Enhanced Entity relationship Model

Chương 3 của bài giảng Hệ quản trị cơ sở dữ liệu giới thiệu về mô hình thực thể kết hợp mở rộng. Sau khi học xong chương này, người học có thể hiểu được: Khái niệm về mô hình EER; biết về Subclasses, Superclasses, và Inheritance; nắm bắt được các tiến trình tổng quát hóa và chuyên biệt hóa;... Mời các bạn cùng tham khảo.

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In this chapter, we describing features that have been proposed for semantic data models, and show how the ER model can be enhanced to include these concepts, leading to the Enhanced ER (EER) model.

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Chapter 4 (Part II) - Enhanced Entity-Relationship and UML modeling include contens as: Fundamental principle of modeling, basic process of modeling, add constraints - structural/ semantic,...

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Chapter 7 discusses how to design a relational database schema based on a conceptual schema design. This chapter presented a high-level view of the database design process, and in this chapter we focus on the logical database design or data model mapping step of database design. We present the procedures to create a relational schema from an Entity-Relationship (ER) or an Enhanced ER (EER) schema.

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Collection of similar entities or concepts into a higher level concept. EMPLOYEE class collects all employees into one class A class has properties called “class properties”. EMPLOYEE class has class properties - e.g., average salary, total number of employees. Each member has values for own properties (e.g. name, address, salary): called member properties.

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