有关系模式:S学号,姓名,班级,课程号,课程名,成绩),为了使分解后的关系均达到3N

题型:单项选择题

问题:

有关系模式:S学号,姓名,班级,课程号,课程名,成绩),为了使分解后的关系均达到3NF,则至少需要将S分解成()

A.2个表

B.3个表

C.4个表

D.5个表

考点:02120数据库及其应用02120数据库及其应用题库
题型:单项选择题

根据短文内容判断正 (R)  误 (W)。

     The children often play football in the garden and sometimes break (打破) Mr. Black's windows. One

afternoon Mr. Black is at home and reads a book. In a minute he closes his eyes and goes to sleep. At that

time a little boy knocks at the door. Mr. Black opens the door and asks, "Do you break my window again (再

一次)?"

     "Oh, no" says the boy; "Your window is open this time and our football is in your room. May I get it

please?"

( )1. The children often play football in the park.    

( )2. Sometimes the children break Mrs. Black's windows.

( )3. Mr. Black watches TV one afternoon.              

( )4. The children's football is in Mr. Black's room.  

( )5. The children break Mr. Black's window again.     

题型:单项选择题

我国原始社会结束的时间是 [ ]

A.约公元前3000年

B.约公元前2500年

C.约公元前2070年

D.约公元前1100年

题型:单项选择题

油品的分子量随石油馏分的比重增加而()。

A、增大

B、减小

C、不变

题型:单项选择题

被誉为"方书之祖"的医著是()

A.《黄帝内经》

B.《伤寒杂病论》

C.《外台秘要》

D.《成方便读》

E.《医学源流论》

题型:单项选择题

某饮料广告画面中,沙漠中的狮身人面兽喝饮料。这是一种()

A.比喻式广告

B.印象式广告

C.音乐式广告

D.名人推荐式广告

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