CH_DB_Normal_Notes.txt - Database normalization is the...

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Database normalization is the process of organizing the attributes and tables of a relational database to minimize data redundancy. Redundant data wastes disk space and creates maintenance problems. 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. There are a few rules for database normalization. Each rule is called a "normal form." Edgar F. Codd, the inventor of the relational model (RM), introduced the concept of normalization and what we now know as the First normal form (1NF) in 1970. Codd went on to define the Second normal form (2NF) and Third normal form (3NF) in 1971, and Codd and Raymond F. Boyce defined the Boyce-Codd Normal Form (BCNF) in 1974. Informally, a relational database table is often described as
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