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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