Relational model, Database Management System

A model in database system mostly defines the organisation of data or structure and a set of operations on that data. Relational model is a easy model in which database is represented as a collection of "Relations", where every relation is represented by a two dimensional table.  Therefore, because of its simplicity it is most commonly used. The following table shows a simple relation:

PERSON_ID

NAME

AGE

ADDRESS

1

Sanjay Prasad

35

b-4,Modi Nagar

2

Sharad Gupta

30

Pocket 2, Mayur

Vihar.

3

Vibhu Datt

36

c-2, New Delhi

Figure: A Sample Person Relation

Following are some of the benefits of relational model:

  • Ease of use

The easy tabular representation of database helps the user define and question the database conveniently. For example, you can simply find out the age of the person whose first name is "Vibhu".

  • Flexibility

As the database is a collection of tables, new data can be added and removed easily. Also, manipulation of data from several tables can be done simply using several basic operations. For instance, we can add a telephone number field in the table at Figure.

  • Accuracy

In relational databases the relational algebraic operations are used to influence database. These are mathematical operations and make sure accuracy (and less of ambiguity) as compared to other models.

Posted Date: 3/6/2013 5:14:08 AM | Location : United States







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