Relational model, Database Management System

Assignment Help:

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.


Related Discussions:- Relational model

Create student database and retrieve course taught by king, Create student ...

Create student database and retrieve course name taught by king? STUDENT (name, student#, class, major) COURSE (course name, course#, credit hours, department) SECTION (secti

External failure-database recovery and security, External failure : A failu...

External failure : A failure can also result because of an external cause, such as earthquakes, fire, floods, etc. The database must be duly backed up to avoid troubles occurring d

Determine object representation, Determine object representation As a ...

Determine object representation As a designer, we must choose properly that when to use primitive types in representing objects and when to combine groups of related objects,

Name the metrics for selecting top algorithm, Name the metrics for selectin...

Name the metrics for selecting top algorithm There are a number of metrics for selecting top algorithm: i) Computational complexity: Computational complexity refers to eff

What are the four main characteristics of the database, What are the four m...

What are the four main characteristics of the database approach? The four major characteristics of the database approach are: 1. Self-describing nature of a database system. 2.

The concurrent transactions, The Concurrent Transactions  Almost every ...

The Concurrent Transactions  Almost every commercial DBMS support multi-user environment. Therefore, allowing multiple transactions to proceed concurrently. The DBMS must make

What subschema expresses, What subschema expresses ? A subschema expres...

What subschema expresses ? A subschema expresses the external view. (External schemas are called also called as subschemas)

Define thomas write rule, Define Thomas write rule Thomas' write rule: ...

Define Thomas write rule Thomas' write rule: The Thomas' write rule is a modification of timestamp-ordering protocol for concurrency control. Assume that transaction T i issue

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd