: The most detailed version, showing actual table structures, data types, and constraints for a specific database management system.
An is a visual report used to design and model relational databases by illustrating how different "entities" (like people, objects, or concepts) relate to one another within a system. Core Components of an ERD AZ erdЕ‘rЕ‘l
: They serve as high-level documentation of a system’s information architecture. Levels of Abstraction : The most detailed version, showing actual table
: Represented as ovals, these describe the specific characteristics of an entity (e.g., a Customer entity might have attributes like Name or Email ). Levels of Abstraction : Represented as ovals, these
: They provide a common visual language for stakeholders, business analysts, and engineers to discuss data requirements.
: A high-level view showing major entities and their relationships without technical details.
: Analysts use them to identify logic errors in existing database structures.