Oracle VM is end-of-life and is, since March 2021, in extended support1. In looking for a replacement hypervisor AMIS has turned to KVM. Oracle itself also uses KVM, albeit its own brand of KVM, OLKVM, in Oracle Cloud and on the new versions of its Oracle Database Appliance. Topped with […]
Polling Rank – Interactive Visualization Component for Ordering Options
TL;DR: live demo of the Poll Rank component on Code Pen: https://codepen.io/lucasjellema/pen/NWpoBeM Bringing things to order is a common requirement. Making clear how things are mutually ordered, which comes first and which comes next, is often relevant. Order by value, by time or by preference are just some of the […]
What the Ether, part 1 – Ethereum
Just like in 2017, blockchain has been all the craze this year. With Bitcoin reaching prices over three times higher than the previous all-time high, everybody has been talking about cryptocurrency and blockchains. And one of the blockchains that has been taking the spotlight is Ethereum. That is why in […]
Visualizing Recipes in aid of Freshman Cooks
I am not the best cook in the world – it has been said. But I am making an effort to step up my game. My two sons have started participating in our family’s meal planning and with the rising quality and complexity of the meals they prepare I feel […]
Implementing Serverless Multi Client Session Synchronization with Oracle Cloud Infrastructure
TL;DR – Multi Client Sessions can be facilitated in a fully serverless fashion. Two players playing Tic Tac Toe or Chess, teams collaborating on a document or diagram, an audience witnessing a presenter’s demonstration – these are just examples where multiple distributed application instances should be kept in synch. This […]
Serverless Distributed Multi User Browser Session Synchronization
Assume a browser based (or desktop electron) stand alone, client side only application. Multiple users are working with that application at the same time, on their own laptops and at (possibly very) different locations, possibly across the globe. It is conceivable that they are working on a common object. A […]
Introduction to D3 Force for Simulation and Animation
The D3 library is great for creating rich and interactive data visualizations running in your browser. D3 is a JavaScript library that provides an easy bridge between the power of SVG (Scalable Vector Graphics) in the browser and your (and my) own JavaScript applications. Whether you use React, Angular, Vue […]
Review: Greenshot, Easy tool for screenshots
Is it possible to make something simple as making a screenshot easier? Yes, I have been using the free and open-source tool Greenshot for the past year. And I noticed missing the features when I got a new Windows image on my laptop. I would recommend installing this for anyone […]
Check for RunAs accounts in Automation Accounts
Introduction Some time ago, I wrote about the new preview feature in Azure Automation Accounts to use Managed Identities [1]. I think that it is useful to migrate to this new feature as soon as possible: managed identities are used in many places in Azure and it is better to […]
OBS Studio: How to record online presentations (Zoom, Teams, Webex, Meet, …)
Sometimes you want to record online presentations to maybe re-watch them later or share them with colleagues. It is not always possible to easily do this from within the tool which is used for the presentation. An easy alternative is to record such sessions using OBS Studio, a free and […]
Starting my own Game Studio–on the ease and the power of SVG
My very first steps in programming consisted of typing in the BASIC program listings from computer magazines. Usually very simple games with very poor UX. That probably is the closest I got to “creating” games. And then I went into computers professionally – with a primary focus on the backend, […]
Blog milestone: 200 blog posts, 1M page views!
This is my 200th blog post. Also I reached 1M page-views recently. In those 200 blog posts, I used approximately 325K words. An average non-fiction book is somewhere between 70K to 80K words. So that would amount to somewhere around 4 books. Why did I write so many blog posts, […]
Using a Managed Identity with Azure Automation Accounts
Introduction I think that every production environment in Azure uses Automation Accounts for f.e. scheduled tasks. Up to recently, you were forced to use the Run As user to do so. This solution has, however, two drawbacks. The first one is that this Run As user has way too many […]
Jenkins: Obtaining and displaying credentials
Jenkins is a solid CI/CD platform which has proven itself over the years. Many organizations use it to build, test and deploy their applications. In Jenkins it is possible to define credentials or to use an external credential store. You can then use these inside your pipelines and jobs. Direct […]
SonarCloud: OWASP Dependency-Check reports
SonarCloud is a hosted SonarQube SaaS solution which helps you with code quality management. It is free to use for open source projects. You cannot install 3rd party plugins in SonarCloud however. This puts some limitations on the kind of data you can put in SonarCloud. For Java this is […]
GitHub Actions and SonarCloud
GitHub Actions allow you to do most CI/CD tasks for free, directly from your GitHub repository. One of the challenges however is that there is no build-in facility like for example SonarQube to manage code quality. Luckily, SonarSource provides SonarCloud; a SonarQube SaaS offering which is free for public projects! […]
GitHub Actions: A first impression
I’m a regular user of GitHub. Recently I discovered GitHub also has a build-in CI/CD workflow solution called GitHub Actions. Curious about how this would work I decided to try it out. I had previously build a Jenkins Pipeline to perform several static and dynamic application security tests on a Java project […]
OWASP ZAP: A quick introduction to a versatile open source DAST tool
OWASP ZAP (Zed Attack Proxy) is an open source dynamic application security testing (DAST) tool. It is available here and has a website with documentation here. I recently encountered it when looking for open source security test tools to embed in a CI/CD pipeline (here). I was surprised by how versatile this tool […]
Delete play-resources from Azure using runbooks
Learning a new cloud can be frighting: do I configure this right? And, when I click here, don’t I end up with a huge bill at the end of the month? In general, these fears can be solved quite easily: when you follow along with a training, the trainer will […]
Executing JavaScript from PL/SQL in Oracle Database 21c with Multi Language Engine
Oracle Database Release 7 – end of 1993 – introduced PL/SQL as language for Stored Procedures, Functions and Triggers. This was just before I joined Oracle Corporation, in May 1994. I have made extensive use of PL/SQL. With Oracle 8i we saw the advent of the Embedded JVM that made […]
How to build [a CI/CD pipeline for] an Oracle Database application–kicking off a six part series
![How to build [a CI/CD pipeline for] an Oracle Database application–kicking off a six part series](https://technology.amis.nl/wp-content/uploads/2021/03/image-20.png)
Build is an overloaded term in the world of software engineering. Building software used to be mainly a fancy way of saying “programming”. Now after the construction of the code, the actual build process is kicked off, that takes the work from the individual programmer and turns it into something […]
How to unit test a SQL query?
A simple challenge: I am working on a SQL query. Not a trivial query. I am trying various approaches. I believe I may have found a solution that works. That produces the correct solution. How can I be sure? How can I try to further refine the query while maintaining […]
How to build an Oracle Database application (that supports APEX, Java, React or any other front-end) (1)
What’s in a name? A title is important and I hope that it describes well what I do want to share with you in this series of articles. It is not so much about how to use the back-end part (Oracle Database) or the front-end (Oracle APEX, Java, Node, React […]
Java Security: Open Source tools for use in CI/CD pipelines
It is often expected of a DevOps team to also take security into consideration when delivering software. Often however, this does not get the attention it deserves. In this blog post I’ll describe some easy to use, CI/CD pipeline friendly, open source tools you can use to perform several checks […]
SQL–Only Counting Records Sufficiently Spaced apart using Analytics with Windowing Clause and Anti Join
A nice SQL challenge was presented to me by a colleague. The challenges basically consisted of this table. A table contains records that describe login events. Each record has a login timestamp and the identifier of the person logging in. The challenge is to count “unique” login events. These have […]
How to build an Oracle Database application (that supports APEX, Java, React or any other front-end) (6)
Last time in “How to build an Oracle Database application (that supports APEX, Java, React or any other front-end) (5)”, I told you about Git, Subversion, Maven and Flyway. In this final article, I will discuss the following tools & methods: Oracle SQL Developer, utPLSQL, SonarQube, Perl, Ant and DevOps. Oracle […]
How to build an Oracle Database application (that supports APEX, Java, React or any other front-end) (5)
Last time in “How to build an Oracle Database application (that supports APEX, Java, React or any other front-end) (4)”, I told you about the Oracle SQL Developer Data Modeler. This time I will discuss the following tools: Git, Subversion, Maven and Flyway. Flyway The first tool I would like to […]
How to build an Oracle Database application (that supports APEX, Java, React or any other front-end) (4)
Last time in “How to build an Oracle Database application (that supports APEX, Java, React or any other front-end) (3)”, I told you about the Oracle Database and Oracle APEX. This time I will discuss Oracle SQL Developer Data Modeler. Oracle SQL Developer Data Modeler A book I can recommend is Oracle […]
How to build an Oracle Database application (that supports APEX, Java, React or any other front-end) (3)
Last time in “How to build an Oracle Database application (that supports APEX, Java, React or any other front-end) (2)”, I did show you the database structure. This time I will elaborate on the base tools, the Oracle Database and Oracle APEX. Oracle Database How to use it? I can tell […]
How to build an Oracle Database application (that supports APEX, Java, React or any other front-end) (2)
Last time in “How to build an Oracle Database application (that supports APEX, Java, React or any other front-end) (1)”, I gave you an introduction. This time I will elaborate on the database structure. Project folder layout The following top level directories may exist for every database application project: Directory Description […]
The Prototype Pitfall
TL;DR Prototyping is an essential way to determine the technical feasibility and functional desirability of features of a software system. There is a clear and present danger that the prototype is considered to be professional code, peer reviewed and production ready. This risk must be mitigated and anyone involved needs […]
Java Agent: Rewrite Java code at runtime using Javassist
You might want to change the behavior of a Java application at runtime without having to alter the original sources and recompile them. This can be done by using a Java Agent. Java Agents are used by several products. Dynatrace uses for example a Java Agent to collect data from inside […]
VNet peering in Azure
Introduction I looked into virtual network peering peering in Azure and I saw something that looked rather strange to me. Let me explain what it was, how VNet peering works and what you should be aware of from a security perspective. Situation I have two virtual networks: one for 10.1.0.0/16 […]
How to add a user in Azure Active Directory
Adding a user in Azure Active Directory caused some troubles: it didn’t work as I thought it would. Let me explain. Adding the user I went to Azure Active Directory, clicked “Users” in the left menu and added the user via “New user”. I filled in some information and clicked […]
Building my own Video Recorder–Automating Scheduled Streaming Video Recording on Windows 10
My objective: create a mechanism for recording streaming video on my Windows laptop on a preprogrammed timestamp and channel. My motivation: show that I can do this (using AutoIt, OBS, Windows Task Scheduler an Windows Sandbox) and create a way around the limitation of my current TV provider (Ziggo in […]
Playing with AI in Azure
When I was learning about Azure AI, I asked myself the question: “how far is AI? What can it determine – and what is impossible (yet)?” A nice tool that can give (partly) answers to that, is the website that Azure offers to scan images, it uses Azure Cognitive Services […]
Schedule Spotify Good Morning Playlist–using AutoIt and Windows Task Scheduler
I would like to have my Spotify playlist played to me every morning at 8AM sharp. Using the Windows Task Scheduler and an AutoIt script I can have the Spotify App started and subsequently automate the steps to run my preferred Spotify playlist. I can even wake my computer up […]
How to manage local IoT complexity with Azure IoT Edge
Whenever there is a more complex IoT solution with dependency on local business logic and the need for autonomous operations an edge device is quickly an important part of the solution. This article demonstrates the implementation of Azure IoT edge as part of two business cases that rely heavily on […]
Capturing those elusive Video Streams on Windows 10
I have tried to capture various video streams running in my browser using a plethora of screen capture and video recording tools. However, some streams prove hard to pin down. When I activate the recording tool – all of a sudden the video goes blank or black. And my recording […]
Automating actions on Windows – my first steps with AutoIt
I recently spent quite some time on getting to know Playwright – a great tool for automating virtually any operation performed in a browser. Playwright is great for automating testing web applications as well as for screen scraping (for data), tactical integration, RPA, prototyping and even customizing third party applications […]