问题
单项选择题
在关系数据库设计中，设计关系模式是数据库设计中哪个阶段的任务
A．需求阶段
B．概念设计阶段
C．逻辑设计阶段
D．物理设计阶段
答案
参考答案：C
解析：解析：逻辑设计的目的是从概念模型导出特定的DBMS可以处理的数据库的逻辑结构(数据库的模式和外模式)。在关系数据库设计中，设计关系模式是在数据库的逻辑设计阶段。
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在关系数据库设计中，设计关系模式是数据库设计中哪个阶段的任务
A．需求阶段
B．概念设计阶段
C．逻辑设计阶段
D．物理设计阶段
参考答案：C
解析：解析：逻辑设计的目的是从概念模型导出特定的DBMS可以处理的数据库的逻辑结构(数据库的模式和外模式)。在关系数据库设计中，设计关系模式是在数据库的逻辑设计阶段。
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| It was her giggling (咯咯笑) that drewmy attention. Note taking really wasn't all that funny. Walking over to the offender (肇事者), I asked for the 1 . Frozen, she refused to give it to me. I waited, all attention in the classroom on the quiet 2 between a teacher and a student. When she finally 3 it over she whispered, "Okay, but I didn't draw it." It was a hand-drawn 4 of me, teeth blackened and the words "I'm stupid" coming out of my mouth. I managed to fold it up calmly. My mind, 5 , was working angrily as I struggled not to 6 . I figured I knew the two most likely students who drew the picture. It would do them some 7 to teach them a lesson, and maybe it was high time that I did it. Thankfully, I was able to keep myself 8 . When there were about six minutes remaining, I showed the class the picture. They were all silent as I told them how 9 this was for me. I told them there must be a reason 10 and now was their chance to write down anything they needed to tell me. Then I let them write silently while I was seated in the back of the classroom, with tears in my eyes. As I 11 the notes later, many of them said something like, "I've got nothing 12 you." or "I'm sorry you were hurt." Some kids said, "We're afraid of you." But two notes, from the girls who I 13 drew the picture, had a list of issues. I was too 14 , too strict… Reading those notes, I realized that over the course of this year, instead of 15 my students, I had begun commanding them to 16 . Where I thought I was driving them to success I was 17 driving them away. I had some apology to make. But the next day in the classroom, one boy and one girl each handed me a card. The one 18 by all the boys expressed sincere regret for the ugly joke. The one from the girls asked for 19 . This was a lesson for both the kids and me. Forgiveness does not change the past, but it does enlarge the 20 . | ||||
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