Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Explain the Relational Model in DBMS?
In relational models, the data is maintained in the form of a two-dimensional table.
Information is stored in the form of rows and columns. The basic structure of this model is tables. Generally, tables are called relations in the relational model.
Example
Let’s consider a student table
| Std-Id | Std-Name | Age | Branch |
|---|---|---|---|
| 101 | Hari | 20 | CSE |
| 102 | Pinky | 22 | EEE |
| 103 | Bob | 20 | CSE |
| 104 | Lucky | 21 | ECE |
Features
The features of Relational Model are as follows −
Tuples − Each row in the table is called a tuple. A row contains all the information about any instance of the object. In the above example, each row contains all the information regarding each student.
Attribute or field − Attributes are property which defines the table or relation. The values of the attribute should be from the same domain. In the above example, we have different attributes of the student like Id, name, age, branch, etc.
Advantages
The advantages of the relational model are as follows −
Changes in a table’s structure do not affect data access.
Tabular view improves conceptual simplicity which promotes easier database design, implementation, and management.
It has a referential integrity control that ensures data consistency.
This model is simpler as compared to other networks.
This model is easily scalable because we can add as many rows and columns, we want.
Disadvantages
The disadvantages of the relational model are as follows −
Hardware overheads.
Bad design.
2K+ Views
