《数据库系统概论》| 第七章数据库设计知识梳理

阳光穿透心脏的1/2处 2023-10-06 11:43 21阅读 0赞

> ## 数据库设计 ##

**目录**

7.1 数据库设计概述

7.2 需求分析

7.3 概念结构设计

1.E-R模型

2.E-R图

3. 概念结构设计

7.4 逻辑结构设计

7.4.1 E-R图向关系模型的转换

7.4.2 数据模型的优化

7.4.3 设计用户子模式

7.5 物理结构设计

7.6 数据库的实施和维护

7.7 小结

--------------------

###  ###

1、数据库设计可以分为哪几个阶段？ 各阶段的主要工作包括哪些？

需求分析：调查了解用户的需求；用数据流图和数据字典来分析表达用户需求（结构化分析方法），以数据流图和数据字典作为这个阶段的成果；

概念结构设计：(用结构化的分析方法）抽象数据并设计局部视图，建立分E-R图；集成局部视图，合成总E-R图，消除分E-R图中三类冲突；

逻辑结构设计：将概念结构模型转化为一般的数据模型；将转化来的数据模型向特定的DBMS支持的数据模型转化；对数据模型进行优化（规范化）；设计用户模式；

数据库物理设计：确定数据库的物理结构，包括：确定存储结构、索引聚簇存取方法的选择、设计数据库的存储路径、确定数据库的存放位置、确定系统的配置；评价物理结构，从多种方案中选择一种最优的方案；

数据库实施阶段：定义数据库结构；数据装载；编制和调试应用程序；数据库试运行，进行功能测试、性能测试；

数据库运行与维护：经常性的维护工作由DBA完成：数据库的转储和恢复；数据库的安全性和完整性，根据实际需要授予用户不同的权限和修改完整性约束条件；数据库性能监督、分析和改进；数据库的重组织和重构造。

2、 视图的集成。要消除三种冲突

3 、逻辑结构设计：E-R图如何向关系模型的转换的规则。

### 7.1 数据库设计概述 ###

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 1][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 2][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 3][]

### 7.2 需求分析 ###

*  调查了解用户的需求；
 *  用数据流图和数据字典来分析表达用户需求（结构化分析方法），以数据流图和数据字典作为这个阶段的成果；

### 7.3 概念结构设计 ###

*  (用结构化的分析方法）抽象数据并设计局部视图，建立分E-R图；
 *  集成局部视图，合成总E-R图，消除分E-R图中三类冲突；

#### 1.E-R模型 ####

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 4][]![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 5][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 6][]![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 7][]  
![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 8][]![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 9][]

#### 2.E-R图 ####

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 10][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 11][]

#### 3. 概念结构设计 ####

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 12][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 13][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 14][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 15][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 16][]![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 17][]![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 18][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 19][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 20][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 21][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 22][]

![20190113201737970.png][]

### 7.4 逻辑结构设计 ###

*  将概念结构模型转化为一般的数据模型；
 *  将转化来的数据模型向特定的DBMS支持的数据模型转化；
 *  对数据模型进行优化（规范化）；
 *  设计用户模式；

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 23][]

#### **7.4.1 E-R图向关系模型的转换**  ####

![20190113203310395.png][]![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 24][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 25][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 26][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 27][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 28][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 29][]![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTIzMDk2_size_16_color_FFFFFF_t_70 30][]

#### **7.4.2 数据模型的优化**  ####

#### **7.4.3 设计用户子模式** ####

### 7.5 物理结构设计 ###

*  确定数据库的物理结构，包括：
    
     *  确定存储结构、
     *  索引聚簇存取方法的选择、
     *  设计数据库的存储路径、
     *  确定数据库的存放位置、
     *  确定系统的配置；
 *  评价物理结构，从多种方案中选择一种最优的方案；

### 7.6 数据库的实施和维护 ###

*  定义数据库结构；
 *  数据装载；
 *  编制和调试应用程序；
 *  数据库试运行，进行功能测试、性能测试；

### 7.7 小结 ###

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