Johannes SchildgenRegensburg University of Applied Sciences | OTH Regensburg · Computer Science
Johannes Schildgen
Prof. Dr.
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22
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Introduction
Publications
Publications (22)
For its third installment, the Data Science Challenge of the 19th symposium “Database Systems for Business, Technology and Web” (BTW) of the Gesellschaft für Informatik (GI) tackled the problem of predictive energy management in large production facilities. For the first time, this year’s challenge was organized as a cooperation between Technische...
Metadata management constitutes a key prerequisite for enterprises as they engage in data analytics and governance. Today, however, the context of data is often only manually documented by subject matter experts, and lacks completeness and reliability due to the complex nature of data pipelines. Thus, collecting data lineage—describing the origin,...
Zusammenfassung
Mit PowerPoint oder LaTeX Beamer erstellte Vorlesungsfolien sind meist statisch und dienen hauptsächlich der Präsentation von Lehrinhalten. Als Alternative dazu werden drei Erweiterungen für das HTML- und JavaScript-basierte Präsentationsframework reveal.js vorgestellt, die für mehr Interaktion in der Datenbankenlehre sorgen sollen:...
In computer science, game-based learning is an exciting and entertaining way to learn a programming language or coding fundamentals. MonstER Park is a game which applies this concept to entityrelationship models (ERM) an teach it in an easy, fun, and effective way. The plot of the game is about a theme park named MonstER Park that is opening soon,...
Lerne die Datenbanksprache SQL einfach während der Autofahrt, in der U-Bahn, beim Kochen oder Putzen. In diesem Hörbuch lernst du die Grundlagen relationaler Datenbanken und du erfährst, was ein ER-Diagramm, das relationale Modell und die relationale Algebra ist. Und natürlich lernst du alles zu SQL.
Die Sprache SQL besteht aus drei Teilen. Der er...
The rising adoption of NoSQL technology in enterprises causes a heterogeneous landscape of different data stores. Different stores provide distinct advantages and disadvantages, making it necessary for enterprises to facilitate multiple systems for specific purposes. This resulting polyglot persistence is difficult to handle for developers since so...
Bei der Informationsintegration, also dem Zusammenführen verschiedener Daten aus zwei oder mehr Datenquellen, gilt es die Heterogenität der Quellen aufzulösen und die gegebenen Schemata ineinander abzubilden. Besonders bei der Verarbeitung von Big Data in schemalosen NoSQL-Systemen, in denen heterogene Datensätze gespeichert sind, und die sich zusä...
It is simple to query a relational database because all columns of the tables are known and the language SQL is easily applicable. In NoSQL, there usually is no fixed schema and no query language. In this article, we present NotaQL, a data-transformation language for wide-column stores. NotaQL is easy to use and powerful. Many MapReduce algorithms...
Wide-column stores differ from relational databases in terms of their data model, schema flexibility and query method. NotaQL is a transformation language for wide-column stores that is powerful and easy to use. Complex transformations are expressible in only two or three short lines of code, and can be executed in an incremental fashion. In this p...
The goal of this paper is to increase the computation speed of MapReduce jobs by reducing the accuracy of the result. Often, the timely processing is more important than the precision of the result. Hadoop has no built-in functionality for such an approximation technique, so the user has to implement sampling techniques manually. We introduce an au...
Wir präsentieren SQL Island, ein neuartiges browserbasiertes Lernspiel, welches auf dem Konzept der Text-Adventures basiert. Nach einem Flugzeugabsturz landet die Spielfigur auf einer Insel. Man redet mit Bewohnern, sammelt Gegenstände und käpft gegen Bösewichte. Die Besonderheit bei diesem Spiel ist jedoch, dass der Spieler seine Figur lediglich m...
Background: SQL Island is mainly addressed to university students, to help them apply concepts as taught in database lectures, and is suited for exam preparation.
However, it was designed especially for computer‐science introducing courses in
schools. We consider writing SQL queries a good method to teach children how to
command a machine, focusing...
Many MapReduce jobs for analyzing Big Data require many hours and have to be repeated again and again because the base data changes continuously. In this paper we propose Marimba, a framework for making MapReduce jobs incremental. Thus, a recomputation of a job only needs to process the changes since the last computation. This accelerates the execu...
Many MapReduce jobs for analyzing Big Data require many hours and have to be repeated again and again because the base data changes continuously. In this paper we propose Marimba, a framework for making MapReduce jobs incremental. Thus, a recomputation of a job only needs to process the changes since the last computation. This accelerates the execu...
Stellen Sie sich vor, Sie landen auf einer einsamen Insel und die Bewohner verstehen nur die Sprache SQL. Das Spiel SQL Island (http://www.sql-island.de) dient zur Vermittlung und Übung von SQL-Grundlagen und wird durch die Eingabe von SQL-Anfragen gesteuert. Der Zweck des Spiels ist es, dem Spieler auf unterhaltsame Weise beizubringen, wie Daten i...
The Hadoop framework for MapReduce jobs is a very popular tool for distributed
calculations over big data. Working with Hadoop is simple: Define your input
data source and implement the two methods Map and Reduce. You don't need to care
about scheduling or fault tolerance. That's what the Hadoop framework does.
But analyzing big data can be very t...
Das MapReduce-Programmiermodell ermöglicht die skalierbare Analyse und Transformation großer Datenmengen. Wir stellen das auf MapReduce basierende Marimba-Framework zur einfachen Entwicklung von inkrementellen, selbstwartbaren Programmen vor, welche bei Änderung von Quelldaten eine vollständige Wiederholung des MapReduce-Jobs vermeiden. Marimba wir...
