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1、数据库原理与应用A卷答案DAAADABCCDABDCBBADBC、1）外模式-模式模式-内模式2）选择投影连接3） 一对一一对多多对多4）级联删除相关字段5) 1NF1.1）人工管理阶段：数据不保存、没有专门的数据管理软件，程序和数据紧耦合2）文件管理阶段：出现操作系统，数据以文件方式保存，数据冗余大3）数据库系统阶段：出现专门的数据库管理系统，数据以结构化保存，数据独立性好2.数据库参照完整性是指两个相互联系的数据表之间通过外键建立联系，相互联系的数据之间要保证一致，数据库参照完整性是保证数据库数据正确可信的一个重要的约束机制3.ACCESS数据库中主要有表、查询、窗体、报表、数据访问页和模
2、块等对象表：保存数据查询：按要求得到指定数据窗体：提供用户和 ACCESS统间的程序界面报表：提供以可打印显示数据的方式页：将数据以网页的形式显示模块：提供以编程方式使用ACCESS4.数据定义语言： create、alter数据操纵语言： select、insert、delete、update数据控制语言：grant、revoke 四、select学号，姓名課程名，成绩From stude nts,courseWhere stude nt.学号=course.学号2)select 学号，姓名From stude ntsWhere 所在系=(select 所在系from student whe
3、re 姓名=孙小丽)3) select 姓名,avg(成绩),count(*)Where stude nt.学号=course.学号Order by avg(成绩)desc4) delete from courseWhere 学号=(select 学号 from students where姓名=陈有朋)五、(1)A1A2abbacaaddaeabddbeb(2)A1A2A3abcade(3)A1A2babd(4)A1A2A3abc(5)A1A2A3A1A2A3abcbacabcbacadebdeadebdeWhe n you are old and grey and full of slee
4、p,And no ddi ng by the fire, take dow n this book,And slowly read, and dream of the soft lookYour eyes had once, and of their shadows deep;How many loved your mome nts of glad grace,And loved your beauty with love false or true,But one man loved the pilgrim soul in you,And loved the sorrows of your
5、cha nging face;And bending dow n beside the glow ing bars,Murmur, a little sadly, how love fledAnd paced upon the mountains overheadAnd hid his face amid a crowd of stars.The furthest dista nee in the worldIs not betwee n life and deathBut whe n I sta nd in front of youYet you dont know thatThe furt
6、hest dista nee in the worldIs not whe n I sta nd in front of youYet you cant see my loveBut whe n un doubtedly knowing the love from bothYet cannot be together.The furthest dista nee in the worldIs not being apart while being in loveBut whe n I pla inly cannot resist the year ningYet prete nding you have n ever bee n in my heart.The furthest dista nee in the worldIs not struggli ng aga inst the tidesBut using on es in differe nt heartTo dig an un crossable riverFor the one who loves you.
