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Database Normalization Basics

There are 3 primary reasons why a database should be normalized: It brings data integrity to the tables (entities). This facilitates proper inserting, updating, and deleting of data thereby preventing data anomalies. If a table is not normalized it runs the risk of inconsistent data, data redundancies, and inconsistent result sets.   To create entity relationships thereby providing referential integrity. Referential integrity ensures that relationships between tables remain consistent when entities are altered. To avoid having one set of users with a biased view of the data. For example a marketing department may view the data in line with their revenue needs rather than having an objective view of the data as it applies to the entire organization. We begin by analyzing the current relationships that exist between the attributes within each entity. Apparent in the Orders entity is the repeating data in the ITEM_NAME, ITEM_DESCRIPT, QUANTITY, and PRICE attributes. We break the en