What does the term 'data redundancy' refer to?

The term 'data redundancy' typically refers to the duplication of data within a database. This occurs when the same piece of data is stored in multiple places, which can lead to inconsistencies and increased storage requirements. For example, if customer information is stored in several tables without proper normalization, any updates to that information would need to be made in multiple locations, increasing the risk of errors.

Maintaining data redundancy can sometimes be a deliberate choice in certain contexts like backup or enhancing performance, but in many cases, it is seen as an undesirable situation that can be mitigated through proper database design and normalization techniques. This is fundamentally why the definition encapsulates the concept of duplication in a database environment.