Its all about E-R diagram. Very clear discuss all about information entity relationship.

1. Er-Model Discussion
• Ashiqur Rahaman Anik : 181-15-11012
• Mehedi Hasan: 181-15-10826
• Khadija Akter: 181-15-10924
• Nusrat Jahan Nisha: 181-15-11342

2. Introductionto ER Diagram
An Entity–relationship model (ER model) describes the structure
of a database with the help of a diagram, which is known as
Entity Relationship Diagram (ER Diagram).
An ER model is a design or blueprint of a database that can later
be implemented as a database. The main components of E-R
model are: entity set and relationship set.

3. Whatis anEntityRelationshipDiagram(ERDiagram)?
1. An ER diagram shows the relationship among entity sets.
2. An entity set is a group of similar entities and these entities
can have attributes.
3. ER diagram shows the complete logical structure of a
database.

4. A simple ER Diagram

5. Symbol of E-R Diagram
• Strong entity
• Weak entity
• Associative entity
Entity, Entity Type, Entity Set:

6. Symbol of E-R Diagram
Attributes:
• Key Attribute
• Composite Attribute
• Multivalued Attribute
• Derived Attribute

7. Symbol of E-R Diagram
Degree of a relationship set:
• Unary Relationship
• Binary Relationship
• n-ary Relationship

8. Keys of Er-Diagram
Types of keys in DB:
1.Primary key
2.Candidate key
3.Alternate key
4.super key
5.Foreign key

9. Keys of Er-Diagram

10. Keys of Er-Diagram

11. Example of Er-Diagram