【简答题】【消耗次数：1】
若关系模式R∈1NF，且每一个非主属性完全函数依赖于码，则称R∈[填空]。
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相关题目
【简答题】
关系模式R∈1NF，若每一个决定因素都包含码，则称R∈[填空]。
【单选题】
有关系模式R（U,F）∈1NF，若R中任意的非平凡的函数依赖X→Y，X中均包含码，则关系模式R的规范化程度至少为( )。
①
A．2NF
②
B．3NF
③
C．4NF
④
D．BCNF
【简答题】
有关系模式R(U,F)∈1NF，U=（A,B,C），若(A,B)→C，B→C，则该关系模式的规范化程度为[填空1]NF。
【简答题】
2NF是在1NF的基础上消除非主属性对码的[填空1]。
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I really do not know whether we can succeed, so do
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①
too much of us
②
us too much
③
of us too much
④
us of too much
【单选题】
Frank almost never received any education, ____?
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would he
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did he
③
didn’t he
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wouldn’t he
【单选题】
The teeth are ____, but they look very natural.
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false
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correct
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fake
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unnatural
【单选题】
You should know better than ____ your little sister at
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to leave
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leaving
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to have left
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left
【单选题】
There _____ a basketball match between Class One and Class Three this afternoon.
①
is going to be
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will have
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are going to be
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is going to have
【单选题】
A well written composition ____ good choice of words and clear organization among other things.
①
calls for
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calls on
③
calls up
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calls off
【单选题】
A large part of a person’s memory is ____ words and combination of words.
①
by means of
②
in terms of
③
in connection with
④
by way of
【单选题】
Outside my office window there is a fire ____ on the right.
①
escape
②
ladder
③
steps
④
stairs
【单选题】
____ in the past, at the moment it is a favorite choice for wedding gown.
①
Unpopular has as white been
②
White has been as unpopular
③
Unpopular has been as white
④
Unpopular as white has been