WEB BASED TOOL TO ENHANCE TEACHING LEARNING DATABASE NORMALIZATION
It has been difficult to motivate students to learn database normalization because students think the subject dry and theoretical. A web-based tool is developed to give students an interactive hands-on experience in database normalization process. The tool is suitable for relational data modeling in systems analysis and design and data management courses. This paper describes the web-based tool and its effectiveness in teaching relational data model. The effectiveness of the tool has been evaluated in surveys. The paper shows that the tool has a positive impact on students’ perception. Keywords: Database Normalization, Relational Data Model, Functional Dependency, Third Normal Form Introduction
Database normalization is a well developed field since the introduction of Codd’s seminal work on normal forms in 1970. Bernstein (1976), Diederich and Milton (1988), Concepcion and Villafuerte (1990), and Rosenthal and Reiner (1994) proposed algorithms and tools to synthesize a normalized database using functional dependencies. Maier (1988) indicated that relational data model theory (normalization) tends to be complex for the average designers. Jarvenpaa and Machesky (1989) and Bock and Ryan (1993) showed that relational data model leads to poor designer performance. The poor performance of normalization indicated that teaching normalization is a challenge to IS/IT educators. The classical database normalization technique has often relied on the definition of normal forms. Some database textbooks include normalization algorithms to find the canonical cover by removing extraneous attributes of functional dependencies (FDs) and then to convert each FD in the canonical cover to a relation/table (Silberschatz et al, 2002). The normalization algorithms often require extensive relational algebraic backgrounds that most IS/IT students lack. Most systems analysis and design textbooks rely on the definition of normal forms in their coverage of database normalization (Hoffer et al., 2005; Avison and Fitzerald, 2002). They simply give the definition of first, second and third normal forms (1NF, 2NF and 3NF) and hope that students will be able to apply the definitions and normalize a set of tables. These approaches may not be the best way to help many IS/IT students effectively understand the database normalization process. The main objective of this paper is to describe the web-based database normalization tool and its effectiveness in teaching and learning of normalization. The remainder of this paper is organized as follows. Section 2 describes the web-based tool, and section 3 illustrates research design and data collection procedure. The effectiveness of the web-based tool is evaluated and interpreted in section 4, and section 5 concludes the paper.
The Web-based Normalization Tool
It has been noticed that the decompositions happened when attributes on the right-hand side of functional
dependencies have more than one copy, and the number of the decomposed relations is exactly the same as the