Level-oriented universal visual representation environment

We propose a three-dimensional graphics engine targeted at simultaneous visualizing multiple data sets and simulations in progress using a number of different visualization methods. The user can navigate between different views in a way in which one would traverse a museum: by switching focus from one object to another or zooming out to include several objects at the same time. Related visual-izations are vertically organized into levels or floors, further enhancing the museum metaphor. Additional information and means of manipulating the visualized data or simulations are provided for the user in a form of a two-dimensional on-screen overlay and also with the use of various input devices, not only mouse or keyboard. L.O.U.V.R.E. proved to be a very efficient and useful tool when dealing with experiments on robotics simulations. This paper presents such usage, and al-so indicates other possible applications. We find that it fills a gap as an intuitive solution encompassing graphing, simulation and user interface at the same time. Its applications go far beyond computer science research into such fields as biology or physics

Extending DQL with Recursive Facilities

Object Relational Mappings reduce a gap between Relational Databases and programming languages. However, only the simplest operations are covered by the ORM frameworks. Most facilities provided by DBMSs are not usable via ORM. Among such features are recursive queries, introduced in SQL:99 standard. This paper presents integration of Recursive Common Table Expressions with Doctrine Query Language - a part of Doctrine ORM framework for PHP

On the Prevalence, Impact, and Evolution of SQL code smells in Data-Intensive Systems

ABSTRACT: Code smells indicate software design problems that harm software quality. Data-intensive systems that frequently access databases often suffer from SQL code smells besides the traditional smells. While there have been extensive studies on traditional code smells, recently, there has been a growing interest in SQL code smells. In this paper, we conduct an empirical study to investigate the prevalence and evolution of SQL code smells in open-source, data-intensive systems. We collected 150 projects and examined both traditional and SQL code smells in these projects. Our investigation delivers several important findings. First, SQL code smells are indeed prevalent in data-intensive software systems. Second, SQL code smells have a weak co-occurrence with traditional code smells. Third, SQL code smells have a weaker association with bugs than that of traditional code smells. Fourth, SQL code smells are more likely to be introduced at the beginning of the project lifetime and likely to be left in the code without a fix, compared to traditional code smells. Overall, our results show that SQL code smells are indeed prevalent and persistent in the studied data-intensive software systems. Developers should be aware of these smells and consider detecting and refactoring SQL code smells and traditional code smells separately, using dedicated tools