2012年计算机二级Access辅导笔记之创建Access数据库
第三章建树Access 数据库 3.1设计 数据库 3.2建树 数据库 的体例 3.3习题 3.1 关系 数据库 设计体例 关系 数据库 中,数据表是最根基的对象,表的 口角,直接关系到 数据库 的效率以及对 数据库 管 理和维护,是以,起头成立 数据库 之前,用户须 先对 数据库 中的
3.1设计数据库
3.2建树数据库的体例
3.3习题
3.1 关系数据库设计体例关系数据库中,数据表是最根基的对象,表的
口角,直接关系到数据库的效率以及对数据库管
理和维护,是以,起头成立数据库之前,用户须
先对数据库中的数据表进行细心的剖析和设计.
好比那些数据存放在一张表中,每个字段的名,
字段属性的设计,一个数据库中包含几张表,与
表之间的联系等
数据库表的设计体例
学分
课程名称
课程号
课程
班级
姓名
学号
学生
实体属性
实体
实例:学生选课系统
实体之间联系:多对多
初步设计关系表
85
4
多媒体
2145
计用05(3)
王五
055048011
80
4
数据库手艺
2304
计用05(3)
王五
055048011
76
4
多媒体
2145
计用05(2)
张三
055047006
85
4
数据库手艺
2304
计用05(2)
张三
055047006
成就
学分
课程名称
课程编号
班级
姓名
学号
表3-1
计用05(3)
王五
055048011
计用05(2)
张三
055047006
班级
姓名
学号
4
多媒体
2145
4
数据库手艺
2304
学分
课程名称
课程编号
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