How data redundancy is handled in the relational database model?

 Data redundancy leads to data anomalies. These anomalies can destroy the effectiveness of a database. The relational database makes it possible to control data redundancies by using common attributes that are shared by tables, called foreign keys. The proper use of foreign keys is crucial to exercising data redundancy control. However, it is worth noting that, in the strictest sense, the use of foreign keys does not eliminate data redundancies because the foreign key values can be repeated many times.