Install PyGame on Fedora

The PyGame library is a wonderful tool for building games with Python. It lets you accomplish a great deal by simply managing events. You need to understand how to use Python functions, modules, and events to build games with this Python library.

You can download and install the PyGame library with the yum utility like this:

yum install -y pygame

It should generate the following list when you install it as the root user:

Loaded  (more...)

Enable HyperFIDO U2F Key on Linux

Recently, I bought the Hypersecu HyperFIDO K5 Key to help me secure access to several websites and services with U2F (“Universal Two-Factor Authorization”). This works fine on Windows, but with Linux things get a little complicated: The key isn’t accessible to all users by default. This has to be activated using udev rules, which is widely […]

Formatter-Einstellung für SQLcl

Dass die Häufigkeit meiner Beiträge zuletzt weiter abgenommen hat, mag dem regelmäßigen Leser aufgefallen sein und dafür gibt es - wie in solchen Fällen üblich - berufliche und private Ursachen (im weitesten Sinne steht Arbeit im Weg). Um aber nicht völlig zu verstummen hier mal wieder ein Link: Jeff Smith erläutert in seinem Blog, wie man eine SQL-Query in SQLcl mit dem Befehl "format buffer" automatisch formatieren lassen kann. Zusätzlich zeigt er, dass man die (more...)

Using VS Code for PL/SQL development

I've been using Sublime Text as my main editor for PL/SQL development for many years, but I'm now in the process of switching to Visual Studio Code (VS Code).

Some good reasons to use VS Code:
  • Multi-platform (Windows, OS X, Linux)
  • Free, open source
  • Lightweight, fast
  • Large ecosystem of extensions
  • Built-in Git support
  • Can be adapted to PL/SQL coding via a plsql language extension (syntax highlighting, go to/peek definition, go to symbol) and PL/SQL compilation (more...)

Generate Rows based on a Column Value

My requirement is the following:

In a database table the activity, start time and the number of repetitions is stored, but for the report this needs to be expanded. The number of repetitions dictates the number of rows per activity, each incremented by five minutes from the start time.
To get things going a simplified table is created, as well as some sample data.

create table activities
(activity varchar2(10)
,activity_date date
,no_of_reps number

insert (more...)

Data Vault 2.0 Online Training – Early Adopter

Finally you have an option to get authentic Data Vault 2.0 training online from Dan Linstedt!


Note to self: You can export highlighted text (e.g.: SQL code) easily from Notepad++ to RTF and/or HTML using  “Plugins” – “NppExport” – “…”. Voilá – there’s highlighted code in your Document, Presentation, Website, a.s.f.! Also, this:

Speaking at DOAG and RMOUG rocked

As I wrote a while back I was accepted to speak both at the User Group Leader summit at DOAG16 and at RMOUG Training Days.

The first one was a short presentation where I talked about a large bug in Oracle security and the need to patch and upgrade to not have that exposure. It was great fun as it was limited to a four-minute talk. I learned a lot from preparing for it as (more...)

Show greyscale icon as red

I have an editable tabular form using Apex’s old greyscale edit link icons:


The users complained that they currently have to click each link to drill down to the detail records to find and fix any errors; they wanted the screen to indicate which detail records were already fine and which ones needed attention.

Since screen real-estate is limited here, I wanted to indicate the problems by showing a red edit link instead of the (more...)

Font APEX between versions

Sometimes, it's the little things in an application that make users happy.

Sometimes, it's just the icon on a darn button, card, or menu that makes all the difference.

Surely by now you've encountered using icons within Oracle APEX, and we've come a long way since Theme 25. To get anyone up to speed, APEX 5.0 saw the introduction of Font Awesome baked into the builder, which is a reputable CSS icon library for (more...)

The Difference Between WHERE and HAVING Clause

What is the difference between WHERE and HAVING clause in SQL? Learn what they are and the differences in this article. Difference Between WHERE and HAVING Clause Both the WHERE and the HAVING clause are very similar and are used to restrict the rows that are returned in a SELECT query. The difference between WHERE […]

SQLcl: Make NULLs “visible”

One of the nice features in SQL Developer is to be able to define a value to replace NULLs (for display purpose only) in the data grids. Jeff Smith has a blog post about it in case you are interested.

You can achieve something similar in your SQLcl session by using set null some_string.

And here is  the output from a query after setting the system variable.


Filed under: Oracle, SQLcl Tagged: Oracle (more...)

#OUGN17 Row Pattern Matching with MATCH_RECOGNIZE

OUGN17 (the boat conference) rocked - and the boat didn't, thank goodness. I gave two talks about row pattern matching that were well received: two or three brave souls even went to both talks. I put my slides on the OUGN Google Drive page and on Slideshare.

Change UUIDs in VirtualBox

If you are anything like me you will have multiple virtualboxes running on your system. Sometimes you might want to run a copy of a virtualbox for different purposes. Like running an Oracle 11 Devdays instance as test environment but also running the same vbox for customer testing. If you copy the vbox and try to run it in the manager you’ll be presented with an error that a harddisk with the same UUID already (more...)

Get your virtual mojo on

I have for a few years created a play environment in a similar way. Getting a database installed in a VM is not too hard. But I found that I did it fairly often and not always in the same way and not always without having to resolve problems I know I had solved before but since forgotten the solution for.

Right, write everything down. Yes, it was time for that.

So I now have (more...)

Serielle und parallele Update-Verarbeitung

Jonathan Lewis hat gestern in seinem Scratchpad danach gefragt, wie es dazu kommen kann, dass ein anscheinend parallelisierbares Update seriell verarbeitet wird, und stellt dazu ein umfangreiches Beispiel zur Verfügung. Die richtige - oder zumindest eine weitgehend richtige - Antwort auf die Quizfrage hat offenbar Franck Pachot geliefert, der darauf hinweist, dass ein paralleles Update in 12.1 für Tabellen mit SecureFile LOBs nur möglich ist, wenn die Tabelle partitioniert ist. Der Herr Lewis bestätigte (more...)

ORA-01031 insufficient privileges Solution

Are you getting the “ORA-01031 insufficient privileges” error? Learn what causes this error and how to resolve it in this article. ORA-01031 Cause The cause of the ORA-01031 error is that you’re trying to run a program or function and you don’t have the privileges to run it. This could happen in many situations, such […]

A nice Descending Index Range Scan

I’ve been aware of some of the ways that Oracle database optimises index accesses for queries, but I’m also aware that you have to test each critical query to ensure that the expected optimisations are taking effect.

I had this simple query, the requirement of which is to get the “previous status” for a record from a journal table. Since the journal table records all inserts, updates and deletes, and this query is called immediately (more...)

Connect Developer Cloud Service to Slack with Webhooks

Johan Louwers shares a how-to on his blog showing you how to connect Oracle Developer Cloud Service to send notification to the popular Slack collaboration tool.

Check the detailed steps here.


You can use similar steps to hook DevCS to other collaboration services such as hipchat and Oracle Social Network.

More in the documantation.

FRM-93658 on Windows 2012 at runtime on Forms 12c Server

I don’t know about you guys but as we’ve doing more and more upgrades to 12c we’ve been seeing some bugs creeping up. So in hopes to assist in how to manage these bugs, we will be producing more posts to try to help you guys out. Thanks to Jan-Peter AuraPlayer’s Form’s Rockstar for leading the charge!

One thing we saw today in a few customers, was a strange crash that happened sometimes at runtime (more...)