Today this website got a new theme.
Author Archives: Karsten Meier
JavaScript Incompatibilities in Webapps
(Deutsch) Zwei Inkompatibilitäten aus einem praktischen Projekt: Datumsfunktionen sind bei älteren Android-Geräten unvollständig, und die prompt-Methode wird von Microsoft still unterdrückt. Continue reading
Nokia Asha from a developers point of view
I was among the winners of the Nokia Asha Touch Competition 2012. I was awarded for the feedback I have given on the new Nokia developer tools. From the laudation: “for his very focused and relevant feedback around core app … Continue reading
Codename One – Swap Grid Cells
What is Codename One? The platform “Codename One” offers operating system-independent development of apps for smartphones. An important component is a library for user interfaces. Codename One is a successor of LWUIT, which in turn uses concepts of the Java … Continue reading
Presentation About Rails Database Optimization
Here are the English slides about how to optimize database queries in Ruby On Rails. I have showed this presentation at the Ruby User Group Hamburg at the 9th August 2012.
(Deutsch) Ruby On Rails Datenbankoptimierung Teil 2
[Zu Teil 1] Verknüpfungen mit dem SQL-join Relationale Datenbanken erlauben es, Tabellen miteinander zu verknüpfen. In SQL gibt es für diese Verknüpfung das Schlüsselwort “JOIN“. Eine solche Verknüpfung kann theoretisch sehr frei spezifiziert werden, in der Praxis wird man fast … Continue reading
Optimize the Ruby-on-Rails database – part one
Reduce the number of database queries A typical web application does many database queries before it delivers the response page to the web browser. The application needs to wait for the response of each of these database queries. It gets … Continue reading
Modification of Ilias Features
Examples for redesign The learning management system Ilias can be redesigned with skins. (See previous blog entry.) But an Ilias skin can even change the functionality. I show a few examples. Login Page You find the templates for login, … Continue reading
Attribute or Property?
Sorry, not yet translated
Rails ActiveRecord: count, length or size?
The object oriented database layer “ActiveRecord” offeres three different methods to determine the number of objects: count(), length() und size(). Alle drei Methoden liefern das gleiche Ergebnis. Was nehmen wir wann? Warum ist es überhaupt wichtig? Nimmt man die falsche … Continue reading