问题
单项选择题
将E-R图转换到关系模式时，实体与联系都可以表示成( )。
A．属性
B．关系
C．键
D．域
答案
参考答案：B
解析：数据库逻辑设计的主要工作是将E-R图转换成指定RDBMS中的关系模式。首先，从E-R图到关系模式的 转换是比较直接的，实体与联系都可以表示成关系，E-R图中属性也可以转换成关系的属性。实体集也可以转换成关系。
搜题请搜索小程序“爱下问搜题”
将E-R图转换到关系模式时，实体与联系都可以表示成( )。
A．属性
B．关系
C．键
D．域
参考答案：B
解析：数据库逻辑设计的主要工作是将E-R图转换成指定RDBMS中的关系模式。首先，从E-R图到关系模式的 转换是比较直接的，实体与联系都可以表示成关系，E-R图中属性也可以转换成关系的属性。实体集也可以转换成关系。
Dear Li Tao, I am an American schoolgirl. My name is Alice Green. I am thirteen. There are five people in my family—my brothers, my parents and I. My brothers and I are all students and at the same school. We go to school from Monday to Friday. We don’t have any classes on Sundays or Saturdays. My father and mother are teachers. They say, China is great, and Chinese people are friendly(友好), I want to travel(旅行) in China. I think it is very interesting(有趣), isn’t it? I like reading. Now I am reading a book of Chinese stories. They are very interesting. My brothers and I like playing soccer(足球) and basketball. What do you like? Let’s be(成为) friends. Please write to me soon(快点). Alice Green Information Card
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