Sachin noire 2024
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Transcript of Sachin noire 2024
I am heartily thankful to our respected director sir for giving me such a great opportunity to giving this presentation.
I am also thankful to our respect Teachers for helping me in making of this presentation.
Overview
• Data
• Information
• Database
• Data Model
Types of Data Model
1. Record Base model
•Relationship model
•Network Model
•Hierarchical Model
2.Entity Relationship Model
3.Object-Oriented Model
A data is known as the row fact which is stored in computersmemory and used by the user as the output.
Data
Data ModelA data model is a collection of concepts that can be used to describe the structure of a database.
Types of Data Models
1.Record Base model • A record based data model is
used to specify the overall
logical structure of the database.
• Each record type defines a fixed
no. of fields having a fixed
length.
Relational model
• In the relational model, data is
organized in two-dimensional tables
called relations.
Relations
No Course-Name Unit
CIS15 Intro to C 5
CIS17 Intro to Java 5
CIS19 UNIX 4
CIS51 Networking 5
Attributes
Tuples
Relations
• Attributes.
Each column in a relation is called an attribute.
• Tuples
Each row in a relation is called a tuple. A tuple defines
a collection of attribute values.
Network Model
In the network model, the entities are
organized in a graph, in which some entities
can be accessed through several paths
No Name ID Name Course
No Name Unit ID Name
DEPARTMENT
COURSES
STUDENTS
PROFESSORS
PROFESSORS
ID Name CourseNo Name Unit
ID Name
DEPARTMENT
No Name
COURSES STUDENTS
Hierarchical Model
2.Entity Relationship Model
• The E-R (entity-relationship) data model views the real world as a set
of basic objects (entities) and relationships among these objects
ER Model Basics
•Entity
•Entity Set
•Attributes
•Relationship
Entity
• entity is a thing in the real world with an independent existance. and
entity set is collection or set all entities of a particular entity type at any
point of time.