The challenge to prepare the graduates for working in a constantly changing environment like software engineering requires an effective learning framework. This chapter presents a tool, integrated in the Moodle learning management system, that allows students to train the process of designing relational databases. The tool also allows them to practice with SQL queries that are executed over relational databases previously designed. This chapter also describes the result of a qualitative analysis of its use in an engineering course offered at the University of Valladolid and focused on the teaching of the Web applications development. The results of the refereed study reveal that the tool was found useful by both students and teachers to support the teaching and learning process of relational databases.
TopBackground
The relational database was born in 1970 when E.F. Codd, a researcher at IBM, wrote a paper outlining the process of defining such a database. Since then, relational databases have grown in popularity to become the standard (Sumathi & Esakkirajan, 2007) (Churcher, 2012).
Originally, databases were flat. This means that the information was stored in one long text file, called a tab delimited file. Each entry in the tab delimited file was separated by a special character, such as a vertical bar (|). Each entry contained multiple pieces of information (fields) about a particular object or person grouped together as a record. The text file made it difficult to search for specific information or to create reports that included only certain fields from each record. An example of the file created by a flat database could be the following (shown in Box 1).
| Lname, FName, Age, Salary|Page, Jane, 30, $3200|Doherty, Mark, 43, $4320|Murray, Peter, 34, $2715|Roland, Richard, 40, $2730 |
With such a file, it would be necessary to search sequentially through the entire file to gather related information, such as Lname or salary. On the contrary, a relational database allows to easily find specific information as well as to sort information based on any field and to generate reports that contain only certain fields from each record. Relational databases use tables to store information. The standard fields and records are represented as columns (fields) and rows (records) in a table.
By using a relational database, information can be quickly compared because of the arrangement of data in columns. The relational database model takes advantage of this uniformity to build new tables out of required information from existing tables. This way, it takes advantage of the relationship of similar data to increase the speed and versatility of the database.
Relational databases are created and manipulated by using a special computer language, named the Structured Query Language (SQL), which is the standard for database interoperability. SQL is the foundation for all of the popular Database Management Systems (DBMS) available today, from Access to Oracle.