one hour to late and my layover time was one hour and fifteen minutes, I tried to rebook my flight from Minneapolis to Denver. But, this flight turned out to be delayed too. This meant I was able to get on this flight!
Followers of the blog know I’m an Oracle database guy, but my current job also has me honing my newbie WebLogic 11g skills, setting up a number of servers to deliver ADF and Forms & Reports 11gR2 applications.
As you’ve no doubt heard, Oracle have just released the 188.8.131.52.0 version of JDeveloper and ADF. I tried applying the 184.108.40.206.0 patch to a WebLogic 11g (10.3.6) installation and it worked without any problems (see here).
Hierbij nog dank voor allen die aanwezig waren bij de weer gevulde, informatieve & gezellige avond tijdens “Hotsos Revisited 2013″. Wij presentatoren hebben genoten van het ambiance. Hier ook nog voor degenen die graag het nog een keer willen nalezen het presentatie materiaal van Toon, Jacco, Gerwin, Frits en mij… Presentatie materiaal in alfabetische volgorde: …