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Chapter 7
Database Design and E-R Model
- Design Process
- Modeling
- Constraints
- E-R Diagram
- Design Issues
- Weak Entity Sets
- Extended E-R Features
- Design of the Bank Database
- Reduction to Relation Schemas
- Database Design
- UML
Overview of the Design Process
设计过程概览
two sequential phases
用户需求分析：数据库应该存哪些数据、哪些操作如插入删除更新检索
设计数据库纲要：
- 根据three-level of data abstract
- 纲要设计conceptual design
- 逻辑设计 logical design 逻辑层 视图层 logical level view level
- 物理设计 physical design 物理层 physical level
Entity - Relationship Model
实体-联系模型