The aim of this post is to summarize the knowledge about the 12.1 and 12.2 adaptive query optimizer configuration that, as far as I know, is spread over a number of (too many) different sources.
First of all, let’s shortly review which adaptive query optimization features exist:
- Adaptive plans, which are only available in Enterprise Edition, include adaptive join methods (the ability to switch the join method from a nested
loops to a (more...)
Goal and warning
This blog will show how to invoke java code directly from within a Business Rules component. I didn’t manage to find this in the Oracle product documentation, which is actually a good thing. Invoking java code with business logic directly from within the Business Rules is normally bad design. The proper way to do it would be to first invoke business rules and then – depending on the outcome – invoke the (more...)
As many conferences evolve over the years, the number of sessions on offer can easily be overwhelming. I have overheard many conference attendees wrestling with their choices for what to see and which sessions to attend.
For DOAG 2016 I have a short overview with my picks and with one or two tip-sessions. I hope this helps, though it is just my personal preference of course…
Please note that this post is based on the (more...)
Just a stupid error. Posting it so that someone else googling for the same thing can get a clue.
An ASM instance running with default parameters (no pfile, no spfile). Updated spfile for the instance with asmcmd spset command and bounced crs. After reboot also, it still wasn’t using spfile. Got puzzled and checked GPnP settings again. All looked good. Then in alert log came across this
ERROR: SPFile in diskgroup <> does not match (more...)
This note comes to you prompted by “Noons” in a recent twitter exchange
In response to a complaint by Lukas Eder about having to educate people in 2016 that there is no (performance) difference between count(*) and count(1), Nuno asked me to blog about my claim that this non-difference is a good educational example on at least three different counts.
One thing I won’t count in the list of three is an actual demonstration (more...)
I was googling for things related to NOLOGGING operations and found this useful post on the Ask Tom web site: url
There is a nice table in the post that shows when insert operations generate redo log activity. But it isn’t formatted very well so I thought I would format the table here so it lines up better.
Table Mode Insert Mode ArchiveLog mode result
----------- ------------- ----------------- -----------
LOGGING APPEND ARCHIVE LOG redo generated
I received this error message when I was playing around with Extended Policy Framework in Oracle Clusterware 12c.
Policy-managed environment in Oracle clusterware 12c offers the capability to create policies to configure pools in accordance with business needs or application demand, so that pools provide the right service at the right time. Typically, administrators create multiple policies to reflect differences in requirements for the cluster based on business needs or demand, or based on (more...)
I am working on a production issue. I do not think that we have a database issue but I am graphing some performance metrics to make sure. I made a new graph in my PythonDBAGraphs program.
It shows the average number of active sessions for a given minute. It prompts you for start and stop date and time. It works best with a relatively small interval or the graph gets too busy. Red is sessions active (more...)
(Disclamer: any opinions expressed here are fully my own and not representative of my employer)
photo by alvaroprieto (cc 2.0)
Super excited to be working at Amazon on my passion which is performance data visualization and database monitoring. Suffice it to say this is the most excited I’ve been about work in my career and I’ve had ample opportunity to work on database performance in the past such as at (more...)
Just a short post to announce that I’ll be presenting an User Group Forum session. Thanks ODTUG!
SQLcl: A Modern Command Line Interface to the Oracle Database [UGF5641]
“In this session learn about the new Java-based command line interface that takes advantage of Oracle SQL Developer’s scripting engine. It delivers a modern command line interface that is backward compatible with SQL*Plus but also introduces new commands and features that have been missing for a long (more...)
In Oracle 11G, DG Broker needed to be told whether the standby database was physical or logical. The command to add database in 11G was something like this:
ADD DATABASE <DB Unique Name> AS CONNECT IDENTIFIER is <TNS Descriptor>
MAINTAINED AS [PHYSICAL|LOGICAL];
Oracle 12c is definitely smarter and can figure it out on its own. The “ADD DATABASE” syntax is simpler:
DGMGRL for 64-bit Windows: Version 18.104.22.168.0 – 64bit Production
Synthetic full backup is a method for combining incremental backup into a full backup. It is not a new thing, many backup utilities can do that with file system backups. It is also well described:
However, there is only one backup suite that can do that with Oracle RDBMS: Commvault 11.
How is it done? Well, Commvault is a very well documented tool, the documentation is here:
Having take a new job at Amazon just two weeks ago and moving to Seattle (!) I didn’t have the time nor was it practical to set up Oaktable World this year. Luckily Kelly Pot’vin has taken over the mantel !
Get the info straight from the horses mouth at her blog.
The following content has been graciously supplied from Kellyn’s blog:
Oak Table World is FREE to the PUBLIC! We don’t require an (more...)
Tuesday, September 20, 2016
5:00 PM to 7:00 PM
138 Minna Street, San Francisco, CA (map)
Oracle OpenWorld is a time for us to join together and learn all about what Oracle has to offer. But let’s get real, it’s always nice to get free beer. To help show us a good time here in San Francisco, our good friends in the Oracle ADF and Database developer group are planning a Oracle Developers (more...)
It’s frustrating to have to spend time jumping off into web security and wordpress configurations when there are so many other things that are important to be doing. Today the DoS continued and the Jetpack solution didn’t seem to work. The other two solutions from Digital Ocean didn’t seem reasonable. One was to re-install wordpress with there install version. Nice that they offer a better security protected version but I didn’t feel like re-installing my (more...)
This site had been running for a years with no big issues.
I had performance and system saturation issues about 3 years ago and then move the site to DigitalOcean.com.
They are inexpensive and the performance is awesome.
Then last Monday and every day since the site had been going down.
Simplest “solution” for me was just to get on and bounce the machine.
That cleared it up.
After this went on for a (more...)
Session ID: UGF3110
Advanced Active Session History Analytics
09/18/16, 03:30:00 PM – 04:15:00 PM
A coworker passed a test script on to me that was failing with the following memory error:
ORA-04030: out of process memory when trying to allocate 4088 bytes (PLS CGA hp,pdzgM64_New_Link)
The error occurred when initializing a PL/SQL table variable with 7500 objects. Here is my sanitized version of the code:
CREATE OR REPLACE TYPE ARRAY_ELEMENT
n4 NUMBER );
CREATE OR REPLACE TYPE MY_ARRAY
set last_posting_date = date'2016-08-18';
It’s been a while since I’ve published here. You see, I’ve been kind of busy.
Back in January 2015 I was lucky enough to join Oracle as part of their Developer Advocate team. My focus is SQL.
You see I love working with SQL. And I love helping others. So joining the Developer Advocates was a great chance to combine these passions :)
Which leads some to ask:
Why is your site (more...)