Dbms

TOPIC: Types of Attributes and Types
of Relation

1. Welcome to our presentation Team members: Jannatul Marjan 181-15-1744 Kazi Masudur Rahman 181-15-1743 Mahdi Saifullah Srizan 181-15-1769 Rashaduzzaman Ananda 181-15-1870 TOPIC: Types of Attributes and Types of Releation CODE: CSE 311

2. Attribute Entities are represented by means of their properties is called attributes. Attributes are characteristics of an entity Student name Age Roll no Date of Birth Phone No. entity Attribute Attribute Attribute Attribute Attribute Bye the help of the attributes or properties we can say, he is a student. Entity: entity maybe an object with physical existance. Example : person,car,house or entity maybe an object with conceptual existance . Example : company, job, universities

3. Types of Attribute

4. Simple Atrribute Simple attributes are atomic values, which cannot be divided further . For example: Student Age Phone No. entity Atomic value Atomic value

5. Composite Atrribute Composite attributes can be divided into smaller sub parts. For example: Student Name entity Last Name First Name Address city House no Composite atrribute Composite atrribute

6. Derived Atrribute Derived attributes are the attributes that do not exist in the physical database, but their values are derived from other attributes present in the database.  For example: Student age entity Date of Birth Derived atrribute Store atrribute Bye the help of date of birth attribute a person age can be calculated An attribute that cannot be derived from another attribute is known as  stored attribute.

7. Single value Atrribute An Attribute that has only single value for an entity is known as single value attributed. For example: Student age entity Date of birth Single value atrribute Single value atrribute

8. Multi value Atrribute An attribute that can have multiple values for an entity is known as multivalue attribute   . For example: Student email entity Phone no Multi value attribute Multi value attribute A Student can have more than one phone no.. A Student can have more than one email address..

9. employee Age Employee id Date of Birth Phone No. entity diagrammatic representation of entity attribute relations Multi value attribute Name Last Name First Name Composite atrribute Derived atrribute Diagrammatic Representation

10. Types of Relation

11. One to One  One entity from entity set A can be associated with at most one entity of entity set B and vice versa diagram table

12. One to Many One entity from entity set A can be associated with more than one entities of entity set B however an entity from entity set B, can be associated with at most one entity. diagram table

13. Many to One More than one entities from entity set A can be associated with at most one entity of entity set B, however an entity from entity set B can be associated with more than one entity from entity set A. diagram table

14. Many to Many diagram One entity from A can be associated with more than one entity from B and vice versa.

15. Graphical representation Here is the graphical represenation of all relations: Table - A Table - B One to One Table - A Table - B One to Many Table - A Table - B Many to One Table - A Table - B Many to Many

16. Thank you