What is a relational model?
A Relational Model describes how a Relational Database such as Oracle or SQL Server works. Tables in the Database consist of Columns. For example, a Table of Employees may consist of the Emp No and Emp Name columns (amongst others). There may also be a Dept table consisting of Dept Name and Dept No. In Each Case the tables have a primary key – the Emp No and Dept No respectively. A Third Table which specifies which Employees are in Which Dept may contain the ‘foreign keys’ dept no and emp no. Using the ‘relationship’ between the primary and foreign keys you can look up each department name, and each employee name within that department from the Employee and Department tables respectively. Hope this is clear enough.
