SuperNorm's Normalisation Website - Not just for Superhero's

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Databases And Normalisation:

Introduction -

Are you familiar with:

	Databases?
	Normalisation?
	Relationships?
	Referential Integrity?
	Cascade Update & Cascade Delete?

Do you want to know more? If so, then this site can help you.

Let's assume for the moment that you probably have a basic understanding of what a database is, otherwise you wouldn't be visiting this site. The following sections will provide some background history to the issue of Normalisation. After that we'll take a look at just what a database is and what types are in use in Information Systems today.

A Brief History of Normalisation

	Computing ‘guru’ - E.F. Codd developed and started using this technique at IBM in 1969.
	It was later called normalisation – the name is based on the need to make databases behave “normally”.
	Normalisation is based on Set Theory and Predicate Calculus.
	Normalisation can be applied to any data & database.

Why Normalise Data?

A definition of Normalisation is:
"In relational database design, the process of Normalisation is organising table data to minimise duplication..."

"Normalisation involves dividing a database into 2 or more tables and defining relationships between the tables. The objective of normalisation is to isolate data so that additions, deletions and modifications of data fields can be made in just one table and then propagated (spread) through the rest of the database using pre-defined relationships."

source - Webopedia, http://www.webopedia.com/TERM/n/normalization.html

Another Definition -
"Normalisation is the process of creating an...

	Efficient
	Reliable
	Flexible
	Relational structure for storing information."

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