Group 6 • What is data redundancy? Data redundancy occurs in database systems which have a field that is repeated in two or more tables. . . • Data redundancy leads to data anomalies and corruption and generally should be avoided by design. • Data normalization prevents data redundancy, and it also makes the best possible usage of storage. • Isolated data is a problem because it often is difficult to access data stored in separate files in different departments. The book uses this example- Assume that the student e-mail addresses exist in the Student files, and class room numbers (locations) are in the Schedule of Classes file. To send an e-mail message informing students about a room change, data is needed from both the Student file and the Schedule of Classes file, complicating things unnecessarily.