Two colleagues wanted to try out Kubernetes and more specifically deployment of an application on Kubernetes that was not entirely trivial. One that consists of at least two Pods – one running a database and one running an application. A little internet browsing brought me to a single YAML file […]
I busted the 12 – The Myths of IoT
Internet of Things (IoT) is for many technology-enthusiast the single most important thing that has ever happened. The impact of this technology on our lives is growing close to mythical proportions. Working in this industry for years, made me encounter some of the myths and irrational expectations of IoT. Some […]
Which tools and technologies are new and exciting, proven, growing stale–report from Devoxx 2022
A conference such as Devoxx is a great opportunity to get inspired into trying out tools and technologies that may not or only be vaguely be known as they are mentioned or even demonstrated by presenters or discussed in the hallways of the movie theater where the conference is taking […]
Reflections from Devoxx 2022–on software engineering today
End of day two. So many topics already were presented, demonstrated, discussed, tried out to and by me. This article is just a very brief overview of what caught my attention. And what I will have to look into in more detail – or not in some cases. Containers and […]
One click free browser based Oracle Database environment with Gitpod
This article describes how you can run your very own Oracle Database from your browser using Gitpod. With a free account (50 hours Gitpod use per month), you can open this URL to launch a workspace that contains Oracle Database 21c XE along with VS Code, Oracle Developer Tools extension […]
Adding Podman to my VM with Minikube (part 2)
For a demo, I needed an environment with Minikube, using the Podman driver as an alternative container runtime to the Docker driver. In my previous article, I shared with you the steps I took, to get Podman in combination with Kubernetes (Minikube), working on my demo environment. [https://technology.amis.nl/recent/adding-podman-to-my-vm-with-minikube-part-1/] In this […]
Apache NiFi: Monitoring metrics and provenance events using Azure Log Analytics
There are several cases where you might want to use Azure Log Analytics to monitor your NiFi instances. An obvious one is when NiFi is running in Azure. Azure Log Analytics can also be used as single monitoring/alerting solution for multiple applications making operations easier by providing a single interface […]
Things Conference 2022 – Implementing IoT at Scale
I had the pleasure of visiting the The Things Conference 2022, the largest LoRaWAN event in the world. Organized by Things Industries in Amsterdam on September 22 and 24. The conference hosted about 1500 IoT professionals, 50 exhibitors, and 70 speakers. On Thursday and Friday, 22 – 23 September, I […]
Booting up–even quite senior – laptops with Ubuntu Linux OS using Rufus
The challenge was as follows: provide a handson workshop environment – consisting of nothing more than a browser connected to our office’s Wifi network – for visitors to the Open Day we organized at my company. However, all I had to work with was a bunch of really old laptops […]
First steps with Gitpod – great for try out, quick open source contributions and for workshops
Gitpod.io is a SaaS for software developers (that can also be used in self-hosted mode on Kubernetes). Gitpod makes workspaces available – typically based on a Git repository – with tools to develop and build software. A workspace is an ephemeral (not long lasting) Linux environment that I can access […]
Adding Podman to my VM with Minikube (part 1)
For a demo, I needed an environment with Minikube, using the Podman driver as an alternative container runtime to the Docker driver. Lucky for me, I had the configuration for such an environment using Vagrant and Oracle VirtualBox. In the past, I already set up such a demo environment, available […]
Oracle Database 23c–new feature highlights (release February 2023?)
Based on the fascinating Twitter thread by Philipp Salvisberg covering the presentation by Gerald Venzl at DOAG 2022 I would like to mention a few of the features that apparently will be part of Oracle Database 23c – the new Long Term Support release (succeeding 19c) that has a beta […]
Oracle Cloud’s marching order: win developers’ hearts and minds
There are two public cloud. AWS and Azure. That is not actually the case – but that is how sometimes it may seem. A third cloud is frequently listed alongside the two main players. A cloud that has made serious efforts to be seen by developers and architects. By somehow […]
Build JHipster application for and Run on Docker or Podman
For the Open Day we organize shortly for our family, friends, neighbours and other interested parties, my colleagues create a custom web application to support our QR Scavenger Hunt through the offices and surrounding premises. This (progressive) web application is created using JHipster – leveraging Java, Angular, Spring, PostgreSQL and […]
Run "docker-compose" on Oracle Cloud Infrastructure Compute using Podman
Running “docker compose” in a VM on Oracle Cloud Infrastructure is perhaps not the ideal way to go – which probably would be OKE (Kubernetes) in order to benefit most from modern container infrastructure features and leverage the underlying VMs the most. However, sometimes falling back on what works and […]
Installing Ubuntu Desktop 22.04 LTS, Visual Studio Code and Node.js on a virtual machine using Vagrant and Oracle VirtualBox
For a TypeScript training, I needed an environment with Visual Studio Code and Node.js (a JavaScript runtime). On my Windows laptop, I wanted to create an environment with Ubuntu as guest Operating System, Visual Studio Code and Node.js available within an Oracle VirtualBox appliance. In my previous article, I shared […]
Migrating Oracle Enterprise Edition database To Standard Edition using Transportable Tablespaces
Introduction Oracle database Standard Edition (SE) has the main features of a RDBMS database and cost significantly less than Oracle Enterprise Edition (EE). Migrating a database from Oracle Enterprise Edition to Standard Edition can be a consideration ifthe Enterprise Edition options or features are not used (or not required) in […]
Azure API Management: Integration with Standard Logic Apps
In January 2022 there was a blog published on the Microsoft Tech Community that demonstrates how to integrate Azure API Management with Logic Apps (Standard). As mentioned in that blog, the functionality to import workflows in Logic Apps (Standard) is not yet available in API Management, only Logic Apps running […]
Installing Ubuntu Desktop 22.04 LTS on a virtual machine using VirtualBox
For a TypeScript training, I needed an environment with Visual Studio Code and Node.js (a JavaScript runtime). On my Windows laptop, I wanted to create an environment with Ubuntu as guest Operating System, Visual Studio Code and Node.js available within an Oracle VirtualBox appliance. In this article, I will share […]
Delay in establishing RAC Database connections after upgrading from Oracle 11g.
After upgrading to Oracle 12c, 19c, database connections take a long time (10 sec or more), before the connections are established. The connection time was less than 0.5 sec in 11g. This is caused by a setting in the used Oracle Clusterware/Grid Infrastructure service names for the database. The AQ […]
Pseudo Change Timestamp–Finding recently changed table rows using Flashback Version Query to provide a surrogate last_changed column
My challenge: replicate changes from database A to database B, once per day. The tables involved are pretty big (100M records). I really would not want to process them all into database B. However, the tables do not have a LAST_DATE_MODIFIED column that has a timestamp that is updated with […]
Quick Start with initially free Low Code Front End Development using Retool against ElephantSQL PostgreSQL
Front end development can be an art. An almost pixel by pixel design, a careful crafting UX or even CX. And there is a time and place and technology set for that. And there is a range of front end applications that may not require or even justify that same […]
Quick start with free managed PostgreSQL database on ElephantSQL
This article shows you can quickly get started with a free, managed PostgreSQL database with a table full of country data (using ElephantSQL). ElephantSQL is a hosted, managed PostgreSQL service from the team that also provides CloudKarafka and several other nice services. It is a breeze to get going. The […]
Is RHCSA still relevant when you use the cloud?
Last week I passed for my RHCSA exam (EX200) [1]. While I was studying for the exam, I asked myself which parts of this exam are still relevant when you use Linux servers and Linux containers in the cloud and which parts are not. Assumptions In the cloud, we prefer: […]
Supabase for Persistence and Server to Client Push in Vanilla HTML/JavaScript web application–a step by step guide
Supabase provides a cloud based backend service to web applications. That means that any (static) web application can use Supabase for user authentication and data persistence. Supabase provides a server to client) push notification service and it has server side serverless functions that can for example handle web hooks (triggers […]
Steampipe–analyze data from cloud, file, platform, IaC using SQL queries
In our daily work we are dealing with data from many sources. Data in CSV files, from Cloud APIs, in mail servers, configuration files, Terraform plans, in logging systems, source code repositories and many more. Different formats, access methods, tools. And retrieving data from one such source can be challenging […]
Linux background process and redirecting the standard input, output and error stream
Often, I use a Linux shell script that executes several commands. Sometimes you don’t want to wait for a command to end and you want the next command to immediately run after the previous one is started. In my previous article I mentioned such a situation, with regard to preparing […]
Apache NiFi: Importing and exporting parameters
When you import a new process group or upgrade an existing one, missing parameters contexts and parameters will automatically be added. The new parameters will be filled with values from the environment where the process group was committed to the Registry (except sensitive parameter values). This is usually a development […]
Creating a minimal container image for a Go application
How hard can it be – to create the smallest possible container image to run a Go application? It is not hard to create a container image that contains an binary executable file – and that is what a Go application turns into during the build process. However, that does […]
Apache NiFi: Having fun with Jolt transformations
Jolt is a Java library which can be used to transform JSON to JSON. A Jolt transformation specification itself is also a JSON file. You can use it in products such as Apache NiFi and Apache Camel. In this blog post I’ll describe my first experiences with Jolt transformations. For […]
Apache NiFi: JSON to SOAP
Apache NiFi is a powerful open source integration product. A challenge you might encounter when integrating systems is that one system can produce JSON messages and the other has a SOAP API available. In this blog post I’ll show how you can use NiFi to convert JSON input to a […]
Sorting an Angular Material table – how to use MatSort and sortingDataAccessors
Angular Material provides the MatSort directive as an easy way the include interactive sorting in the tables of your application. In this blogpost I will show the best way to add sorting to your Material table. In addition, I will show how to use custom sortingDataAccessors to sort on nested properties and case insensitively, and how to combine different sorting requirements.
Apache NiFi: Automating tasks using NiPyAPI
Apache NiFi has a powerful web-based interface which provides a seamless experience between design, control, feedback, and monitoring. Sometimes however, you want to automate tasks instead of doing them manually using the UI. This does not only allow you to perform the tasks a lot quicker but it also helps […]
WebSinker–generic event detection for unhooked systems to trigger WebHook
Quite a few systems – business applications large and small – do not have support for WebHooks. That is: they do not offer the ability to register a URL as HTTP endpoint (WebHook) that the system will send requests to that inform the endpoint about relevant events. However, there are […]
AMIS DataSafe, the answer to Black Swan scenarios
How to be prepared for a black swan scenario?
Brief: What is Oracle Wallet?
An Oracle Wallet is an encrypted file that contains database credentials – username and password – for connecting to an Oracle Database. This avoids writing hard code user passwords in a shell script or in an application database configuration file. A wallet can also contain certificates – for example for […]
Apache NiFi: Avoid these common pitfalls
Apache NiFi is an easy to use, powerful, and reliable system to process and distribute data. It has a powerful UI which can be used for both development and operations. In addition, the NiFi Registry is available to make promoting software from one environment to the next, easy. In order […]
Adding Grafana to my VM with Minikube and Elasticsearch
For a demo, I needed an environment with Grafana. Lucky for me, I had the configuration for such an environment using Vagrant and Oracle VirtualBox. In the past, I already set up such a demo environment, available within an Oracle VirtualBox appliance, as I described in a series of articles. […]
Marrying Fn Functions to Dapr.io–leverage the power of the proxy
Project Fn provides a framework for creating and running serverless functions. It is the foundation for the Functions service on Oracle Cloud Infrastructure. Dapr.io is an open source project that provides a powerful personal assistant for any application and a distributed application runtime that especially shines with microservices. Some aspects […]
Query Past Generations in Oracle Database SQL – PI Day Special
Today is PI Day. March 14 or: 3-14 in the US. Of course it can be March 14th 2015 – 3-14-15 – only once but for some reason March 14 is baptized PI Day and is not unlike April Fool’s day the international day for nerdi stuff. You may want […]