ER model--Database Modeling The ER data mode was developed to facilitate database design by allowing specification of an enterprise schema that represents the overall logical structure of a database. The ER model is very useful in mapping the meanings and interactions of real-world enterprises onto a conceptual schema. Because of this usefulness,many database-design tools draw on concepts from the ER model. The ER data model employs three basic concepts: entity sets, relationship sets, attributes. The ER model also has an associated diagrammatic representation,the ER diagram,which can express the overall logical structure of a database graphically. Database System Concepts 7.7 @Silberschatz,Korth and SudarshanDatabase System Concepts 7.7 ©Silberschatz, Korth and Sudarshan ER model -- Database Modeling The ER data mode was developed to facilitate database design by allowing specification of an enterprise schema that represents the overall logical structure of a database. The ER model is very useful in mapping the meanings and interactions of real-world enterprises onto a conceptual schema. Because of this usefulness, many database-design tools draw on concepts from the ER model. The ER data model employs three basic concepts: entity sets, relationship sets, attributes. The ER model also has an associated diagrammatic representation, the ER diagram, which can express the overall logical structure of a database graphically