This document discusses different types of data models, including object based models like entity relationship and object oriented models, physical models that describe how data is stored, and record based logical models. It specifically mentions hierarchical, network, and relational models as examples of record based logical data models. The purpose of data models is to represent and make data understandable by specifying rules for database construction, allowed data operations, and integrity.

1. Mrs. Maninder Kaur
professormaninder@gmail.com
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2. MODEL
A Model is representation of reality, ’real world’
objects and events and their associations.
A database model is an organizing principle that
specifies particular mechanism of data storage and
retrieval.
The model explains, in terms of services available to
an interfacing application, how to access a data
element when other related elements are known.
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3. Components of Data Models
Structure Part:
Consisting of set of rules according to which databases
can be constructed.
Manipulative Part:
Define the types of operation that are allowed on the
data.
Set of Integrity Rules:
Which ensures that data is accurate.
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4. Purpose of Data Model
To represent data.
To make the data understandable.
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5. Types of Data Models
Object Based Data Models
Physical Data Models
Record Based Logical Data Models
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6. Object Based Data Models
It use concepts such as entities, attributes and
relationships.
Types of Object Based Data Models:
* Entity Relationship
* Object Oriented
* Semantic
*Functional
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7. Physical Data Models
 It describe how data is stored in the
computer, representing information such as
record structures, record ordering and access
paths.
 Less no. of models are there.
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8. Record Based Logical Data Models
o It is used to specify the overall logical structure
of the database and to provide a higher-level
description of the implementation.
o Structured database in fixed formats.
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9. Types of Record Based Data Models
Hierarchical Model
Network Model
Relational Model
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10. Types of Record Based Data Models
Hierarchical Model
Network Model
Relational Model
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