Database design using a web based e learning tool

Database design using a web based e learning tool

ACME DB is a web based e learning tool for skills training and automatic assessment of main database course topics. This tool is composed of a set of correction modules each one designed for a specific type of problems. Among them, entity relationship diagrams, relational database schemas, normalization, relational algebra and SQL. In this paper we describe how ACME DB has been used in teaching/learning of database design in our university and how it has influenced in the academic results. 2. Related work In this section we give a quick overview of the database design contents and a description of the teaching methodology applied in our university. Afterwards, we briefly review the different e learning tools described in the literature to support teaching and learning contents in database design. 2.1. Teaching Database design Database design is one of the main topic of any introductory database course. The creation of a database requires a design process to define types, structures and constraints for the data to be stored in the computer. This process can be summarized in four main steps: First, the analysis of the requirements of the real world situation that has to be represented. Second, the definition of the conceptual schema that gives a high level description of the database and the requirements that data must satisfy. The most popular approach for model considers the world as a set of entities and the relationships between them. Third, the definition of a logical design which gives a high level schema implementable on a data model used for database management. It represents the database as a collection of relations where each relation resembles a table of values. To create relations with no redundant data, with an efficient data organization and that can be modified in a consistent and correct manner, a normalization process is applied. Fourth, the definition of a physical design which represents the internal data storage details. When all these concepts are acquired, students have the knowledge required to implement a relational database schema using any one of the available Database Management System (DBMS). 2.2. Database design in our University The methodology applied in the database courses of our university is the following. There are lecture sessions, where the teacher introduces main theory concepts and laboratory sessions where exercises are assigned to the students to put in practice these concepts. These exercises are related with real cases and take student trough the different stages of the design process. To star, the student creates conceptual models for small problems. Once these concepts are acquired more complex exercises are assigned. The next step is devoted to logical design concepts. The student 33 transforms a conceptual model into a logical model targeted to a relational database implementation. Students learn to map a conceptual model into a logical model that can in turn be readily transformed into a relational database schema. At this point, the central concepts of the relational model (domains, keys, integrity constraints, and so on) are engaged. Finally, the database schema is created. The student defines the tables, with the corresponding attributes, primary and foreign keys, etc. A good strategy to acquire database design skills is to solve exercises similar to real world problems. With this purpose different exercises are assigned to the students. The most critical issue is the time required to correct these exercises. Moreover, if we consider that the solutions are not unique. To establish a trade off between the number of exercises and the time required to correct them, we gave to the students a list of exercises and only some of them were corrected in the class. In addition, two of these exercises were assigned to the students as homework and then they were corrected by the teacher. The main drawback of this strategy was that students only solved the assigned problems. Due to the importance of practice in the context of these courses and considering the requirements of the new European Higher Education Area, we decided to integrate e learning tools in the applied methodology in order to overcome the detected limitations. Fortunately, the functionalities of our e learning platform, ACME, satisfy these requirements. In addition, ACME provides support for the course management, student tracking, etc. For all these, we developed the modules needed to support the automatic correction of ER diagrams, relational database schemas and normalization. In this way, we will be able to support in a same environment all the functionalities required to cover the database design needs. This new environment, denoted ACME DB, is described in Section 3. 2.3. Database design Tools

Free download research paper


JMathNorm-Database Normalization Tool Using Mathematica