Abstract:

Database design at the conceptual level using the Entity-Relationship (ER) model is often a difficult and complex task for novices. The subsequent step to map a conceptual data model to a logical one (e.g. relational data model) is not easy for beginners, either. Our experience with first-time learners shows that they often mechanically follow the mapping algorithms to perform the conversion without fully understanding the principles behind it. The end result is often wrong or incomplete. There seems to be a gap between their perceptions of the conceptual model and the logical model, which hinders their understanding of the mapping. This paper presents a study that evaluates the effect of a visualization tool, MySQL Workbench, in helping students advance their understanding and performance on mapping an Entity-Relationship Diagram (ERD) to a relational schema. Our study shows that a visualization tool like MySQL Workbench made learning more fun and students more engaged in the learning process, though some complained about the learning curve of the tool. Through the tool, students were able to see a connection between the two models, which helped them improve their performance on some mapping aspects. Our survey shows that, inadvertently, the tool also helped some students gain a better understanding of the conceptual data model. Based on our experience, the paper also presents recommendations on how to use the tool more effective in teaching ERD-relational schema mapping.

Keywords:

entity-relationship model, relational model, relational schema, entity-relationship diagram, visualization, ERD-relational schema mapping