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Normalization

What is Normalization?

Normalization, more commonly referred to as database normalization, is the process of organizing the attributes and tables of a relational database to minimize redundancy. The first step in creating and using a relational database (like MySQL) is to establish the database's structure. Database modeling is crucial for successful long-term management of information. You'll carefully eliminate redundancies and other problems that would undermine the integrity of your database.

Normalization involves decomposing a table into less redundant (and smaller) tables but without losing information; defining foreign keys in the old table referencing the primary keys of the new ones. The objective is to isolate data so that additions, deletions, and modifications of an attribute can be made in just one table and then propagated through the rest of the database using the defined foreign keys.

A typical example of normalization is that an entity's unique ID is stored everywhere in the system but its name is held in only one table. The name can be updated more easily in one row of one table.

Normalized tables, and the relationship between one normalized table and another, mirror real-world concepts and their interrelationships.

Normalized tables are suitable for general-purpose querying. This means any queries against these tables, including future queries whose details cannot be anticipated, are supported. In contrast, tables that are not normalized lend themselves to some types of queries, but not others.

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