Search

Top 60 Oracle Blogs

Recent comments

October 2018

dbms_log

I’ve been a long time (though occasional) user of the undocumented dbms_system package, typically using it to write messages or insert break lines in trace files (or the alert log). Thanks to an email from Cary Millsap I’ve recently discovered that the procedures for writing to trace files have been copied to a separate dbms_log package – which is nice because some of the things in dbms_system shouldn’t be made available to general code, for example the procedure kcfrms which resets a number of the “max time” columns in various dynamic performance views.

Ansible tips’n’tricks: even more output options

In my last post I wrote about the “debug” option to format Ansible output differently. I came across this setting simply by searching the usual developer forums for an alternative Ansible output option.

Having found out about the “debug” option made me curious, especially since there wasn’t an awful lot of documentation available about additional alternatives. Or so It thought before writing this post, there is actually, as you will see later. So to recap what I had so far: I noticed “skippy” in my distribution’s /etc/ansible/ansible.cfg although it is commented out. And I found the “debug” option via my favourite search engine, and there is the “default” as well.

There surely had to be more …

This wasn’t quite good enough for me and I started to wonder if there were more of these callbacks. Here is my Ansible version in case some of these callbacks might be quite recent:

Installing an #Exasol 6.1 Cluster on VirtualBox

After having installed the latest VirtualBox version, an ISO file with the latest Exasol version has to be downloaded. The machine hosting VirtualBox should have at least 16 GB RAM and 80 GB free disk space in order to run a 2+1 Cluster with 3 data nodes and one license server. I’m doing it on my Windows 10 notebook.

ODC Appreciation Day: Reduce CPU usage by running the business logic in the Oracle Database

A new blog post on the Databases at CERN blog to think about:

Where to run business logic: in the database or another tier?

What language for coding business logic: SQL, PL/SQL, JavaScript?

Guess how to reduce licensing costs? https://db-blog.web.cern.ch/blog/franck-pachot/2018-10-odc-appreciation-day-reduce-cpu-usage-running-business-logic-oracle

ODC Appreciation Day : Reduce CPU usage by running the business logic in the Oracle Database

ODC Appreciation Day–LOB compression

LOBs tend to be large. Well duh…it’s right there in the name! “Large Object”. So one of the cool things I like with the SECUREFILE option in recent releases of Oracle Database is the ability to compress LOBs. Here’s a quick demo of that in action:

Generate Oracle SQL Monitoring Reports as HTML using SQL Developer v18.3 (no Flash needed)

The Oracle SQL Developer team has released version 18.3 of this tool. My favorite new feature in this version is its ability to save SQL Monitoring reports in HTML format! Adobe Flash is finally not needed for sharing graphical SQL Monitoring reports.
Here’s an example output, it looks pretty nice and clean:
The report is reasonably navigatable, has tooltips (useful for identifying wait classes for example) and you can also rearrange columns by dragging them left or right with your mouse.

Generate Oracle SQL Monitoring Reports as HTML using SQL Developer v18.3 (no Flash needed)

The Oracle SQL Developer team has released version 18.3 of this tool. My favorite new feature in this version is its ability to save SQL Monitoring reports in HTML format! Adobe Flash is finally not needed for sharing graphical SQL Monitoring reports.
Here’s an example output, it looks pretty nice and clean:
The report is reasonably navigatable, has tooltips (useful for identifying wait classes for example) and you can also rearrange columns by dragging them left or right with your mouse.

Generate Oracle SQL Monitoring Reports as HTML using SQL Developer v18.3 (no Flash needed)

The Oracle SQL Developer team has released version 18.3 of this tool. My favorite new feature in this version is its ability to save SQL Monitoring reports in HTML format! Adobe Flash is finally not needed for sharing graphical SQL Monitoring reports.
Here’s an example output, it looks pretty nice and clean:
The report is reasonably navigatable, has tooltips (useful for identifying wait classes for example) and you can also rearrange columns by dragging them left or right with your mouse.

Generate Oracle SQL Monitoring Reports as HTML using SQL Developer v18.3 (no Flash needed)

The Oracle SQL Developer team has released version 18.3 of this tool. My favorite new feature in this version is its ability to save SQL Monitoring reports in HTML format! Adobe Flash is finally not needed for sharing graphical SQL Monitoring reports.
Here’s an example output, it looks pretty nice and clean:
The report is reasonably navigatable, has tooltips (useful for identifying wait classes for example) and you can also rearrange columns by dragging them left or right with your mouse.

Hybrid Fake

Oracle 12c introduced the “Hybrid” histogram – a nice addition to the available options and one that (ignoring the bug for which a patch has been created) supplies the optimizer with better information about the data than the equivalent height-balanced histogram. There is still a problem, though, in the trade-off between accuracy and speed: just as it does with height-balanced histograms when using auto_sample_size Oracle samples (typically) about 5,500 rows to create a hybrid histogram, and the SQL it uses to generate the necessary summary is essentially an aggregation of the sample, so either you have a small sample with the risk of lower accuracy or a large sample with an increase in workload.