Data Normalization In Database Data normalization is the organization and structuring of database tables in such a way that the same data is only stored once and at the right place. Instead of putting the various types of data into a single table and creating various errors through repetition and inaccuracy, normalization guarantees the logical distribution of data among several related tables. This assists in consistency, minimizes redundancy and storage wastage and simplifies data updating or querying. Normalization of data also means that once you modify the content (e.g. address of a user), you will only need to make changes in one place.