Sunday, February 17, 2019

ER diagram

What is an ER diagram?

An Entity Relationship (ER) Diagram is a type of flowchart that illustrates how “entities” such as people, objects or concepts relate to each other within a system. ER Diagrams are most often used to design or debug relational databases in the fields of software engineering, business information systems, education and research. Also known as ERDs or ER Models, they use a defined set of symbols such as rectangles, diamonds, ovals and connecting lines to depict the interconnectedness of entities, relationships and their attributes. They mirror grammatical structure, with entities as nouns and relationships as verbs.

Uses of entity relationship diagrams

  • Database design
  • Database troubleshooting

The components and features of an ER diagram

  • Entity
  • Relationship
  • Attribute
  • Cardinality

ERD symbols and notations

 Referance: image :- https://www.smartdraw.com/entity-relationship-diagram/
                     https://stackoverflow.com/questions/1154382/anyone-have-an-erd-symbols-quick-reference 
 More Informations : https://www.lucidchart.com/pages/er-diagrams?a=0

No comments:

Post a Comment

React React  is a JavaScript library for building user interfaces created by Facebook. It is maintained by Facebook and a community of...