Question

What is an 'ER Diagram' (Entity-Relationship Diagram) used for in database design?

Q: Answer-What is an 'ER Diagram' (Entity-Relationship Diagram) used for in database design?

An ER diagram is a conceptual data model showing Entities tables e.g., Customer, Account, Branch, Attributes columns e.g., CustomerID, Name, and Relationships e.g., Customer HAS Account cardinality one-to-many. Cardinalities 11, 1N, MN. ER diagrams are created during the database design phase before actual table creation, serving as a blueprint for the relational schema. They are converted to physical schema during implementation.