Normalization

In this session we will concentrate on normalization that is a very important step in database design mainly for relational DBMSs. The relational data model is simply based on a relation. When structuring data which is to be stored and the analyst must anticipate the required to access the data to meet unexpected requirements and to decrease redundancy. These can be achieved by the methods of normalization which gives a systematic way of boiling data structures down to their simplest possible forms.

Defination

Normalization is the procedure of organizing data in a database. This involves creating tables and establishing relationships among those tables according to rules designed both to protect the data and to make the database more flexible through eliminating two factors: inconsistent dependency and redundancy. Normalizing a logical database design includes organizing the data into more than one table. Normalization includes performance through reducing redundancy. Redundancy can direct to:

Inconsistencies – errors are more likely to occur when facts are frequent.

Update anomalies – Inserting, modifying and deleting data may cause inconsistencies. Normalization is a methodology which can be applied to data to ensure which a set of tables is derived which contains no redundant data. Normalization is a procedure of simplifying the relationship among data elements in a record. It is the alteration of complex data stores to a set of smaller, stable data structures. Normalized data structures are more stable, simpler and are easier to maintain. Normalization can thus be described as a procedure of simplifying the relationship among data elements in a record.