TL;DR: a software release introduces changes in three areas: functional, non-functional and quality. Each change should contribute to identified objectives — and the contribution should be measurable. Product teams should strive for release statements that identify the changes, the objective they contribute to and the metric used for measuring their effect — to provide insight and the ability to influence to stakeholders and also to keep them rationally on track themselves.

The evolution of software applications happens in releases. Every new generation of a system is the result of the previous generation combined with the latest selected set of changes…

TL;DR: the true cost of a software feature includes a long tail of operational and maintenance cost that should be taken into consideration when first implementing the feature. The continuance or deprecation of features should be evaluated periodically, based on the actual usage and true value of the feature — compared to the cost of continuing it or killing it off.

What is the cost of having a child? This is a weird, perhaps impertinent of even unethical question. The comparison I want to make is that the cost of the initial conception or even the medical costs surrounding the…

TL;DR: see live demo of component on CodePen: https://codepen.io/lucasjellema/full/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 options. General classification in the Tour de France or the current league standings, the result of an election, the rank of the stars or the sequence of historical events, the best performing stocks, the top 10 longest rivers are just some examples of ordered data collections.

Whenever the end users of our applications…

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 obliged to also come up with more interesting dishes than my traditional set of meals. …

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 can be done with stand-alone application that have no backend. This article demonstrates a simple set up on Oracle Cloud Infrastructure — using a Serverless Function (that is not truly serverless because an instance and its variables are kept alive for 5–10 minutes after their last execution) and an API…

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 document, diagram, gameboard, technology radar, whiteboard etc. If that is the case, it would be useful if not necessary for the content to be synchronized across the browser environments.

With regular web applications, backed by a dedicated server side stack, this is fairly easily achieved. WebSockets or SSE can broadcast…

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 or some other Web framework or program in vanilla W3C technologies, D3 provides easy to use APIs to manipulate SVG objects and make them interactive and animated. Some easy steps to get going with SVG and D3.js are described in my earlier article on creating a simple game with D3.

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, on data and business logic. Creating games was never really on my mind. Until recently. I started to look for ways to visualize the data I worked with. And I ended up using quite a bit of JavaScript and especially Scalable Vector Graphics for creating appealing, animated and interactive graphics…

CODEX

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 it possible to run Java code (from) within the database. I have never been a big fan of stored Java procedures. The somewhat clunky integration was a large part of that. It seemed that apart for some very specific use cases, Stored Java had not much to offer. …

Here is a short story about a simple and incredibly common 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 and optimize (aka refactor) the query while maintaining its integrity? I am still in a development phase where I make quick changes and want to get quick feedback. The SQL is not yet embedded in an application — that may happen later. …

Lucas Jellema

Lucas Jellema is solution architect and CTO at AMIS, The Netherlands. He is Oracle ACE Director, Groundbreaker Ambassador, JavaOne Rockstar and programmer

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