Accounts and Finance

"ER model stands for an Entity-Relationship model. It is a high-level data model and is used to define the data elements and relationship for a specified system. It develops a conceptual design for the database. It also develops a very simple and easy to design view of data.

In ER modeling, the database structure is portrayed as a diagram called an entity-relationship diagram.

Entity Relationship Diagram i.e. ERD, ER Diagram or ER model, is an structural diagram type for use in database design. It contains different symbols and connectors that visualize two important information i.e. :

i) the major entities within the system scope, and 

ii) the inter-relationships among these entities.

Drawing ER Diagram:

1. Make sure that the purpose of drawing the ERD is clear. 

2. Make sure that the scope to model is clear as it prevents from including redundant entities and relationships in the design.

3. Draw the major entities involved in the scope.

4. Define the properties of entities by adding columns.

5. Review the ERD carefully and check if the entities and columns are enough to store the data of the system.

6. Consider the relationships between all entities and relate them with proper cardinality.

7. Apply the technique of database normalization to re-structure the entities in a way that can reduce data redundancy and improve data integrity."