Different types of Data Models in DBMS

            

Data Models

Handwritten Notes- Click Here

A Data Model defines how data is organized, stored, related, and accessed in a database.

Types of Data Models in DBMS

  • Hierarchical Data Model
  • Network Data Model
  • Relational Data Model
  • Entity-Relationship (ER) Model
  • Object-Oriented Data Model
  • Object-Relational Data Model


1. Hierarchical Data Model 

The Hierarchical Data Model organizes data in the form of a tree structure.

  • Each child record has only one parent record.
  • A parent record can have multiple child records.
  • It mainly represents a one-to-many relationship.
  • Data retrieval is very fast in the hierarchical model.                                 Company

                  |

          Department

            /                  \

   Emp1                      Emp2


2. Network Data Model
The Network Data Model is an extension of the hierarchical model. It represents data using a graph structure.

    • A record can have multiple parent records.
    • A record can also have multiple child records.
    • It supports many-to-many relationships. 

            Course

            /               \
 Student                 Faculty

            \               /
             
               Project


3. Relational Data Model

The Relational Data Model stores data in the form of tables, which are known as relations.

A relational table consists of:

  • Rows – called tuples
  • Columns – called attributes
  • Primary Key – uniquely identifies records
  • Foreign Key – establishes relationships between tables 

Example

Customer Table

Customer Name

Street

City

Account No

Gowsi

East

Madurai

123

Tamil

West

Chennai

456

Jeji

North

Trichy

789

Jangu

South

Sivagangai

011


4. Entity-Relationship (ER) Model

The Entity-Relationship (ER) Model is mainly used for database design.

It represents data and the relationships among data using graphical concepts.

The main components are:

  • Entity – represented by a rectangle.
  • Attribute – represented by an oval.
  • Relationship – represented by a diamond. 


5. Object-Oriented Data Model

The Object-Oriented Data Model stores data as objects, similar to concepts used in object-oriented programming.

It supports concepts such as:

  • Classes-Suitable for handling complex data such as images, videos, and multimedia applications. 
  • Inheritance-Supports code reusability. 
  • Encapsulation-Provides better data abstraction

Video Explanation



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